Gastric adenocarcinoma with para-aortic lymph node metastasis: a borderline resectable cancer?

Surgery Matters: Progress in Surgical Management of Gastric Cancer

OPINION STATEMENT

The surgical treatment of gastric carcinoma has progressed significantly in the past few decades. A major milestone was the establishment of multimodal therapies for locally advanced tumours. Improvements in the technique of endoscopic resection have supplanted surgery in the early stages of many cases of gastric cancer. In cases in which an endoscopic resection is not possible, surgical limited resection procedures for the early stages of carcinoma are an equal alternative to gastrectomy in the field of oncology. Proximal gastrectomy is extensively discussed in this context. Whether proximal gastrectomy leads to a better quality of life and better nutritional well-being than total gastrectomy depends on the reconstruction chosen. The outcome cannot be conclusively assessed at present. For locally advanced stages, total or subtotal gastrectomy with D2 lymphadenectomy is now the global standard. A subtotal gastrectomy requires sufficiently long tumour-free proximal resection margins. Recent data indicate that proximal margins of at least 3 cm for tumours with an expansive growth pattern and at least 5 cm for those with an infiltrative growth pattern are sufficient. The most frequently performed reconstruction worldwide following gastrectomy is the Roux-en-Y reconstruction. However, there is evidence that pouch reconstruction is superior in terms of quality of life and nutritional well-being. Oncological gastric surgery is increasingly being performed laparoscopically. The safety and oncological equivalency were first demonstrated for early carcinomas and then for locally advanced tumours, by cohort studies and RCTs. Some studies suggest that laparoscopic procedures may be advantageous in early postoperative recovery. Robotic gastrectomy is also increasing in use. Preliminary results suggest that robotic gastrectomy may have added value in lymphadenectomy and in the early postoperative course. However, further studies are needed to substantiate these results. There is an ongoing debate about the best treatment option for gastric cancer with oligometastatic disease. Preliminary results indicate that certain patient groups could benefit from resection of the primary tumour and metastases following chemotherapy. However, the exact conditions in which patients may benefit have yet to be confirmed by ongoing trials.

International Retrospective Cohort Study of Conversion Therapy for Stage IV Gastric Cancer 1 (CONVO-GC-1)

Aim

Much attention has been paid to conversion therapy for stage IV gastric cancer, however, its operative comorbidities and survival benefit have not yet been clarified. CONVO-GC-1, an international retrospective cohort study, was designed to investigate the role of conversion surgery in Japan, Korea, and China.

Methods

The rate of operative complications was the primary endpoint and the overall survival (OS), according to the four-category criteria previously published (Gastric Cancer:19; 2016), was analyzed as the secondary endpoint.

Results

A total of 1206 patients underwent surgery after chemotherapy with curative intent. Operative complications were observed in 290 (24.0%) patients in all grades, including pancreatic fistula and surgical site infection. The median survival time (MST) of all resected patients was 36.7 mo (M) and those of R0, R1, and R2 resection were 56.6 M, 25.8 M, and 21.7 M, respectively. Moreover, the MST of R0 patients were 47.8 M, 116.7 M, 44.8 M in categories 1, 2, and 3, respectively, and not reached in category 4. Interestingly, the MST of P1 patients was as favorable as that of P0CY1 patients if R0 resection was achieved. The MST of patients with liver metastasis was also favorable regardless of the number of lesions, and the MST of patients with para-aortic lymph node (LN) No 16a1/b2 metastasis was not inferior to that of patients with para-aortic LN No 16a2/b1 metastasis.

Conclusion

Conversion therapy for stage IV gastric cancer is safe and could be a new therapeutic strategy to improve the survival of patients, especially those with R0 resection.

The Clinicopathological Characteristics and Prognoses of dMMR Gastric Adenocarcinoma Patients

Background

Few studies on the clinicopathological features and prognosis of DNA mismatch repair deficiency (dMMR) gastric cancer (GC) have been reported, and no clear conclusions have been drawn about the factors affecting the prognosis of dMMR GC. The aim of this study was to explore the clinicopathological characteristics and prognoses of dMMR GC patients.

Methods

From May 2011 to November 2020, GC patients who underwent surgery with dMMR confirmed by immunohistochemistry (IHC) at the Affiliated Cancer Hospital of Shanxi Medical University were selected. The patients' clinical and pathological data were collected. The recurrence-free survival (RFS) and overall survival (OS) rates of the patients were determined through follow-up. SPSS 26.0 was used to analyze the patients' clinicopathological features and prognoses.

