Conversion surgery for stage IV gastric cancer with a complete pathological response to nivolumab: a case report

BACKGROUND

Patients with stage IV gastric cancer have a poor prognosis despite the recent development of multidisciplinary treatments that include chemotherapy. However, conversion surgery has emerged as a promising strategy to improve the prognosis in responders with unresectable gastric cancer after chemotherapy. Moreover, nivolumab is currently recommended as a third-line treatment in patients with unresectable advanced gastric cancer. However, there are few reports of conversion surgery after nivolumab in patients with stage IV gastric cancer.

CASE PRESENTATION

A 68-year-old woman complaining of nausea was diagnosed with stage I gastric cancer (T2N0M0). Although we planned gastrectomy with lymphadenectomy, multiple liver metastases were detected during the surgery. After staging laparoscopy, we diagnosed this patient as having stage IV unresectable gastric cancer, and we administered chemotherapy and immunotherapy for 39 months (first-line regimen: 6 courses of S-1 plus oxaliplatin; second-line regimen: 6 courses of ramucirumab plus paclitaxel; and third-line regimen: 20 courses of nivolumab). Although the liver metastases completely disappeared after the second-line chemotherapy, lung metastases and a rapid enlargement of the primary tumor were confirmed. Consequently, the patient received nivolumab at a dose of 3 mg/kg intravenously every 2 weeks, then a dose of 240 mg/kg intravenously every 2 weeks from September 2018. After 20 courses of nivolumab, the primary tumor dramatically shrank and the lung metastases disappeared. The patient had a partial primary tumor response to nivolumab. Therefore, the patient underwent laparoscopic distal gastrectomy with D2 lymph node dissection. The macroscopic examination of the resected specimen showed an ulcer scar in the primary tumor site. The pathological examination demonstrated no residual tumors and no lymph node metastases, and the histological response of the primary tumor was categorized as grade 3. The postoperative course was uneventful, and the patient is receiving nivolumab to control potential liver and lung metastases.

CONCLUSIONS

Conversion surgery might help control tumor progression in responders after chemotherapy and immunotherapy.

Assessment of sentinel node concept in esophageal cancer based on lymph node micrometastasis

PURPOSE

The clinical significance of lymph node micrometastasis remains unclear in patients with esophageal cancer. Therefore, accurate assessment of lymph node status including micrometastasis is important when performing sentinel node (SN) navigation surgery. The purpose of the present study was to investigate the adequacy of SN concept based on lymph node micrometastasis determined by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) in patients with esophageal cancer.

METHODS

A total of 57 patients with esophageal cancer who were preoperatively diagnosed as having T1-T2 (cT1-T2) and N0 (cN0) were enrolled. They underwent standard esophagectomy with lymph node dissection. One day before surgery, a total of 3 mCi of 99mTechnetium-tin colloid was endoscopically injected into the submucosa around the tumor. During the operation, radioisotope uptake in the lymph nodes was measured using Navigator GPS. All dissected lymph nodes were investigated by RT-PCR using the double marker of CEA and SCC, hematoxylin-eosin (HE) staining, and IHC.

RESULTS

Node-positive incidence identified by HE and IHC was 12.3% (7/57) and 19.3% (11/57), respectively. RT-PCR demonstrated micrometastasis in four of 46 patients without nodal metastasis determined by HE staining and IHC. No non-SN metastases were found in 42 patients without micrometastasis identified by IHC and RT-PCR of SN. Accuracy and false negative rates were 100% (57/57) and 0% (0/42), respectively.

CONCLUSIONS

SN concept might be acceptable in patients with cT1-T2 and cN0 esophageal cancer, even in the presence of micrometastasis identified by IHC and RT-PCR.

Lung recurrence and its therapeutic strategy in patients with pancreatic cancer

BACKGROUND

/Objectives: The lung is a major metastatic site of pancreatic cancer (PC). We aimed to assess the features and prognosis of patients with PC according to the recurrence pattern and the effect of resection of recurrent lung lesion.

METHODS

We enrolled 168 PC patients who had undergone macroscopically curative resection. All resected lung tumors were evaluated immunohistochemically for expressions of thyroid transcription factor-1 (TTF-1) and napsin A.

