GUIDELINES for gastric cancer staging and treatment
Gastric cancer (GC), despite the declining incidence, is still the third cancer-related cause of death after lung and liver neo-plasms . Although surgery remains the mainstay of therapy, in recent years there have been relevant progresses in endosco-pic treatment of early forms and in neoadju-vant, adjuvant and palliative chemotherapy of advanced cancers. Furthermore, radiolo-gical and pathological protocols have been standardized. Thus, a multidisciplinary team is required for a correct management of patients, from preoperative staging to follow-up.
From an historical perspective, Italian sur-geons were among the first in the West to acknowledge the indications of Eastern Centers; owing to the high incidence of this tumor in their Countries, the Japanese sur-geons developed a surgical approach ba-sed on extended (D2) and superextended (D3) lymphadenectomy, while the interven-tion more frequently performed in Europe and in USA provided for a limited lymphadenectomy (D1). This gave rise to a scien-tific conflict, which rested on an impressive difference in long-term survival (overall, 5-year survival rate of a patient with GC was around 75% in Japan  and 25% in Europe ). In this context, a number of Ita-lian surgeons started in the 80’s concentra-ting their efforts on more meticulous and aggressive nodal clearance, and providing a contribution in the worldwide spreading of Japanese therapy and results.
The Italian Research Group for Gastric Cancer (GIRCG) is a multidisciplinary re-search group, officially founded in 2001, which includes clinicians with recognized expertise in GC diagnosis, care and resear-ch from over 25 specialized Centers in Italy. The aim of GIRCG is to obtain results si-milar to those reported by Eastern Centers in terms of recurrence rate and survival. It involves a variety of medical professio-nals, ranging from surgeons, pathologists, gastroenterologists, medical oncologists, radiologists, nutritionists and statisticians, who all practice within the modern con-cepts of a multidisciplinary approach. The main targets of the group are the standar-dization of surgical treatment and exten-ded lymphadenectomy, pathological as-sessment, clinical staging, and multimodal treatment of GC in Italy, surgical, endosco-pic, pathological and radiological training, as well as the conduction of clinical studies and translational research. A mean of three meetings per year are conducted to ensu-re a continuity of collaboration. In the last 10 years the GIRCG published 45 papers in indexed journals and an international book , organized 12 workshops and 1 post-u-niversitary masterclass, and finally the 10th International Gastric Cancer Congress in June 2013 in Verona. Several research stu-dies are still ongoing.
In September 2013, surgical guidelines for GC were issued by the GIRCG and the Italian Society of Surgery (SIC), at the end of 3-months, web-based and Delphi method-based Consensus Conference
- The final version included 9 statemen-ts (Staging, Endoscopic Treatment, Ne-oadiuvant Therapy, Extent of Gastric Re-section, Lymphadenectomy, Associated Resections, Palliative Therapy, Mini-inva-sive Surgery, Follow-up), which were ap-proved in plenary session during the 105th SIC National Congress, October 2013, in Turin. Starting from these statements, in the following months a Commission was established inside the GIRCG, with the aim to translate those results into comprehen-sive indications for clinical management, including radiological, endoscopic, surgical, pathological and oncological paths. The result is herein exposed under the title of “GIRCG guidelines for GC staging and tre-atment – 2015”, and should be re-evalua-ted in 3 years. The present guidelines have not already been published elsewhere, even in Italian language nor other forms. The present paper has been approved by the Scientific Committee of the GIRCG.
Diagnosis and Staging
Diagnosis of GC is usually done – and should in every case be confirmed – by upper gastrointestinal (GI) endoscopy. Ba-sic informations to be given by endoscopy are: location (upper, middle, lower third, esophago-gastric junction (EGJ), divided in Siewert type I, II or III), size, macrosco-pic appearance and actual complications (obstruction/bleeding). Biopsies from the tumor should always be taken, in order to confirm histology and to classify into potentially useful classifications (Lauren histotype, WHO, see later). Chromoendo-scopy and biopsies of the gastric mucosa far from the tumor may be useful, in order to exclude multifocal disease. The suspi-cion of Barrett’s oesophagus should be specified and eventually confirmed by se-parate biopsies.