Results

A total of 162 dMMR GC patients met the inclusion criteria, and the median age was 63.5 years (32–89 years). dMMR GC was more common in males (65% vs. 35%), and most of the cases were stage II (the prevalence of stage I was 22%, that of stage II was 43%, that of stage III was 30%, and that of stage IV was 5%). Most of the lesions were located in the antrum (49%), followed by the cardia (25%). PMS2 and MLH1 (57%) deficiency was most common. Kaplan–Meier analysis showed that factors related to OS were family history (P = 0.048), number of lymph node (LN) metastases (P < 0.001), vascular tumor thrombus (P < 0.001), HER2 expression status (P = 0.025), and clinical stage (P < 0.001). The factors related to RFS included vascular tumor thrombus (P < 0.001), number of LN metastases (P < 0.001), and clinical stage (P < 0.001).

Conclusion

In this study, dMMR GC was more common in men, and the median age was 63.5 years. Most of the lesions were in the antrum and showed the combined deletion of MLH1 and PMS2. dMMR GC patients tended to be early stage, and the prognosis of those with early-stage GC was better. dMMR GC patients with vascular tumor thrombus or >6 LN metastases had a high recurrence rate and poor survival outcome.

Successful laparoscopic conversion surgery for gastric cancer with para-aortic lymph node metastasis after third-line chemotherapy: a case report

We herein reported a case of advanced gastric cancer (GC) with para-aortic lymph node (PALN) metastases who successful achieved downstaging following systemic chemotherapy and underwent curative laparoscopic conversion surgery. A 74-year-old male patient diagnosed with advanced GC and PALN metastases [cT4N3M1(LYM), stage IVA] was administered chemotherapy and immunotherapy for 28 months. After 27 courses of nivolumab as third-line chemotherapy, PALN enlargement was resolved, for which conversion surgery was planned. Subsequently, laparoscopic distal D2 gastrectomy with sampling para-aortic lymphadenectomy was performed, after which a pathological diagnosis of type V moderately differentiated tubular adenocarcinoma with mucinous adenocarcinoma, stage ypT3 (SS), ly1c, and v0, was established. The pathological proximal and distal tumor margins were negative. One lymph node metastasis was observed (No. 6; 1/25). The sampled lymph nodes were negative (No. 16a1: 0/2). The therapeutic effect was categorized as Grade 1a. The postoperative course was uneventful, with the patient receiving nivolumab to control for potential PALN metastases. Postoperatively, no recurrence was observed over 11 months. Laparoscopic conversion gastrectomy was successfully performed in a patient with advanced GC that was originally unresectable, suggesting that minimally invasive surgery may be a good option for originally unresectable advanced GC that becomes resectable.

Favorable Outcomes of Neoadjuvant Chemotherapy and Limited Para-Aortic Lymph Node Dissection for Advanced Gastric Cancer with Para-aortic Lymph Node Metastasis

BACKGROUND

Although para-aortic lymph node (PALN) metastasis from gastric cancer is a non-curative lesion, gastrectomy with complete PALN dissection (PAND) following neoadjuvant chemotherapy (NAC) is a tentative standard treatment in Japan, based on the results of a small-scale phase II clinical trial. However, whether complete PAND (C-PAND) is always necessary for such diseases is open to debate.

METHODS

Patients who received NAC followed by R0 gastrectomy for gastric cancer with clinical PALN metastasis at the Cancer Institute Hospital in Tokyo from 2005 to 2017 were reviewed in the present study. We assessed surgical findings and long-term outcomes.

RESULTS

In total, 44 patients receiving gastrectomy with C-PAND (n = 22) or limited PAND (L-PAND; n = 22) were included. Operation time was significantly longer in the C-PAND than in the L-PAND groups (363 min vs. 271 min, P = 0.037). There was no difference between the two groups in the ypStage classification and pattern of recurrence. The 5-year overall survival (OS) and relapse-free survival (RFS) curves were higher in the L-PAND group than the C-PAND group, without reaching a significant difference. The 5-year OS (42.9% vs. 75.7%, p = 0.017) and RFS (14.3% vs. 48.6%, p = 0.002) were significantly worse in the group of three or more, than in the group of less than three pathological PALN metastasis, whereas increasing numbers of harvested PALN were not associated with improved survival.

CONCLUSIONS

Curative gastrectomy with L-PAND following NAC for gastric cancer involving PALN may be an alternative treatment to C-PAND.

