Tumor Depth Prediction of Gastric Cancer With a T4 Score.

BACKGROUND/AIM: Peritoneal metastases are often found at surgery of pT4 gastric cancers, preventing R0 resection. In the event of successful R0 resection, distant metastases still occur in a sizeable proportion of patients. Estimation of the depth of invasion has a relatively low accuracy (57%-86%) compared with pathological findings. This study sought to develop a clinical score to distinguish between pathological stage T4 (pT4) and pT1-3 gastric cancer. PATIENTS AND METHODS: Reviewing the data of 2,771 patients who had undergone gastrectomy at our hospital from January 1996-December 2016, we assessed demographic factors plus tumor markers, diameter, location, histology, and macroscopic type according to the fifth edition (2019) of the WHO classification. Significant factors on multivariate analysis were used to develop a pT4 gastric cancer depth prediction score (T4 score). RESULTS: Multivariate analysis revealed that the clinical factors associated with pT4 disease were CA19-9 elevation, tumor diameter ≥50 mm, poorly cohesive type adenocarcinoma, mucinous adenocarcinoma, and WHO macroscopic types 2-4. The T4 score was obtained by weighing these factors according to the ß-coefficient. The optimum cutoff value of the T4 score was 4 points. A total of 79.4% of cases with a T4 score ≥4 points were stage pT4. A total of 93.9% of cases with a T4 score <4 points were stage pT1-3, with 91.1% sensitivity, 85.3% specificity, 79.4% positive predictive value, and 93.9% negative predictive value. CONCLUSION: T4 scoring can differentiate pT4 gastric cancer from pT1-3 gastric cancer.

Phase II study of neoadjuvant chemotherapy with S-1 plus oxaliplatin for gastric cancer clinical T4 or N2-3.

In Japan, the standard treatment for stage II or III gastric cancer is D2 gastrectomy followed by administration of S-1 for one year. However, patients with stage III disease have unsatisfactory survival rates. The purpose of this study was to evaluate the efficacy and safety of neoadjuvant chemotherapy consisting of S-1 and oxaliplatin for advanced gastric cancer. Patients with cT4 or cN2-3 gastric cancer were scheduled to receive two courses of chemotherapy (130 mg/m2 oxaliplatin on Day 1, 80 mg/m2 S-1 per day twice daily for 14 days) followed by surgery. The primary endpoint was the R0 resection rate. The secondary endpoints were rates of completion of protocol treatment, pathological response, and adverse events; and 3-year overall survival, 5-year overall survival, and 5-year recurrence-free survival. Between May 2016 and March 2019, 30 patients were enrolled in the study, all of whom completed the protocol treatment. The R0 resection rate (primary endpoint) was 93.3% (95% confidence interval: 77.9-99.2). The pathological response rate was 63.3%. Grade 3-4 toxicities included anemia (3.3%), anorexia (6.7%), and fatigue (3.3%). Relative dose intensities were 91.2% and 94.2% for S-1 and oxaliplatin, respectively. Neoadjuvant S-1 and oxaliplatin is highly effective, achieving an acceptable R0 resection rate with relatively few severe toxicities and good compliance.Trial registration: Registry name: A prospective intervention study on the availability of preoperative SOX therapy for T4 or N2-3 gastric cancer. Trial ID: UMIN: UMIN000024656. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R00002836.

Rapid Flow Cytometry of Gastrointestinal Stromal Tumours Closely Matches the Modified Fletcher Classification.

AIM: We aimed to develop a rapid, simple procedure and an algorithm for quantitative analysis and classification of the metastatic risk of gastrointestinal stromal tumours (GIST) for clinical use. MATERIALS AND METHODS: Eighteen specimens from laparoscopic local gastrectomy were assessed by flow cytometry. We devised a new risk classification for GIST by combining flow cytometry parameters with tumour size and evaluated whether the combined parameters correlated with the modified Fletcher risk classification. RESULTS: We found a significant correlation between clinical prognostic factors (mitotic count and Ki-67 labelling index) and the flow cytometry parameters DNA ploidy, DNA index and S-phase fraction. The combined parameters established from tumour size and the flow cytometry parameters showed a high correlation with the modified Fletcher risk classification (p=0.0064). Flow cytometry had to be performed for approximately 10 minutes to determine the metastatic risk. CONCLUSION: Rapid flow cytometry parameters can classify risk without the need for histological analysis.

Leiomyosarcoma arising from the right ovarian vein.