The pretreatment staging of GC should include in all the cases a contrast-enhan-ced thoraco-abdominal Multidetector row Computed Tomography (MDCT) with 16 or more rows. The MDCT examination should be performed with a spiral technique, using a dedicated protocol optimized to detect serosal invasion and minimal peritoneal disease, and images should be analyzed by an experienced reader (see appendix 1). Endoscopic ultrasound (EUS) may improve diagnostic accuracy of T stage, particular-ly in discriminating T1a from T1b or T2, or in case of an inadequate CT examination; however it is not strictly necessary in ad-vanced forms, whereas it is formally indica-ted in the selection of patients for endosco-pic treatment. Staging laparoscopy is also not strictly required, but it is recommended in cases deemed to be at risk of peritone-al carcinomatosis not visible or doubtful at CT examination. Staging laparoscopy is required also in many randomized clinical trials of adjuvant and neoadjuvant therapy. The cytological examination of peritoneal lavage, although limited by a low sensitivity, is a useful completion of the final patholo-gic staging.
Endoscopic treatment of Early Gastric Cancer (EGC)
Due to the excellent prognosis of EGC, en-doscopic procedures have been increasin-gly adopted for the treatment of selected cases with low risk for nodal metastases, with the aim of avoiding greater-than-ne-cessary morbidity and mortality related to gastrectomy. The GIRCG recognizes the criteria for appropriate endoscopic the-rapy of EGC reported in the Gastric Can-cer Treatment Guidelines 2010, published by the Japanese Gastric Cancer Associa-tion (JGCA) : the absolute criteria for standard treatment (including both EMR, endoscopic mucosal resection and ESD, endoscopic submucosal dissection) are differentiated-type adenocarcinoma, no ulcerative findings (UL(-)), depth of inva-sion clinically diagnosed as T1a (mucosal stage) and diameter not greater than 2 cm; the expanded criteria, to be proposed as an investigational treatment (only ESD should be employed) are tumors clinically diagno-sed as T1a and (a) of differentiated-type, UL(-), but greater than 2 cm in diameter, or (b) of differentiated-type, UL(+), and not greater than 2 cm in diameter. The re-section is judged as curative when all of the following conditions are fulfilled: en-bloc resection, tumor size not greater than 2 cm, histology of intestinal-differentiated-type, pT1a, negative horizontal (lateral) margin (HM0), negative vertical margin (VM0), and no lympho-vascular invasion . It is reasonable to treat EGC that meet the above mentioned characteristics by endoscopic techniques (EMR or ESD) only in experien-ced, high volume centers. Extended crite-ria may be proposed only to patients who accept to undergo long-term endoscopic surveillance and/or to participate into in-vestigational programs. In centers with low volume of endoscopic advanced procedu-res, gastrectomy remains the gold stan-dard for treatment of EGC .