Curative para-Aortic lymph node dissection Via INfra-mesocolonic approach in laparoscopic Gastrectomy (CAVING approach)

PURPOSE

Para-aortic lymph node (PAN) metastasis for gastric cancer is considered a distant lymph node metastasis. Meanwhile, multidisciplinary treatments have improved survival of patients with PAN metastases. We developed a novel technique of curative para-aortic lymph node dissection via infra-mesocolonic approach in laparoscopic gastrectomy (CAVING approach). This method minimizes the mobilization of the pancreas and the spleen and maximizes the view from the caudal side resembling cave exploration.

METHODS

After laparoscopic gastrectomy, PAN dissection is performed using the same ports setup. The retroperitoneum is widely exposed to ease anatomical cognition and for troubleshooting. The inferior vena cava, the left gonadal vein, the left renal vein, and the aorta are recognized under Gerota's fascia. The retroperitoneum is then divided into four sections. We perform PAN dissection in the order of 16blat, 16b1int, 16a2lat, and then 16a2int. Using the CAVING approach, the caudal side of the root of the superior mesenteric artery can then be dissected below the pancreas, and only the cranial side of the SMA root requires a suprapancreatic approach.

RESULTS

In three cases, preoperative chemotherapy and laparoscopic gastrectomy plus D2 with PAN dissection were performed for gastric cancer and esophagogastric junction cancer. The median operation totaled 484 min, 142 min for the PAN dissection. The median whole blood loss was 130 ml. The median harvested number of PAN was 25.

CONCLUSIONS

The minimal mobilization of pancreas and the wide surgical fields by CAVING approach may facilitate safe and reliable PAN dissection.

Trastuzumab-based palliative chemotherapy for HER2-positive gastric cancer: a single-center real-world data

Background

Since the results of the ToGA trial were published, trastuzumab-based chemotherapy has been used as the standard first-line treatment for HER2-positive recurrent or primary metastatic gastric cancer (RPMGC). However, the real-world data has been rarely reported. Therefore, we investigated the outcomes of trastuzumab-based chemotherapy in a single center.

Methods

This study analyzed the real-world data of 47 patients with HER2-positive RPMGC treated with trastuzumab-based chemotherapy in a single institution.

Results

With the median follow-up duration of 18.8 months in survivors, the median overall survival (OS) and progression-free survival were 12.8 and 6.9 months, respectively, and the overall response rate was 64%. Eastern Cooperative Oncology Group performance status 2 and massive amount of ascites were independent poor prognostic factors for OS, while surgical resection before or after chemotherapy was associated with favorable OS, in multivariate analysis. In addition, 5 patients who underwent conversion surgery after chemotherapy demonstrated an encouraging median OS of 30.8 months, all with R0 resection.

Conclusions

Trastuzumab-based chemotherapy in patients with HER2-positive RPMGC in the real world demonstrated outcomes almost comparable to those of the ToGA trial. Moreover, conversion surgery can be actively considered in fit patients with a favorable response after trastuzumab-based chemotherapy.

Significance of nodal dissection and nodal positivity in gastric cancer

Lymphadenectomy is a central component of surgery for gastric cancer. However, controversies over the optimal extent of lymphadenectomy in gastric cancer surgery have persisted for several decades. In Eastern countries where the incidence of gastric cancer is high, surgeons have performed extensive lymphadenectomy (D2 lymphadenectomy) with low morbidity and mortality, while most Western surgeons have advocated for more limited lymphadenectomies according to the results of Dutch trial and MRC trial. Initially, these trials had failed to show survival benefit of D2 procedure and instead, found pancreaticosplenectomy performed as part of the D2 procedure associated with high incidence of morbidity and mortality. Subsequently, superiority of D2 lymphadenectomy on survival was demonstrated based on updated results. Moreover, spleen and pancreas preserving D2 lymphadenectomy are being performed safely in Western countries. Today, there is an international consensus on performing D2 lymphadenectomy as the standard procedure for advanced gastric cancer and is widely accepted as the standard procedure for gastric cancer surgery. The significance of the extent of lymphadenectomy is intimately associated with the prognostic importance of nodal metastases as the most powerful indicator of recurrence and survival for patients after curative gastrectomy. Maruyama computer program could be used to estimate the risk of lymph node metastasis in each nodal station. The Maruyama Index could be used to assess the adequacy of lymphadenectomy in gastric cancer. Positive lymph node ratio is calculated as the ratio of positive lymph nodes to all harvested lymph nodes, which might be a more precise predictor of prognosis than the absolute number of positive lymph nodes. While D2 lymphadenectomy enables the accurate staging of the disease, reduces the incidence of locoregional recurrences and thus contribute to an improved overall survival; performing lymphadenectomy beyond D2 is unlikely to improve survival. Therapeutic D2+ lymphadenectomy for advanced gastric cancer requires further evaluations, especially for patients receiving neo-adjuvant or conversion treatments.