RESULTS

The most common site of first recurrence was the liver and local site, followed by the lung, peritoneum, and lymph node. Lung recurrence was observed significantly later than was liver recurrence. The median survival time (MST) after recurrence in patients with first recurrence in the lung was significantly longer than MST in patients with first recurrence in the liver (15.2 months vs 5.2 months, p = 0.039). Seven patients with lung recurrence underwent resection of the recurrent lesion. Surgical resection of single metastasis limited to the lung showed favorable overall survival after recurrence (MST = 36.5 months). Patients with single metastasis limited to the lung showed significantly lower value of FDG-PET SUVmax of the primary pancreatic tumor.

CONCLUSIONS

Patients with first recurrence in the lung showed better prognosis than did patients with first recurrence in the liver. Single metastasis limited to the lung could benefit from surgical resection and was significantly associated with lower FDG-PET SUVmax of the primary pancreatic tumor.

Laparoscopic complete mesocolic excision via combined medial and cranial approaches for transverse colon cancer

PURPOSE

To evaluate the safety and feasibility of laparoscopic complete mesocolic excision via combined medial and cranial approaches with three-dimensional visualization around the gastrocolic trunk and middle colic vessels for transverse colon cancer.

METHODS

We evaluated prospectively collected data of 30 consecutive patients who underwent laparoscopic complete mesocolic excision between January 2010 and December 2015, 6 of whom we excluded, leaving 24 for the analysis. We assessed the completeness of excision, operative data, pathological findings, length of large bowel resected, complications, length of hospital stay, and oncological outcomes.

RESULTS

Complete mesocolic excision completeness was graded as the mesocolic and intramesocolic planes in 21 and 3 patients, respectively. Eleven, two, eight, and three patients had T1, T2, T3, and T4a tumors, respectively; none had lymph node metastases. A mean of 18.3 lymph nodes was retrieved, and a mean of 5.4 lymph nodes was retrieved around the origin of the MCV. The mean large bowel length was 21.9 cm, operative time 274 min, intraoperative blood loss 41 mL, and length of hospital stay 15 days. There were no intraoperative and two postoperative complications.

CONCLUSION

Our procedure for laparoscopic complete mesocolic excision via combined medial and cranial approaches is safe and feasible for transverse colon cancer.

Utility of the GeneSearch breast lymph node assay for the rapid evaluation of sentinel lymph nodes in breast cancer

BACKGROUND

The potential for reducing the need for second surgery for axillary lymph node dissection (ALND) has made the intraoperative evaluation of sentinel lymph nodes (SLNs) attractive. The goal of the current study was to evaluate the clinical application of the breast lymph node (BLN) assay, a real-time reverse transcriptase-polymerase chain reaction assay for SLN metastases, by comparing this test with routine pathologic examination.

METHODS

A total of 117 patients with breast cancer underwent breast surgery with SLN biopsy. Each SLN was cut in half along the plane of the longest dimension. Half of each lymph node was examined by the 2 markers of the BLN assay, mammaglobin and cytokeratin 19, and the other half was examined by hematoxylin and eosin staining (H&E) and immunohistochemical staining (IHC) for pancytokeratins.

RESULTS

A total of 204 SLNs were obtained from 117 patients. H&E staining identified metastases in 31 SLNs (15.2%), and IHC staining detected metastases in 6 SLNs; 40 SLNs from 32 patients were found to be positive for metastasis using the BLN assay. The assay results were correlated with the pathologic diagnoses by H&E and IHC staining (P<.001). The sensitivity of the BLN assay compared with pathologic findings classified according to the TNM classification was 95.7% for macrometastases, 60.0% for micrometastases, and 55.6% for isolated tumor cells.

CONCLUSIONS

The 2-marker BLN assay performs in a manner that is comparable to, and analyzes more tissue than, routine pathologic examination. Therefore, clinical intraoperative use of the BLN assay for SLNs may result in a reduction in the need for second surgery for ALND.

Phase II study of S-1 and oxaliplatin as neoadjuvant chemotherapy for locally advanced adenocarcinoma of the gastric or esophagogastric junction: KSCC1601

BACKGROUND

Perioperative chemotherapy is the standard of care for locally advanced gastric cancer (LAGC). This phase II study investigated the efficacy and safety of S-1 and oxaliplatin (SOX) as neoadjuvant chemotherapy (NAC) for LAGC and esophagogastric junction cancer (EGJC).