The indication to perioperative chemothe-rapy should be considered and discussed within a multidisciplinary team in every case of locally advanced GC. The randomized studies MAGIC  and FNCLCC  are the principal reference, in Europe, for integrated protocols: these studies have demonstra-ted a survival benefit for neoadjuvant and peri-operative treatment in GC staged >T1 and/or N+. In MAGIC trial, the 5-year OS ra-tes were 36% among those who received perioperative chemotherapy and 23% in the surgery group (hazard ratio (HR): 0.75; P = 0.009). In FNCLCC trial, the 5-year OS rate was 38% for patients in the perioperative chemotherapy group and 24% in the sur-gery only group (HR: 0.69; P = 0.02). The corresponding 5-year DFS rates were 34% and 19% (HR: 0.65; P = 0.003), respectively. Multidisciplinary evaluation must consider several data which are important in the choice of an individualized treatment plan: an accurate preoperative stage of GC is dif-ficult to achieve; the symptoms related to advanced tumors, obstructing or bleeding, may contraindicate neoadjuvant treatment; very limited data exist in the possibility to predict the response of a single neoplasm to neoadjuvant treatment; only response to treatment determines the survival advanta-ge. Serosal infiltrating tumors, cancers with bulky (enlarged, clearly metastatic) nodes or Bormann type 4 cancers are a com-mon indication for neoadjuvant treatment, mainly with the aim of increasing the R0 re-sectability rate [11-13]. At present, there are doubts about the response rate of signet ring cell tumors to neoadjuvant treatment, due to a presumed intrinsic chemo-resi-stance of these cancers. It is possible that these cancers necessitate a different inte-grated treatment pathway. The GIRCG sug-gests to consider a neoadjuvant treatment for GC T>3 and/or with metastatic nodes on preoperative work-up, because the fi-ve-year survival probability of T1/T2 no-de-negative cases largely overcomes 80% in GIRCG series . Selection of neoadju-vant treatments should take into conside-ration some elements that may determine collateral effects and related postoperative morbidity: patient’s age, for example, can be a parameter to decide the use of inten-sive regimens. There still remains to define the rate of postoperative morbidity directly related to neoadjuvant treatment and the most effective treatment between preope-rative and perioperative schema.
SURGICAL THERAPY Resection
Curative surgery is distinguished in stan-dard gastrectomy (total or subtotal gastric resection and D2 lymphadenectomy), mo-dified gastrectomy (the extent of gastric resection and/or lymphadenectomy is re-duced compared to standard surgery) and extended gastrectomy (gastric resection plus surgical removal of adjacent involved organs and/or D2 plus lymphadenectomy). A sufficient resection margin should be ensured when determining the resection line in gastrectomy with curative intent. A proximal margin of at least 3 cm is re-commended for T2 or deeper tumors with an expansive growth pattern and 5 cm is recommended for those with infil-trative growth pattern and diffuse Lauren histotype. When these rules cannot be re-spected, it is advisable to examine the proxi-mal resection margin by frozen section. For tumors invading the esophagus, a 5-cm margin is not necessarily required, but fro-zen section examination of the resection line is desirable to ensure an R0 resection. For T1 tumors, a gross resection margin of 2 cm should be obtained. When the tumor border is unclear, preoperative endoscopic marking by clips of the tumor border will be helpful for decision-making regarding the resection line. Distal gastrectomy should be preferred when an adequate proximal resection margin can be obtained for distal tumors. Pancreatic or spleen invasion by tumor requiring pancreaticosplenectomy necessitates total gastrectomy regardless of the tumor location. Total gastrectomy should be considered for tumors that are located along the greater curvature of the corpus (when there is not an adequate sur-gical margin) or the fundus.
After distal gastrectomy, Roux-en-Y recon-struction seems superior to Billroth I and Billroth II reconstructions in terms of fun-ctional outcomes and long-term endosco-pic results; however, no clear conclusions are available in literature, and the choice of the procedure could be based on surgeon’s experience [15, 16]. After total gastrectomy, Roux-en-Y reconstruction remains the ea-siest solution, with satisfactory functional results.
Splenectomy is generally associated with an increased risk of post-operative com-plications in GC surgery. Final survival analysis of a randomized controlled trial (JCOG0110), designed to evaluate the role of splenectomy in total gastrectomy for proximal GC which does not invade the greater curvature, demonstrated signifi-cant non-inferiority of spleen preservation
- Total gastrectomy with splenectomy should be recommended for tumors that are located along the greater curvature or when a macroscopic involvement of sta-tions 4sa or 10 is present.
Combined cholecystectomy for asympto-matic gallstone in GC surgery may be con-sidered in young patients; otherwise, it is no clear if cholecystectomy is indicated in pa-tients without gallstones; a recent GIRCG multicenter study showed no difference in medium-term outcome between patients receiving or not prophylactic cholecystec-tomy .
The role of total omentectomy is still que-stionable, particularly for serosa-negati-ve advanced GC. Removal of the greater omentum is usually integrated in the stan-dard gastrectomy for T3 or deeper tumors. For T1/T2 tumors, the omentum more than 3 cm away from the gastroepiploic arcade may be preserved.