Optimization of perioperative approaches for advanced and late stages of gastric cancer: clinical proposal based on literature evidence, personal experience, and ongoing trials and research

BACKGROUND

The high incidence of gastric cancer (GC) and paradoxical high prevalence of advanced stage GC, amounting to around 2/3 at time of diagnosis, have urged doctors and researchers around the world not only to ameliorate the detection rate of GC at early stages but also to optimize the clinical management of GC at advanced stages.

CONTENT

We hereby recommend a more goal-oriented multimodality approach with objectives to increase survival rate and improve survival status. Based on precision and accurate clinical staging at diagnosis, we suggest that advanced stage GC (AGC) patients should be channeled into different treatment plans according to their disease status where they can be subjected to comprehensive measures involving chemo, radio, immunological, or target therapies depending on the pathophysiological behavior of their tumor. Patients assessed as potentially resectable cT4N + M0 can undergo neoadjuvant chemotherapy with intent of tumor downsizing and downgrading followed by surgery with intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC) to decrease the incidence of peritoneal dissemination due to surgical trauma and adjuvant chemotherapy and radiation in cases of bulky nodal metastasis. In cases with distal metastasis, conversion therapy is recommended with the possibility of surgery of curative intent in case of favorable response. The options of alternate treatment options such as trans-catheter arterial chemoembolization (TACE) for limited liver lesions or neoadjuvant intraperitoneal plus systemic chemotherapy (NIPS) for peritoneal carcinomatosis have to be negotiated. With surgery as the cornerstone for cancer treatment, there is acknowledgment of the significance of perioperative comprehensive approaches but there has not been some consensus guiding clinical application. Henceforth, in this review, based on past literature, current guidelines and ongoing clinical trials, we have shared a proposal of the current treatment modalities in practice for the advanced stages of gastric cancer.

CONCLUSION

Even though surgery is the golden standard of radical cancer treatment, clinical reality shows that without proper perioperative management, patients undergoing radical resections manifest high rates of recurrence and metastasis. Hence, in this review, we have outlined a clinical agenda to optimize the management of advanced stage GC with objective to improve survival outcome and quality of life of patients.

Role of D2 gastrectomy in gastric cancer with clinical para-aortic lymph node metastasis

BACKGROUND

Owing to the technical difficulty of pathological diagnosis, imaging is still the most commonly used method for clinical diagnosis of para-aortic lymph node metastasis (PALM) and evaluation of therapeutic effects in gastric cancer, which leads to inevitable false-positive findings in imaging. Patients with clinical PALM may have entirely different pathological stages (stage IV or not), which require completely different treatment strategies. There is no consensus on whether surgical intervention should be implemented for this group of patients. In particular, the value of D2 gastrectomy in a multidisciplinary treatment (MDT) approach for advanced gastric cancer with clinical PALM remains unknown.

AIM

To investigate the value of D2 gastrectomy in a MDT approach for gastric cancer patients with clinical PALM.

METHODS

In this real-world study, clinico-pathological data of all gastric cancer patients treated at the Cancer Hospital, Chinese Academy of Medical Sciences between 2011 and 2016 were reviewed to identify those with clinically enlarged PALM. All the clinico-pathological data were prospectively documented in the patient medical record. For all the gastric cancer patients with advanced stage disease, especially those with suspicious distant metastasis, the treatment methods were determined by a multidisciplinary team.

RESULTS

In total, 48 of 7077 primary gastric cancer patients were diagnosed as having clinical PALM without other distant metastases. All 48 patients received chemotherapy as the initial treatment. Complete or partial response was observed in 39.6% (19/48) of patients in overall and 52.1% (25/48) of patients in the primary tumor. Complete response of PALM was observed in 50.0% (24/48) of patients. After chemotherapy, 45.8% (22/48) of patients received D2 gastrectomy, and 12.5% (6/48) of patients received additional radiotherapy. The postoperative major complication rate and mortality were 27.3% (6/22) and 4.5% (1/22), respectively. The median overall survival and progression-free survival of all the patients were 18.9 and 12.1 mo, respectively. The median overall survival of patients who underwent surgical resection or not was 50.7 and 12.8 mo, respectively. The 3-year and 5-year survival rates were 56.8% and 47.3%, respectively, for patients who underwent D2 resection. Limited PALM and complete response of PALM after chemotherapy were identified as favorable factors for D2 gastrectomy.