METHODS

Patients completed up to three cycles of SOX130 (oxaliplatin 130 mg/m2 on day 1, oral S-1 40-60 mg twice daily for 2 weeks every 3 weeks), followed by gastrectomy and D2 lymphadenectomy. The primary endpoint was the pathological response rate (pRR). The anastomosis leakage rate was the secondary endpoint in patients with EGJC, and other secondary endpoints were the R0 resection, overall survival (OS), and relapse-free survival (RFS) rates.

RESULTS

Between April 2016 and July 2017, 47 patients (24 EGJC, 23 LAGC) were enrolled in this study. Forty-two patients (89.4%, 95% confidence interval [CI] = 76.9-96.5) underwent surgery, and R0 resection was achieved in 41 patients. The pRR was 59.5% (90% CI = 45.7-72.3). The major grade 3 or 4 toxicities were appetite loss in six patients (12.8%), thrombocytopenia in five patients (10.6%), and neutropenia and diarrhea in three patients (6.4%) each. The rate of severe anastomotic leakage (Clavien-Dindo classification grade III or higher) in 20 EGJC was 25.0% (90% CI = 10.4-45.6). The 3-year OS and RFS rate were 62.9% (95% CI = 47.2-75.1) and 53.2% (95% CI = 38.1-66.2), respectively.

CONCLUSION

SOX130 demonstrated substantial benefit for LAGC and EGJC. However, special attention should be paid to anastomotic leakage during surgery for EGJC.

Clinical Impact of Stomach-partitioning Gastrojejunostomy with Braun Enteroenterostomy for Patients with Gastric Outlet Obstruction Caused by Unresectable Gastric Cancer

AIM

To compare adverse events and post-therapeutic clinical courses between stomach-partitioning gastrojejunostomy with Braun enteroenterostomy (SPGJ-BEE) and endoscopic metallic stent placement (EMSP) in patients with gastric outlet obstruction (GOO) caused by unresectable gastric cancer and assess the clinical utility of SPGJ-BEE.

PATIENTS AND METHODS

We retrospectively reviewed clinical data of 16 and 9 patients with GOO undergoing SPGJ-BEE and EMSP, respectively.

RESULTS

Re-obstruction caused by tumor overgrowth was identified in 3 (33.3%) out of 9 patients in the EMSP group. The GOO scoring system (GOOSS) revealed that its score after treatments was significantly higher in the SPGJ-BEE group than in the EMSP group (p<0.001). All patients in both groups received chemotherapy after treatments. The median survival times in the SPGJ-BEE and EMSP groups were 414 and 303 days, respectively.

CONCLUSION

Our preliminary results suggest that SPGJ-BEE provides an improved long-term quality of life and the early induction of subsequent chemotherapy related with a better prognosis in patients with GOO.

Clinical significance of circulating tumor cells in the response to trastuzumab for HER2-negative metastatic gastric cancer

PURPOSE

The prognosis of metastatic gastric cancer has improved due to trastuzumab in patients with HER2 positive. Circulating tumor cells (CTCs) have been examined as a prognostic predictor in gastric cancer. The clinical advantage of trastuzumab was examined in gastric cancer patients with HER2-negative tumor tissues and HER2-positive CTCs.

METHODS

A total of 105 patients with metastatic or recurrence gastric cancer were enrolled. All patients were examined HER2 expression in CTC using the CellSearch system in blood specimens.

RESULTS

CTCs were detected in 65 of 105 patients (61.9%) and 61 patients were divided into three groups: Group A (n = 27), histological HER2-positive; Group B (n = 17), histological HER2-negative and HER2-positive CTCs; and Group C (n = 17), HER2-negative on histology and CTCs. Patients received capecitabine plus cisplatin. Groups A and B were additionally treated by trastuzumab. There was no relationship between tumor tissues and CTCs in HER2 expression. Even if group B had no histological HER2 expression, group B showed a good prognosis as same as group A, and group C had a significantly worse overall survival than groups A and B. The multivariate analysis demonstrated that HER2-expression on CTCs was an independent prognostic factor for both overall and progression-free survival.

CONCLUSION

The present results indicate the potential clinical utility of trastuzumab combined chemotherapy in patients with HER2-positive CTCs even if they are histologically HER2-negative.