When the posterior gastric wall serosa is infiltrated by the tumor, removal of the in-ner peritoneal surface of the bursa omen-talis may be performed in order to remove microscopic tumor deposits in the lesser sac. In T1/T2 tumors, bursectomy should be avoided in order to prevent injury to the pancreas and/or adjacent vessels. A small-scale RCT showed a trend toward improved survival after bursectomy for tumors in the middle or lower third and for pathologically serosa-positive tumors .
The GIRCG takes strictly into account the Guidelines of the JGCA for indications, surgical procedure and classification of lymphadenectomy . In particular, the fol-lowing points are emphasized: the standard treatment for potentially curative resection is the D2, even after neoadjuvant treat-ment. Only in carefully selected cases (hi-gh-risk patients, early tumors not treatable by endoscopic resections) more limited procedures should be considered (D1, D1 plus). Otherwise, it is strictly necessary to follow the correct procedure of lymphade-nectomy, with special reference, along with other perigastric nodes, to an accurate and complete removal of infra-pyloric (station 6), right paracardial (station 1), left gastric artery (station 7), celiac axis (station 9), he-patic artery (station 8a), splenic artery (sta-tion 11p/d) and hepatoduodenal ligament (12a) nodes. It is also emphasized that in Italy the preoperative diagnosis of early for-ms is often unreliable, and the incidence of Lauren diffuse histotype, which is associa-ted with a higher risk of lymph node meta-stases even in early forms, is high . The D2 plus, which involves the lymphadenec-tomy of posterior stations (8p, 12p/b, 13), station 14v, and the additional removal of para-aortic nodes (16a2, 16b1), may be ju-stified in patients at high risk of metastases at these stations (advanced tumors of the upper third, advanced tumors and diffuse histotype located in the distal two-thirds of the stomach). However, these procedures should be performed in Centers specialized with the D2, or in clinical trials . The lym-ph node mapping on the fresh specimen is advisable, in order to check the quality con-trol of lymphadenectomy, and potentially increases the number of examined nodes, thus allowing a more correct staging of the disease.
Minimally invasive resective surgery (MIS)
Laparoscopic gastric resection for GC is an option that should be considered in patients with EGC: this approach carries advantages in terms of reduction of posto-perative stay, postoperative pain and return to normal activities. However, the results of MIS in terms of quality of life and long term survival are still under evaluation [22, 23]. Preliminary data seem to indicate that laparoscopic surgery is feasible also for AGC, but solid data on the advantages and oncologic efficacy of this approach coming from randomized trials are lacking, and the presence of a serosal cancer should still be considered a contraindication to MIS. There are some limitations to a diffuse ap-plication of these data, which come mainly from eastern RCT, including patients with BMI generally lower than those of Western patients, with less comorbidities and with tumors with a different biological behavior ; there would also be a problem con-cerning the learning curve for this proce-dure, that requires a caseload difficult to be reached in a short time in regions with a low prevalence of GC; in most of the stu-dies coming from the East, a “laparosco-pically assisted” technique was used, and such results are not directly transferrable to a totally laparoscopic approach; finally, beyond disease stage it should be consi-dered that the available evidence concerns only subtotal resections: total gastrectomy includes some technical steps that are not standardized and which still make the pro-cedure uncommon.
EGC is a malignant epithelial neoplasia li-mited to the mucosa and/or submucosa
- From a macroscopic point of view, EGCs are divided into 3 main types accor-ding to their endoscopic appearance: type
1 (protruding), type 2 (superficial), type3 (excavated). Kodama’s classification should also be mentioned, as it could pro-vide additional prognostic implications .
Advanced carcinomas should be classified into 4 macroscopic types according to the criteria proposed by Borrmann: polypoid, fungating, ulcerated and infiltrative. The dif-fuse variant may affect most of the stoma-ch and is commonly called linitis plastica or leather bottle stomach. The most widely used histological classification, both for early and advanced cancers, is the Lauren classification , which classifies GC ac-cording to 4 different types: intestinal, dif-fuse (signet-ring cell carcinoma belong to this group), mixed and indeterminate. The WHO classification should be also used in pathological report.