Leiomyosarcomas (LMS) of the ovarian vein are extremely rare and have a poor prognosis. Only 10 cases have been reported since 1977. The patient is a 69-year-old woman presented with right abdominal pain. Computed tomography showed a regularly shaped tumor, 80 mm in diameter in the retroperitoneum, adjacent to the descending part of the duodenum. Intraoperatively, the right ovarian vein was found to run through the tumor and was, therefore, resected together with the tumor. Pathological examination revealed a LMS of the right ovarian vein. Nine months postoperatively, multiple lung metastases were detected and chemotherapy was initiated. Delayed diagnosis is associated with high mortality. It is important that the diagnosis of LMS should be made preoperatively when you have already diagnosed a tumor to better direct the surgical approach. Multimodal therapy may improve prognosis.

Staging of gastric cancer with the Clinical Stage Prediction score.

BACKGROUND: Chemotherapy with or without surgery is the first-line treatment for stage III/IV gastric cancer, while surgery is the first-line treatment for stage I/II gastric cancer. Accordingly, it is important to distinguish between stage III/IV and stage I/II gastric cancer, but clinical staging is less accurate than pathological staging. This study was performed to develop a clinical score that could distinguish stage III/IV gastric cancer from stage I/II gastric cancer. METHODS: We reviewed 2722 patients who underwent gastrectomy at our hospital from January 1996 to December 2015. As pretreatment factors potentially related to tumor stage, we assessed age, sex, tumor markers, tumor diameter, tumor location, tumor histology, and macroscopic type. Factors showing significance on multivariate analysis were used to develop the Clinical Stage Prediction score (CSP score), and a cutoff value for the score was determined by receiver operating characteristics analysis. RESULTS: According to multivariate analysis, clinical factors associated with stage III/IV disease were elevation of the carcinoembryonic antigen level, tumor diameter ≥ 60 mm, circumferential gastric involvement, esophageal infiltration, mucinous adenocarcinoma, and macroscopic types 2-4. The CSP score was obtained by weighting these factors according to the non-standardized ß-coefficient. Receiver operating characteristics analysis indicated that the optimum cutoff value of the CSP score was 17 points. Among 1042 patients with a CSP score ≥ 17 points, 820 patients (78.7%) had stage III/IV gastric cancer. Conversely, among 1680 patients with a CSP score < 17 points, 1547 patients (92.1%) had stage I/II gastric cancer. When discrimination of stage III/IV gastric cancer from stage I/II gastric cancer by the CSP score was assessed, the sensitivity was 78.7%, specificity was 92.1%, positive predictive value was 86.0%, and negative predictive value was 87.5%. CONCLUSIONS: The CSP score can be helpful for differentiating stage III/IV gastric cancer from stage I/II gastric cancer based on pretreatment clinical factors.

Successful conversion surgery for unresectable gastric cancer with giant para-aortic lymph node metastasis after downsizing chemotherapy with S-1 and oxaliplatin: a case report.

BACKGROUND: Although patients with stage IV gastric cancer who respond well to systemic chemotherapy can be treated with gastrectomy, the prognosis of patients with unresectable gastric cancer with para-aortic lymph node metastasis is poor. We herein report a case of remnant gastric cancer with para-aortic lymph node metastasis that was treated with potentially curative conversion surgery after showing a complete response to chemotherapy with S-1 and oxaliplatin (SOX). CASE PRESENTATION: An 81-year-old man was diagnosed with type 3 remnant gastric cancer with giant para-aortic lymph node metastasis, and he received SOX chemotherapy. After three courses of SOX chemotherapy, the primary tumor and para-aortic lymph node metastases markedly reduced in size, indicating a partial response. Because conversion surgery was possible, the patient underwent total remnant gastrectomy with D2 and para-aortic lymph node dissection. Histological examination revealed no residual cancer cells in the resected stomach and lymph nodes. The patient was diagnosed with a complete pathological response and was discharged on postoperative day 24. Currently, 1 year after surgery, the patient is alive and has not shown any tumor recurrence. CONCLUSION: To the best of our knowledge, this is the first case of advanced remnant gastric cancer with giant para-aortic lymph node metastasis that showed a pathological complete response and favorable outcome after SOX chemotherapy.

Somatic mutations and increased lymphangiogenesis observed in a rare case of intramucosal gastric carcinoma with lymph node metastasis.