Indication and Prognostic Significance of Conversion Surgery in Patients with Liver Metastasis from Gastric Cancer

OBJECTIVE

Chemotherapy is generally recommended as the first-line standard treatment in patients with liver metastasis from gastric cancer. However, the clinical impact of surgical treatment remains unclear in responders after chemotherapy. The present study aimed to investigate the tumor response and prognosis after chemotherapy and to assess the clinical indication of conversion surgery in responders.

METHODS

The study retrospectively reviewed the clinical data of 44 patients with liver metastasis from gastric cancer who were treated with chemotherapy between February 2002 and January 2019. These patients were classified into progressive disease (PD) and non-PD groups according to tumor response.

RESULTS

Among the 44 patients, 7 and 26 had peritoneal dissemination and ≥5 had metastatic liver nodules. Additionally, 15 and 29 patients had PD and non-PD, respectively. Surgical treatment was significantly correlated with tumor response (p < 0.0321). Prognostic differences between the PD and non-PD groups were significant (p < 0.0001). Moreover, gastrectomy and hepatectomy were significantly correlated with the number of liver metastases (≥5 vs. <5, respectively) in the non-PD group (p = 0.0025 and p = 0.0169, respectively). The 3-year survival rates among patients with non-PD undergoing both gastrectomy and hepatectomy (n = 6), gastrectomy alone (n = 7), and nonsurgical treatments (n = 16) were 100, 66.7, and 0%, respectively (p = 0.0026). Multivariate analysis identified peritoneal dissemination as an independent prognostic factor (p = 0.0225).

CONCLUSION

Our preliminary results suggest that conversion surgery for gastric cancer with liver metastasis might be clinically indicated in chemotherapy responders with <5 metastatic liver nodules and without peritoneal dissemination.

Radial incision and cutting method using a transanal approach for treatment of anastomotic strictures following rectal cancer surgery: a case report

BACKGROUND

Development of an anastomotic stricture following rectal cancer surgery is not uncommon. Such strictures are usually managed by manual or instrumental dilatation techniques that are often insufficiently effective, as evidenced by the high recurrence rate. Various surgical procedures using minimally invasive approaches have also been reported. One of these procedures, endoscopic radial incision and cutting (RIC), has been extensively reported. However, RIC by transanal minimally invasive surgery (TAMIS) is yet to be reported. We here report a novel application of TAMIS for performing RIC for anastomotic rectal stenosis.

CASE PRESENTATION

A 67-year-old man had suffered from constipation for 6 years after undergoing low anterior resection for stage II rectal cancer 7 years ago. Colonoscopy showed a 1-cm diameter stricture in the lower rectum. Balloon dilatation was performed many times because of repeated recurrences. Thus, surgical management was considered and the stricture was successfully excised via a RIC method using a TAMIS approach. Postoperatively, the patient had minimal leakage that resolved with conservative treatment.

CONCLUSIONS

A RIC method using a TAMIS approach is an effective minimally invasive means of managing anastomotic strictures following rectal cancer surgery.

Role of 18F-FDG-PET/CT in Esophageal Squamous Cell Carcinoma After Neoadjuvant Chemoradiotherapy

AIM

The aim of this study was to assess the role of 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) in predicting pathological response and survival in patients with esophageal squamous cell carcinoma (ESCC) treated with neoadjuvant chemoradiotherapy (nCRT).

PATIENTS AND METHODS

Thirty patients with advanced ESCC received nCRT followed by surgery, and underwent FDG-PET/CT twice before and after nCRT. We compared the results of FDG-PET/CT with the pathological results and prognosis.

RESULTS

Pathological response was found to correlate with the maximum standardised uptake value (SUVmax) after nCRT and the rate of decrease of SUVmax Using univariate analysis, pN, SUVmax after nCRT and the rate of decrease of SUVmax were found to be prognostic factors. Multivariate analysis revealed that only pN was an independent prognostic factor.

CONCLUSION

The prediction of pathological response and prognosis using FDG-PET/CT is not as reliable as pathological detection of lymph node metastasis, but could be a useful method contributing to treatment decisions.

Laparoscopic complete mesocolic excision via mesofascial separation for left-sided colon cancer

PURPOSE

To evaluate the safety and feasibility of laparoscopic complete mesocolic excision (CME) via mesofascial separation for left-sided colon cancer.