EMR/ESD complete and appropriated pa-thological report should provide all the fol-lowing items, in order to be considered as diagnostic and clinically useful:
• Number of specimens examined (en bloc vs. piecemeal resection)
• Macroscopic size of the specimen (all three dimensions should be reported)
• Macroscopic and microscopic size of the lesion
• Macroscopic tumor type
• Lauren histotype
•WHO classification with histologic grade
• Depth of invasion
• Presence or absence of intra-tumoral ulcer
• Presence or absence of lymphovascular invasion
- Resection margins status (horizontal and vertical, with the measurement of the distance from the lesion)
- Curative resection (yes/no)
When endoscopic, macroscopic and histo-logical sizes of the lesion are discordant, the microscopic measure is considered the gold standard. The depth of invasion of the tumor into the submucosal layer must be measured from the deepest part of muscu-laris mucosae.
Surgical pathological report of AGC should be conceived according to the following check list:
- Type of gastrectomy and lymphade-nectomy
- Tumor location
- Macroscopic type of the tumor
- Maximum tumor size
- Macroscopic distance of the lesion from the proximal and distal cut ends
- Resection margins status
- Lauren histotype
- WHO classification with histologic grade
- Depth of infiltration
- Presence or absence of lymphova-scular invasion
- Total number of examined lymph no-des
- Total number of positive lymph nodes
- Topography of examined and positive lymph node stations (optional)
- Peritoneal cytology or metastatic le-sions (when performed)
- pTNM Classification (7th Edition)
- In addition, in EGC, Kodama’s Classi-fication should be also added to the pathological report.
In order to evaluate the histological response of the tumor to neoadiuvant therapy, the Becker classification  should be mentio-ned: grade 1, complete or subtotal regres-sion (<10% residual tumor per tumor bed; grade 1a is complete regression and grade 1b is subtotal regression); grade 2, partial tumor regression (10%–50% residual tu-mor per tumor bed); grade 3, minimal or no tumor regression (>50% residual tumor per tumor bed).
Adjuvant treatments and integrated therapies
Adjuvant therapy (chemotherapy, radiothe-rapy or chemo-radiotherapy) could be re-commended in patients surgically treated for GC at stage II-III, in R1 resection or in case of lymph node metastases. A large meta-analysis confirmed the benefit of a 5-FU based adjuvant treatment in stage II-III, showing a reduced 5-y mortality of 18% in the experimental group . In Asian po-pulations, an overall survival benefit from adjuvant chemotherapy was confirmed following D2 resection in the ACTS-GC trial evaluating adjuvant S-1; the 5-year survival rate was 71.7% in the chemotherapy group versus 61.1% in the surgery-only group (HR: 0.67) . The CLASSIC trial evaluated an adjuvant capecitabine–oxaliplatin dou-blet chemotherapy after D2 gastrectomy, and reported significantly improved ove-rall survival (5-year survival rate was 78% in chemotherapy group versus 69% in the observation group) and disease-free sur-vival (HR: 0.58) with a 5-year disease-free survival of 68% in the adjuvant chemothe-rapy group and 53% in the surgery alone group . However, it should be noted that the benefit of postoperative chemotherapy following a D1 or D0 lymph node dissection has not been documented in these trials.
Cytoreductive surgery (CRS) plus HIPEC
represents a multidisciplinary approach for a selected subgroup of GC patients with peritoneal carcinomatosis (PC) and for ad-vanced resectable cases at high risk of de-veloping PC. Given that curative treatment failure in Western countries is mainly due to peritoneal recurrence and that a meta-a-nalysis composed almost entirely of Asian studies suggests the benefit of HIPEC as an adjuvant treatment , a European study on a Caucasian population is clear-ly warranted. In the meantime, HIPEC can be performed in selected patients having limited peritoneal carcinomatosis index (PCI<6) and in selected patients with me-tachronous PC. In cases with positive pe-ritoneal cytology without a macroscopic peritoneal carcinomatosis and in adjuvant setting, HIPEC would be better carried out in the context of clinical trials.