BACKGROUND AND AIM: Intramucosal gastric adenocarcinoma of the well-moderately differentiated type only exhibits lymph node metastasis in extremely rare cases. We encountered such case and investigated both the lymphangiogenic properties and somatic mutations in the cancer to understand the prometastatic features of early-stage gastric cancer. METHODS: We quantitatively measured the density of lymphatic vessels and identified mutations in 412 cancer-associated genes through next-generation target resequencing of DNA extracted from tumor cells in a formalin-fixed and paraffin-embedded tissue. Functional consequence of the identified mutation was examined in vitro by means of gene transfection, immunoblot, and the quantitative real-time polymerase chain reaction assay. RESULTS: The intramucosal carcinoma was accompanied by abundant lymphatic vessels. The metastatic tumor harbored somatic mutations in NBN, p.P6S, and PAX8, p.R49H. The PAX8R49H showed significantly higher transactivation activity toward E2F1 than the wild-type PAX8 (P< 0.001). CONCLUSIONS: Our data suggest that increased lymphangiogenesis and somatic mutations of NBN and/or PAX8 could facilitate lymph node metastasis from an intramucosal gastric carcinoma. These findings may potentially inform evaluations of the risk of developing lymph node metastasis in patients with intramucosal gastric cancer.

Constant maintenance of an alternative route of coronary flow in radical surgery for gastric cancer following coronary artery bypass grafting involving the right gastroepiploic artery: a case report.

We describe a 64-year-old man diagnosed as having gastric cancer with a patent right gastroepiploic artery (RGEA) used for coronary artery bypass grafting (CABG). Before gastrectomy, the native coronary artery was revascularized to safely dissect the infrapyloric lymphatic tissue along the layer recently identified as an appropriate layer for radical lymphadenectomy, in anticipation of preserving the radically skeletonized RGEA. The perioperative strategy was feasible. Postoperatively, hemorrhage extended the stopping period of antiplatelet therapy. However, since the RGEA was preserved, an alternative route was available for coronary flow. After a 41-month postoperative follow-up, the patient remained in good health, with no recurrence or cardiac ischemia. In this case, the alternative route of coronary flow could be constantly maintained, although radical infrapyloric lymphadenectomy had been performed. Preoperative revascularization and preserving the RGEA with radical skeletonization can be a safe yet permissibly radical strategy for gastric cancer treatment following CABG involving the RGEA.

A primary tumor of mixed histological type is a novel poor prognostic factor for patients undergoing resection of liver metastasis from gastric cancer.

BACKGROUND: Surgical resection can be an option for the treatment of metastatic liver tumors originating from gastric cancer; however, its prognostic impact is controversial. The aim of this study was to identify prognostic factors in patients with surgical resection of liver metastasis from gastric cancer. METHODS: We retrospectively analyzed the clinicopathological features of 38 consecutive patients undergoing hepatectomy for metastatic tumors from gastric cancer in our institution between 1990 and 2014. RESULTS: The median overall survival of the patients was 28 months. The 5-year survival rate was 33.9%. Primary tumors of a mixed histological type, and residual tumors during the course of treatment were identified as significant independent poor prognostic factors. CONCLUSIONS: Histological evaluation of primary tumors may aid to identify patients suitable for undergoing surgical resection of liver metastasis from gastric cancer.

HER2-positive gastric cancer with paraaortic nodal metastasis successfully resected after chemotherapy with trastuzumab: a case report.

We report on a case of human epidermal growth factor receptor-2 (HER2)-positive gastric cancer with paraaortic lymph node metastasis. The patient (a 49-year-old female) received chemotherapy (capecitabine and cisplatin) plus molecular-targeted therapy (trastuzumab), followed by curative resection. Interestingly, the resected residual cancer was HER2-negative. Intra-tumor heterogeneity hinders molecular-targeted therapy for gastric cancer. In our case, continued trastuzumab administration presented few benefits since the residual cancer cells were HER2-negative. No consensus exists regarding the appropriate therapy for unresectable gastric cancers whose non-curative factors disappear following trastuzumab chemotherapy. The principal options are treatment with surgery or continued chemotherapy with trastuzumab. In our case, resection treated the HER2-negative residual cancer effectively, resulting in curative therapy. This is the first case of positive-to-negative change in the HER2 expression of residual tumor cells following trastuzumab therapy. It suggests that, due to intra-tumor heterogeneity, the risks presented by remnant HER2-negative cancer cells persist despite trastuzumab therapy.