CONCLUSION

For gastric cancer patients with radiologically suspicious PALM that responds well to chemotherapy, D2 gastrectomy could be a safe and effective treatment and should be adopted in a MDT approach for gastric cancer with clinical PALM.

Recent Advances in the Surgical Treatment of Advanced Gastric Cancer: A Review

Gastric cancer is a common malignancy with a poor prognosis, and surgical treatment remains the first-line approach to treatment to provide a cure. Despite advances in surgical techniques, radiotherapy, chemotherapy, and neoadjuvant therapy, gastric cancer remains the second leading cause of cancer death worldwide. Although the 5-year survival rate of early gastric cancer can reach >90%, due to the low early diagnosis rate, most patients present with advanced-stage gastric cancer. Therefore, there has been increasing interest in improving surgical treatment of advanced gastric cancer. Lymph node dissection is an important part of the surgical treatment of advanced gastric cancer due to the high incidence of lymph node metastasis. Although prospective studies have confirmed the safety and feasibility of laparoscopic surgery for early gastric cancer, the relevant treatment models of advanced gastric cancer still need to be further explored and validated. This review aims to provide an update on the recent advances in the surgical treatment of advanced gastric cancer.

Is there a role for treatment-oriented surgery in stage IV gastric cancer? A systematic review

To analyze the available evidence on the role of treatment-oriented surgery in stage IV gastric cancer (metastatic disease), a systematic literature search was undertaken using Medline, Embase, Cochrane, and Web-of-Science libraries. The search was not restricted to articles published within a given year range. Articles written in English language (or with abstracts written in English) were considered. All references in the chosen articles were further screened to find additional relevant publications. Both clinical series and literature reviews were included. Stage IV gastric cancer is classified into four subcategories: positive peritoneal cytology without clear macroscopic peritoneal involvement (surgery is usually performed in these cases); gross appearance peritoneal carcinomatosis [surgery, eventually with hyperthermic intraoperative peritoneal chemotherapy (HIPEC) may be considered in very selected cases with limited PCI]; nodal metastases outside the loco-regional nodes (surgery may not be denied for metastatic nodes in stations 13 and 16); and hematogenous metastases (surgery should be performed in selected cases with liver metastases suitable to R0 resection). The analysis incorporated the new biological classification of stage IV gastric cancer recently proposed by Japanese researchers (Yoshida et al. in Gastric Cancer 19:329-338. https://doi.org/10.1007/s10120-015-0575-z , 2015) into the four aforementioned subcategories to make the comparison of the issues discussed meaningful. The take home message from the existing literature is that treatment-oriented surgery may be performed in a significant proportion of patients with stage IV gastric cancer.

Para-aortic lymphadenectomy in surgery for gastric cancer: current indications and future perspectives

Involvement of para-aortic nodes (PAN) has been detected at pathological examination in 10-25% of locally advanced gastric cancer. Based on these data of nodal diffusion, the lymphadenectomy of para-aortic stations would be desirable in locally advanced gastric cancer. However, the debate on the oncological benefit of para-aortic nodes dissection is still not solved. A review of the literature was performed and papers reporting either the rate of para-aortic nodal metastases or the long-term survival outcomes after D2+ para-aortic nodes dissection (PAND) or D3 lymphadenectomy were descriptively reported. The literature survey yielded 14 studies. Most of the papers show the outcome of series of advanced gastric cancer treated with surgery alone, while starting from 2012, 3 articles report the outcomes of D2 + PAND or D3 lymphadenectomy after preoperative chemotherapy. The rate of PAN metastases ranges between 8.5 and 28% in surgical series. Survival outcomes largely improved in series of patients treated with multimodal approach compared to those of surgery alone. In patients with clinically detected para-aortic nodal metastases, preoperative chemotherapy followed by PAND is indicated. More data are needed to clarify the indication to prophylactic PAND in the era of multimodal treatment, anyway super-extended lymphadenectomies have to be performed by experienced surgeons in dedicated centres.