Palliative treatment is addressed to pa-tients affected by symptoms related to GC such as bleeding and obstruction. The main modalities of palliation are sur-gical procedures (resection and bypass), endoscopic therapies (stenting), bleeding control procedures (endoscopic and/or an-giographic), chemotherapy, and analgesic cares. The choice of modality depends on a variety of factors, including symptoms, performance status, potential response to combined therapies and individual patient prognosis, and should be made on ca-se-by-case basis.
Palliative gastrojejunostomy is beneficial for gastric outlet obstruction caused by unresectable advanced distal cancer in terms of improvement of oral food intake, with acceptable morbidity and mortality. However, its indication for patients with poor performance status is less clear, and in many cases endoscopic palliation is ef-fective as well. Reduction surgery includes gastrectomy made in a metastatic dise-ase to reduce the tumour volume and its related symptoms. This approach remains controversial. Recent results of REGATTA trial, conducted in Asian patients, did not show any survival benefit of gastrectomy followed by chemotherapy compared with chemotherapy alone in advanced GC with a single non-curable factor with an overall 2-year survival of 31.7% for patients trea-ted with chemotherapy alone vs. 25.1% for those treated with gastrectomy plus che-motherapy . Palliative gastrectomy as-sociated to liver resection and chemothe-rapy, when R0 resection can be obtained in patients fit for heavy surgery, has been reported to improve overall survival in se-lected groups of patients .
In medically fit patients with metastatic or locally advanced, not resectable GC, che-motherapy is recommended. Chemothe-rapy can provide palliation, improved sur-vival, and improved quality of life compared to best supportive care in patients with metastatic disease [35, 36]. Currently, pla-tinum-based and fluoro pyrimidine-based combinations are accepted as first-line drug regimens . Higher response ra-tes were observed in patients who recei-ved combination chemotherapy versus monotherapy. ECF (epirubicin, cisplatin, and 5-FU) and DCF (docetaxel, cisplatin, and 5-FU) regimens are recommended as first-line chemotherapy. However, DCF was associated with increased myelosup-pression and infectious complications. Oxaliplatin may represent an alternative to cisplatin with at least comparable acti-vity and a favourable global toxicity profi-le. Capecitabine is an orally administered fluoropyrimidine that is converted to fluo-rouracil intracellularly. Several studies have evaluated capecitabine, as a single agent or in combination regimens, in patients with GC. The REAL-2 study compared ca-pecitabine with fluorouracil and oxaliplatin with cisplatin . Results from this study suggest that capecitabine and oxaliplatin are as effective as fluorouracil and cispla-tin, respectively, in patients with previously untreated esophagogastric cancer with an HR: 0.86 for the capecitabine-fluorouracil comparison, and an HR: 0.92 for the oxa-liplatin-cisplatin comparison. Irinotecan as a single agent or in combination can be an alternative when platinum-based therapy cannot be delivered.
The ToGA trial  showed a significant improvement in overall survival with the addition of trastuzumab to a cisplatin-fluo-ropyrimidine doublet. However, the bene-fit of trastuzumab was limited to patients with a tumor score of IHC 3 + or IHC 2+ and FISH positive (HR: 0.74). Thus, for pa-tients with metastatic adenocarcinoma the assessment of HER2-neu overexpression using immunohistochemistry and fluore-scenze in situ hybridation is recommended. REGARD trial demonstrated a survival be-nefit for ramucirumab for patients with ad-vanced gastric adenocarcinoma progres-sing after first-line chemotherapy (HR:0.77). Based on the results of the REGARD trial, ramucirumab as a single agent is re-commended for advanced GC with disea-se progression, or after prior treatment by platinum-based or fluoro pyrimidine-based chemotherapy.