METHODS

We evaluated prospectively collected data on 65 consecutive patients with stage I-III left-sided colon cancer, who underwent laparoscopic CME between October 2011 and September 2016. After the exclusion of 5 patients who had T4b or other active tumors, 60 patients were the subjects of this analysis. The completeness of CME, preservation of the hypogastric nerve, operative data, pathological findings, complications, and length of hospital stay were assessed.

RESULTS

CME completeness was graded as the mesocolic and intramesocolic plane in 54 and 6 patients, respectively. The hypogastric nerve was preserved in all patients. A total of 17, 12, 28, and 3 patients had T1, T2, T3, and T4a tumors, respectively. The mean number of lymph nodes retrieved was 16.2, and lymph node metastasis was identified in 22 patients. The mean operative time and intraoperative blood loss were 283 min and 38 ml, respectively. One patient had an intraoperative complication and six patients had postoperative complications. The hospital stay was 12 days.

CONCLUSION

Laparoscopic CME via mesofascial separation is a safe and feasible procedure for left-sided colon cancer.

Sentinel node mapping for post-endoscopic resection gastric cancer: multicenter retrospective cohort study in Japan

BACKGROUND

Standard gastrectomy with systematic lymphadenectomy as an additional surgery after endoscopic resection (ER) causes a deterioration in long-term quality of life. If the sentinel lymph node (SN) basin concept can be applied in post-ER gastric cancer, minimal surgery can be applied without reducing the curability. This retrospective multicenter cohort study aimed to verify the validity of the SN basin concept in post-ER gastric cancer.

PATIENTS AND METHODS

Individual data of 132 patients who underwent SN mapping after ER were collected from 8 university hospitals in Japan from 2001 to 2016. Tracers were injected endoscopically in the submucosal layer at four sites around the post-ER scar. We compared the SN basin distribution of post-ER gastric cancer with that of 275 patients with non-ER gastric cancer.

RESULTS

Two cases of SN were unidentified, both involving a single tracer (SN detection rate: 98.5%). Nine cases (6.8%) of lymph node metastasis were found, of which eight had a metastatic lymph node within the SNs and one had a non-SN metastasis within the SN basin. The diagnostic sensitivity of SN mapping for lymph node metastasis was 88.9% in post-ER group and 95.7% in non-ER group (P = 0.490); the accuracy was 99.2% and 99.6% (P = 0.539), respectively. Regarding the SN basin, no significant intergroup differences were found regardless of the primary tumor location.

CONCLUSIONS

Our findings clarified the feasibility of SN mapping based on the SN basin concept in patients with gastric cancer who previously underwent ER.

Clinical-pathological implication of human leukocyte antigen-F-positive gastric adenocarcinoma

BACKGROUND

Human leukocyte antigen (HLA)-F is a nonclassical HLA class I molecule that shows aberrant expression in cancer cells. Although the clinical implications of HLA-F expression in cancer patients have been described, the specific significance of this antigen in gastrointestinal cancer remains unclear. The present study examined the expression pattern and clinical implications of HLA-F in gastric adenocarcinoma.

PATIENTS AND METHODS

HLA-F expression was assessed in 179 patients by immunohistochemistry, and its association with clinical parameters including patient survival was analyzed.

RESULTS

HLA-F expression was positive in 30.7% (55/179) of patients and in 50.0% (90/179) of peritumoral infiltrating lymphocytes. HLA-F expression in gastric adenocarcinoma was significantly correlated with the depth of invasion, nodal involvement, and lymphatic and venous invasions (P < 0.01, all). HLA-F positivity of infiltrating cells near the tumor showed no correlation with clinicopathological features. HLA-F-positive patients had a significantly worse prognosis than HLA-F-negative patients (P = 0.012). However, HLA-F expression was not an independent prognostic factor in multivariate analysis.

CONCLUSIONS

The present study provides the first evidence that neo-HLA-F expression is of clinical significance in gastric adenocarcinoma. HLA-F expression in gastric adenocarcinoma may promote the aggressive behavior of tumors by suppressing the activity of antitumor immune effector cells.

Histological findings of an autologous dermal fat graft implanted onto the pectoralis major muscle of a rat model

BACKGROUND

The aim of this study was to investigate the maintenance of volume as a spacer by comparing vascular supply and apoptosis in an implanted autologous-free dermal fat graft (FDFG) and free fat graft (FFG). An autologous FDFG is a material used in plastic surgery and oncoplastic breast surgery that is ideal for immediate volume replacement after partial mastectomy because of its easy availability and minimal invasion of the donor site; however, immunohistochemical findings and survival procedures have not yet been reported.