Clinical impact of molecular classifications in gastric cancer

Treatment options to gastric cancer (GC) have been changing in recent years from a standard to a tailored approach. Different individualized procedures can range from endoscopic resection, D2 with open or minimally invasive approach, to neo-adjuvant therapy followed by extended surgery. In more advanced stages, a combined approach with the inclusion of intraperitoneal chemo-hyperthermia (HIPEC) may represent a new advanced option. The inclusion of histological type according to Laurén classification in the flowchart of treatment could increase both accuracy and effectiveness of such tailored approach. New molecular classifications of GC have been introduced recently and translational clinical studies are ongoing. These classifications are expected to be included in multidisciplinary treatment of GC. In particular, in the group with microsatellite instability a less extended lymphadenectomy may be proposed. Also tailored neo-adjuvant treatment may be proposed according to molecular classifications. The group of patients with epithelial-to-mesenchymal transition shows very high propensity to peritoneal dissemination, as well as N-metastases, and may benefit from prophylactic HIPEC and extended lymphadenectomy when confirmed in prospective trials.

Is There Any Role for D3 Lymphadenectomy in Gastric Cancer?

Although D2 constitutes the level of lymph node dissection which most surgical associations endorse in their treatment guidelines for gastric cancer more extended D3 dissection has also been attempted to improve oncologic outcomes. Existing literature pertinent with the provisional therapeutic impact of D3 lymphadenectomy in advanced gastric cancer is studied in this mini review. Seven non-randomized comparisons, three randomized trials and five meta-analyses, almost exclusively of Asian origin, were identified and examined. D3 compared to D2 lymphadenectomy consistently and significantly proved to be associated with a “heavier” iatrogenic surgical trauma translated to more blood loss, prolonged operative time, higher relaparotomy rates and post-procedural surgical and non-surgical morbidity. Oddly mortality in most of these series did not reach statistical significance a fact probably attributed to Asian surgical expertise and/or methodologic drawbacks. All existing evidence and their meta-analyses, including a well-designed RCT from Japan (JCOG), failed to support a clear overall survival benefit linked to D3 dissection thus excluding the procedure from current treatment algorithms. The Italian GC research group, analyzing their database, proposed tumor histology, macroscopic type, size and location as selection criteria for D3 dissection provided surgical expertise is available. Recently, a phase II clinical trial from Japan reported a 3 -year survival rate of 59% in patients with clinically involved para-aortic nodes treated with neoadjuvant chemotherapy followed by D3 lymphadenectomy, rekindled the issue. Future multicenter randomized trials should test the extend and after effect of lymphadenectomy in gastric cancer combined with modern chemotherapeutic agents in multimodal treatments.

The long-term survival of stage IV gastric cancer patients with conversion therapy

PURPOSE

A retrospective study was performed to clarify the role of conversion therapy (surgery with a prospect of R0 resection performed in initially unresectable metastatic cancer that responded to the chemotherapy) in stage IV gastric cancer (GC).

PATIENTS AND METHODS

We treated 259 stage IV GC patients with systemic chemotherapy at Gifu and Hiroshima University Hospitals between 2001-2013. Of these, 84 patients who were subsequently treated by surgery were classified into four categories according to our previously published classification of stage IV GC, and short- and long-term outcomes were analyzed.

RESULTS

Surgery was performed in 84 patients, of which 7 were performed following the neoadjuvant chemotherapy, whereas the other 77 that excluded neoadjuvant chemotherapy cases were considered the conversion therapy. The postoperative mortality and morbidity were comparable with those reported clinical trials. The MSTs of the patients with/without surgery for each category were 28.3/5.8 months for category 1, 30.5/11.0 months for category 2, 31.0/18.5 months for category 3 and 24.7/10.0 months for category 4. The MST of the R0 resected patients (41.3 months) was far better than that of the R1-2 resected patients (21.2 months). The MSTs of the patients with R0/R1-2 resection were 56.2/16.3 months for category 2, 33.3/29.6 months for category 3 and 40.7/17.8 months for category 4.

CONCLUSION

There were long-term survivors who underwent conversion therapy for stage IV GC. Adequate selection of stage IV GC patients for conversion therapy may be an important role for the surgical oncologist in the new era.

Incidence and Prognostic Value of Metastases to "Posterior" and Para-aortic Lymph Nodes in Resectable Gastric Cancer

BACKGROUND

The purpose of this retrospective study was to evaluate the incidence and prognostic value of metastases to "posterior" (8p, 12b/p, 13) and para-aortic lymph nodes in a large cohort of Western patients submitted to D2 plus lymphadenectomy.