There is no evidence that routine follow-up after curative treatment of GC is associated with improved long term survival. However, routine follow-up should be offered to all patients for the following reasons: oncolo-gical (detection and management of cancer recurrence), gastroenterologic (endoscopic surveillance and management of postga-strectomy symptoms), research (collection of data on treatment toxicity, time to and site of recurrence, survival, and cost-bene-fit analyses), and pastoral (psychological and emotional support) [41, 42]. Follow-up should include lifetime monitoring of the nutritional sequelae of gastrectomy, inclu-ding, but not limited to, adequate vitamin B12, iron, and calcium replacement. Fol-low-up should be offered by members of the multidisciplinary team who managed the initial diagnosis, staging and treatment, including the gastroenterologist, the surge-on, the medical and radiation oncologists, and the general practitioner. Follow-up mo-dalities should be tailored to the individual patient, to the stage of their disease, and to the treatment options available in the event that recurrence is detected. Physical exa-mination rarely detects asymptomatic re-currence of GC, thus a program intended to detect asymptomatic recurrence should be based on cross-sectional imaging. Upper GI endoscopy may be used to detect local recurrence or metachronous primary GC in patients that have undergone a subto-tal gastrectomy. Routine screening for asymptomatic recurrence of GC may be discontinued after five years, as recurrence beyond that interval is infrequent .
The latest TNM classification defines jun-ctional carcinoma as oesophageal cancers, with the exception of upper third GC not infiltrating the Z line. The Siewert classification, even with the limitations caused by using only a topographical definition, often not unequivocal, remains of primary impor-tance in determining therapeutic strategies. In case of early junctional cancers, the en-bloc endoscopic resection (EMR-ESD) should be considered therapeutic in T1a, well-differentiated, non-ulcerated and ≤ 2 cm lesions. In early tumors outside from these criteria, endoscopic resection, even with free margins, plays only a role of sta-ging, for the high rate of lymph node me-tastases . Thus, T1 lesions that do not meet the above described criteria should be treated with surgery; the choice of re-section strategy is strictly dependent on the location with respect to the cardia: Siewert T1 tumors can be treated with abdo-minal approach if it is possible to ensure an oesophageal margin of at least 2 cm, otherwise a thoraco-abdominal approach is necessary.
In case of advanced junctional tumor, in recent years a multimodal therapy has gradually become the standard of care: for T≥2, regardless of N, Siewert I and II, as for squamous cell carcinoma of oesophagus, surgery should be preceded by neoadjuvant chemo-radiotherapy [45, 46] or chemothe-rapy . Siewert type III tumors follow the rules of advanced GC and should be trea-ted by neoadjuvant chemotherapy. Siewert I tumors are considered tumors of the distal oesophagus and the approach is the same. The best choice should be a trans-thoracic subtotal oesophagectomy, in order to allow an adequate lymphadenectomy. In Siewert III tumors the procedure of choice is total gastrectomy with D2 lymphadenectomy associated with trans-hiatal lower media-stinal lymphadenectomy or, in selected ca-ses, by left thoraco-phreno-laparotomy or right thoracotomy. A macroscopic proximal margin of at least 6 cm has been reported to increase the chance of surgical curabili-ty ; if this margin cannot be guarante-ed, analysis of margin by frozen section is recommended. Siewert II tumors have the chance of having in about one third of the cases both abdominal and thoracic lym-ph node involvement . For this reason, surgery cannot disregard a trans-thoracic way. The reconstruction by gastric conduit is preferable except in cases of major in-volvement of the stomach, where a total gastrectomy with intra-thoracic esopha-go-jejuno anastomosis should be provided.