METHODS

An experimental protocol using a unique animal model was designed for the present study. The expression of vascular endothelial growth factor (VEGF) was measured in FDFGs and FFGs implanted onto the pectoral major muscle of Wistar rats. Thirty Wistar rats were divided into two groups and postoperatively 1, 2, 4, 8, and 16 weeks (POW1, 2, 4, 8, 16). Six samples from three rats in each group were used as control samples (POW0).

RESULTS

The thickness of the implanted FDFG was not significantly different from the control sample at POW1, 2, 4, 8, and 16 between FDFG and FFG group; however, the thickness at POW8 and 16 was significantly lesser in the FFG group than in the control samples. The average proportion of fatty tissue to whole tissue ranged from 34.2 to 48.6 % in the FDFG group and from 57.2 to 76.7 % in the FFG group during the observation period; however, there was no significant difference in the proportion of fatty tissue between these two groups. There were no significant differences between the average number of VEGF-positive cells in the FDFG group and the FFG group at POW1, 2, 4, 8, and 16. The average number of TUNEL-positive cells in the early period at POW1 was significantly lower in the FDFG group than in the FFG group.

CONCLUSIONS

This rat model was useful for investigating the mechanisms of angiogenesis, apoptosis, structure maintenance, and fibromatous changes. From the present experimental study, we believe that FDFG is one of the most convenient materials currently available to repair small defects at the time of BCS even in the clinical field.

Clinical significance of mediastinoscope-assisted transhiatal esophagectomy in patients with esophageal cancer

PURPOSE

Mediastinoscope-assisted transhiatal esophagectomy (MATHE) is a useful surgical procedure in esophageal cancer patients who have limited indications for transthoracic operations due to preoperative complications.

METHODS

In the last 10 years, 63 patients underwent MATHE at our department. We examined the clinical data of these patients and assessed the indications, postoperative outcomes, and prognostic factors of MATHE.

RESULTS

The 5-year overall survival (OS) rate was 53.4 %, and disease-free survival (DFS) rate was 66.0 %. Postoperative complications were observed in 22 cases (34.9 %), and recurrent disease occurred in 17 cases (27.0 %). On univariate analyses of OS, location of the tumor, tumor depth, lymph node metastasis, clinical stage, simultaneous resection of other organs, postoperative pneumonia, and blood loss were significant prognostic factors. On multivariate analyses, location of the tumor and lymph node metastasis were independent prognostic factors of OS. On univariate analyses, location of the tumor, tumor depth, lymph node metastasis, clinical stage, and blood loss were significant prognostic factors of DFS, while on multivariate analyses of DFS, lymph node metastasis and blood loss were independent prognostic factors.

CONCLUSION

MATHE is a useful procedure for the middle to lower thoracic esophageal cancer patients without clinical lymph node metastasis with serious complications who were unable to undergo thoracotomy.

Response Rate and Prognostic Impact of Salvage Chemotherapy after Nivolumab in Patients with Advanced Gastric Cancer

OBJECTIVE

Nivolumab is recommended as a third-line treatment in patients with unresectable advanced or recurrent gastric cancer. Although recent studies have demonstrated the prognostic impact of salvage chemotherapy after immune checkpoint inhibitors in several malignancies, its clinical significance remains unclear in patients with gastric cancer. This study aimed to investigate tumor response to subsequent chemotherapy after nivolumab in patients with advanced gastric cancer and assess the prognostic effect of salvage chemotherapy.

METHODS

We retrospectively enrolled 31 patients with unresectable advanced or recurrent gastric cancer receiving nivolumab.

RESULTS

Twenty-two and nine patients received nivolumab as third-line and fourth- to sixth-line treatments, respectively. The objective response rate (ORR) and disease control rate (DCR) to nivolumab were 20.0% (4/20) and 55.0% (11/20), respectively. Eleven patients received salvage chemotherapy after nivolumab. The ORR and DCR to salvage chemotherapy were 37.5% (3/8) and 75.0% (6/8), respectively. The median progression-free survival and overall survival following salvage chemotherapy were 285 and 360 days, respectively.