METHODS

Removal of "posterior" nodes was performed in 743 patients, and para-aortic lymphadenectomy in a subgroup of 390 patients. After lymph node mapping and retrieval on the fresh specimen, a median number of 41 total lymph nodes were analyzed. The median follow-up period was 37 months for the entire series and 68 months for survivors.

RESULTS

Of 743 included patients, 23 (3.1%) had metastases in station 8p, 12 (1.6%) in station 12b/p, and 19 (2.6%) in station 13. On the whole, 47 of 743 patients (6.3%) had positive "posterior" nodes. Para-aortic metastases were present in 42 of 390 patients (10.8%). Metastases to "posterior" stations were significantly related to depth of invasion, number of positive nodes, and surgical radicality. Distal tumors showed higher trend to metastasize to "posterior" nodes than upper third, whereas for para-aortic metastases it was the reverse. 5-year survival in patients with positivity to "posterior" nodes was 17%, with no significant difference according to 8p, 12b/p, and 13 stations; long-term outcome was overlapping to pN3b stage. 5-year survival in para-aortic positive cases was 11%, and a trend to better outcome was observed in proximal tumors.

CONCLUSIONS

Although metastases to "posterior" and para-aortic nodes are expression of an advanced nodal stage, not negligible survival rates are observed in subgroups of patients.

Application of conversion therapy in advanced gastric cancer

Patients with advanced gastric cancer (AGC) have short overall survival and poor prognosis. Current guidelines recommend palliative treatments. The success of conversion therapy in liver metastases of colorectal cancer gives an inspiration to AGC treatment. Some small sample studies indicated that conversion therapy provided AGC patients longer overall survival time compared to those who received palliative treatments. The application of conversion therapy in AGC is still lack of effective evidence of evidence-based medicine. The multidisciplinary team (MDT) mode is an important guarantee for the conversion therapy of AGC. The conversion therapy of AGC requires multi-disciplinary comprehensive treatment. This article makes a comprehensive discussion on the choice of cases, treatment plans and timing of treatment from the perspective of nonsurgical treatment, with an aim to provide a reference for clinical treatments.

Gastric cancer: Current status of lymph node dissection

D2 procedure has been accepted in Far East as the standard treatment for both early (EGC) and advanced gastric cancer (AGC) for many decades. Recently EGC has been successfully treated with endoscopy by endoscopic mucosal resection or endoscopic submucosal dissection, when restricted or extended Gotoda's criteria can be applied and D1+ surgery is offered only to patients not fitted for less invasive treatment. Furthermore, two randomised controlled trials (RCTs) have been demonstrating the non inferiority of minimally invasive technique as compared to standard open surgery for the treatment of early cases and recently the feasibility of adequate D1+ dissection has been demonstrated also for the robot assisted technique. In case of AGC the debate on the extent of nodal dissection has been open for many decades. While D2 gastrectomy was performed as the standard procedure in eastern countries, mostly based on observational and retrospective studies, in the west the Medical Research Council (MRC), Dutch and Italian RCTs have been conducted to show a survival benefit of D2 over D1 with evidence based medicine. Unfortunately both the MRC and the Dutch trials failed to show a survival benefit after the D2 procedure, mostly due to the significant increase of postoperative morbidity and mortality, which was referred to splenopancreatectomy. Only 15 years after the conclusion of its accrual, the Dutch trial could report a significant decrease of recurrence after D2 procedure. Recently the long term survival analysis of the Italian RCT could demonstrate a benefit for patients with positive nodes treated with D2 gastrectomy without splenopancreatectomy. As nowadays also in western countries D2 procedure can be done safely with pancreas preserving technique and without preventive splenectomy, it has been suggested in several national guidelines as the recommended procedure for patients with AGC.

Conversion therapy for unresectable gastric cancer

Unresectable gastric cancer cases are often diagnosed at a far advanced stage, which are hard to resect radically and suffer a poor prognosis. Therefore, palliative chemotherapy is recommended as the main treatment by the current clinical guidelines for gastric cancer. Fortunately, in recent years some clinical studies revealed that after treatment with chemotherapy, radiotherapy, targeted therapy, interventional therapy, hyperthermic intraperitoneal chemotherapy (HIPEC) and so on, and multidisciplinary assessment, many unresectable gastric cancer cases could be converted into resectable cases, which consequently prolongs their survival time and improves their quality of life significantly. In the present review, we summarize the status and progress of treatment for unresectable gastric cancer, as well as the strategy and case selection for conversion therapy.