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tu-mors of the gastrointestinal tract. They oc-cur with an incidence of at least 10 to 20 per million worldwide . GISTs typically occur in older adults, and the median pa-tient age varies between 60 and 65 years. Some series have shown a mild male pre-dominance. Over half of the GISTs occur in the stomach. Almost all GISTs express the KIT receptor tyrosine kinase, similar to the GI Cajal cells that regulate the GI auto-nomic nerve system and peristalsis, while approximately 85% to 90% of GISTs con-tain oncogenic KIT or PDGFRA mutations. A distinct subset of GISTs, characterized by wild type KIT/PDGFRA, defects of suc-cinate dehydrogenase (SDH) complex and peculiar prognostic features, tends to oc-cur at earlier ages, including infancy, and to prevail in females, sometimes arising in the context of Carney triad or Carney-Stra-takis syndrome . Most patients have symptoms or a palpable tumor at presen-tation, but about 25% are discovered inci-dentally. Tissue for pathological analysis can be obtained from tumor biopsies, done through endoscopic ultrasound guidan-ce, or through an ultrasound/CT-guided percutaneous approach or surgical speci-mens. The risk of peritoneal contamination in biopsies is minimal if the procedure is adequately carried out. Tumors at risk in this sense (e.g. cystic masses) should be biopsied only in high volume centers. Tu-mor tissue should be fixed in 4% buffered formalin; Bouin’s fixative should be avoided in order to avoid problems for mutational analysis. The diagnosis of GIST is based on a consistent morphology associated with immunohistochemical positivity for CD117 and/or DOG1 . In order to reduce the risk of false positives, it is advisable to carry out the immunoreaction for CD117 without unmasking of antigenic sites. About 5% of GISTs are CD117-negative. Any double ne-gativity of CD117 and DOG1 may be surro-gate for diagnostic purposes by the finding of a “canonical” mutation in exons 9, 11, 13 or 17 of KIT or in exons 12, 14 and 18 of PDGFRA.
Detected or suspected gastric GISTs that are 2 cm or more should be removed whe-reas smaller tumors can be excised or mo-nitored by endoscopy and/or imaging every 6-12 months . R0 of the tumor without rupturing the pseudocapsule is the goal of surgery, if possible with a macroscopic margin of 1-2 cm. Gastric or oesophageal GISTs should not be excised at endoscopy because R0 resection is difficult to achie-ve. Lymph-node dissection is generally not indicated because the prevalence of lym-ph-node metastases is about 1%. Small gastric GISTs can be excised by laparo-scopy by a skilled surgical team using an extraction bag.
Preoperative imatinib should be considered when an extended procedure is needed to remove the tumor. Tumor mutation analy-sis should be done to identify patients who do not benefit from preoperative imatinib. Five-year and 15-year recurrence-free survival rates for GISTs treated with sur-gery alone are estimated to be 70•5% and 59•9%, respectively. Only few tumors re-curred after the first 10 years of follow- up, suggesting that most patients (about 60%) with operable GIST are probably cured by surgery. Imatinib is the only treatment for GISTs that has been evaluated in the adju-vant setting, with results available from two randomized trials: adjuvant imatinib for at least 3 years has been recommended after surgery for high-risk patients. Patients with a small metastatic tumor burden have the longest progression-free survival times on imatinib treatment and, hypothetically, re-duction of tumor mass by surgery might prolong the time to drug resistance. Exci-sion of a single metastasis progressing during kinase inhibitor treatment could be considered.
The prognostic factors for GISTs are ana-tomic location, size and mitotic count per 5 mm2. It should be noted that the latter value is achieved with a different number of fields at high magnification depending on the microscope used. Therefore, it is ne-cessary to have a setup calibrated for the microscope adopted allowing for a count of 5 mm2 in place of the ambiguous 50 high-power fields (HPF) previously recom-mended in literature. The combination of these parameters defines the risk of relap-se. Tumor rupture in vivo (including during surgical procedures) represents another high-risk parameter, regardless of the in - trinsic prognostic features of a tumor .
The above reported guidelines represent the official GIRCG position in clinical mana-gement of GC, comprehensively covering the course of the disease, from diagnosis to follow up. They can be a useful tool to address physicians in managing patients with GC. According to the principles set out in these statements, physicians com-ply with the best, internationally accepted, actual standard of care.
Conflict of Interest
The authors declare that they have no con-flict of interest.
GUIDELINES for gastric cancer staging and treatment - Allegato