Is conversion therapy possible in stage IV gastric cancer: the proposal of new biological categories of classification

Conversion therapy for gastric cancer (GC) has been the subject of much recent attention. It is defined as a surgical treatment aiming at an R0 resection after chemotherapy for tumors that were originally unresectable or marginally resectable for technical and/or oncological reasons. However, the indications for resection remain to be clarified. In the present review, we focus on the biology and heterogeneous characteristics of stage IV GC and propose new categories of classification. Stage IV GC patients can be divided based on the absence (categories 1 and 2) or presence (categories 3 and 4) of macroscopically detectable peritoneal dissemination, which has a different biological outcome compared to hematological metastasis. Category 1 is defined oncologically as stage IV but the metastasis is technically resectable. Category 2 includes a marginally resectable metastasis or patients for whom the operation would not necessarily be the best choice. Category 3 includes a potentially unresectable metastasis of peritoneal dissemination that is only macroscopically detectable. Category 4 includes noncurable metastasis with peritoneal and other organ metastasis. The indications for conversion therapy might include the patients from category 2, some patients from category 3 and a very small number of patients from category 4. The longer survival can be expected for patients corresponding to categories 1, 2 and, to a lesser extent, 3, while the treatment of other patients focuses on "care." The provision of conversion therapy for stage IV GC patients might be one of the main roles of surgical oncologists in the near future.

Feasibility of neoadjuvant S-1 and oxaliplatin followed by surgery for resectable advanced gastric adenocarcinoma

PURPOSE

In Japan, the administration of S-1 following D2 gastrectomy is a standard treatment for stage II/III gastric cancer (GC). However, the survival of stage IIIB/IIIC GC remains unsatisfactory. To improve this, we conducted a multicenter phase II study to evaluate the safety and efficacy of a neoadjuvant S-1 and oxaliplatin regimen (SOX) followed by surgery targeted at stage III GC.

METHODS

Oxaliplatin was administered intravenously (130 mg/m(2)) on day 1, and S-1 was administered orally (40 mg/m(2), twice a day) for 14 days followed by a seven-day rest period. After three cycles of therapy, D2 gastrectomy was performed.

RESULTS

A total of 14 patients were enrolled and completed the protocol treatment. Grade 3/4 toxicities included thrombocytopenia (21.4 %), anorexia (14.3 %), and diarrhea (7.1 %). Seven patients (50 %) underwent total gastrectomy, and seven patients underwent distal gastrectomy. Grade 3/4 surgical complications included pancreatic fistula (21.4 %) and lung infection (7.1 %). The pathological response rate was 85.7 %.

CONCLUSION

Although our data are limited and preliminary, neoadjuvant SOX followed by surgery can be performed safely with a high pathological response rate in patients with resectable advanced GC. Further investigation of this neoadjuvant approach is warranted.

A Case of Gastric Cancer with Residual Tumor Only in the Para-Aortic Lymph Nodes after Systemic Chemotherapy followed by Conversion Surgery

We report the case of a 60-year-old male who was diagnosed with gastric cancer. Upper gastrointestinal endoscopy indicated advanced cancer in the posterior wall of the gastric body. Biopsy revealed poorly differentiated adenocarcinoma. Abdominal computed tomography demonstrated thickening of the gastric wall and enlargement of the regional lymph nodes and of the para-aortic lymph nodes (PAN). The involvement of the PAN extended from the celiac axis to the caudal area of the inferior mesenteric artery [cT3N3aH0P0M1(LYM), stage IV]. Systemic chemotherapy was initiated. After 3 courses of S-1 plus cisplatin combination chemotherapy, the primary lesion and the enlarged lymph nodes revealed marked regression except for a minute residual lesion in the lymph nodes. Upon obtaining informed consent, open distal gastrectomy, D2 lymphadenectomy with PAN dissection, and Roux-en-Y reconstruction were performed. The patient was discharged from the hospital 35 days after the operation. Histopathological examination of the resected samples revealed malignant cells only in the PAN, not in the stomach or in the regional lymph nodes [ypT0N0M1(LYM), stage IV]. Currently, the patient is undergoing postoperative adjuvant chemotherapy with S-1 and has remained well without any recurrence after 6 months following surgery.