CONCLUSION

Our preliminary study indicates that nivolumab exposure may enhance subsequent chemosensitivity in patients with advanced gastric cancer.

Expression of gremlin1 in gastric cancer and its clinical significance

As an antagonist of bone morphogenetic proteins (BMPs), 2, 4 and 7, gremlin1 plays a role in regulating organogenesis, tissue differentiation and angiogenesis. However, there is little information regarding gremlin1 in gastrointestinal cancer. We attempted to clarify how gremlin1 expression affects the clinical features and biological properties of gastric cancer. A total of 232 gastric cancer patients who received R0 gastrectomy at Kagoshima University Hospital were enrolled. Gremlin1 expression in gastric cancer was detected by immunohistochemical and western blotting methods. Correlations between clinicopathological parameters and gremlin1 expression were analyzed. Gremlin1 was identified in the cytoplasm and nucleus of all gastric cancer cell lines and some regions of surgical specimens of gastric cancer. One hundred and seventeen of the 232 patients (50.4%) were classified as gremlin1-positive based on gremlin1 expression. Gremlin1 positivity was correlated with shallower tumor depth, smaller tumor size, less nodal involvement and vessel invasion (p < 0.05). The 5-year survival rate of the gremlin1-positive group was 81%, which was significantly higher than the gremlin1-negative group (p < 0.01). Multivariate analysis revealed that gremlin1 was not selected as an independent prognostic marker. Gremlin1 expression in gastric cancer may be a useful prognostic marker that is involved with the BMP signaling pathway. Furthermore, gremlin1 may have clinical use as a diagnostic and treatment tool.

Clinical application and outcomes of sentinel node navigation surgery in patients with early gastric cancer

Sentinel node navigation surgery (SNNS) has been recognized as a minimally invasive tool for individualized lymphadenectomy in patients with early gastric cancer (EGC). The aim of this study was to compare clinicopathological factors, adverse events, and clinical outcomes between sentinel node mapping (SNM) and SN dissection (SND) groups and assess the clinical utility of SNNS in patients with EGC. The clinical data of 157 patients with EGC, diagnosed as clinical T1N0M0 with tumors ≤ 40 mm, undergoing SNNS between March 2004 and April 2016 were retrospectively reviewed. Twenty-seven patients were excluded from the analysis. In the remaining 130 patients, 59 and 71 patients underwent standard lymphadenectomy for SNM and SND, respectively. The sentinel node detection rate in the SNM and SND groups was 98.3% (58/59) and 100% (71/71), respectively. Two (3.5%), 15 (25.9%), and 41 (70.7%) patients having sentinel nodes underwent total gastrectomy, proximal gastrectomy (PG), and distal gastrectomy (DG), respectively, in the SNM group. One (1.4%), 5 (7.0%), 10 (14.1%), 39 (54.9%), and 16 (22.5%) patients underwent PG, DG, segmental gastrectomy, local resection, and endoscopic submucosal dissection, respectively, in the SND group. There was no significant difference in postoperative complications between the SNM and SND groups (P = 0.781). Survival did not differ between the both groups (P = 0.856). The present results suggest that personalized surgery with SND provides technical safety and curability related with a favorable survival outcome in patients with EGC.

The clinical usefulness of the intraoperative detection of sentinel lymph node metastases by a rapid RT-PCR system in patients with gastric cancer

BACKGROUND

The incidence of pathological lymph node metastases in patients with gastric cancer is 5% to 10%, which means that approximately 90% of patients with gastric cancer may undergo unnecessary lymphadenectomy. The precise intraoperative diagnosis of sentinel lymph node (SN) metastases is essential. The purpose of the current study was to verify the usefulness of a rapid reverse transcriptase-polymerase chain reaction (RT-PCR) system compared with hematoxylin and eosin staining for such diagnoses.

METHODS

A total of 113 patients with clinical T1-T2 (cT1-T2) gastric cancer, including 73 patients with cT1cN0 disease with a tumor diameter <4 cm, were enrolled in the current study. SNs were identified by a radioisotope method. Carcinoembryonic antigen and cytokeratin 19 were used as markers for RT-PCR and the cutoff values were set using 1701 lymph nodes harvested from 157 patients with gastric cancer.

RESULTS

SNs were detected in all 113 patients. Sensitivity and accuracy for detection by paraffin section were both 100% in patients with cT1 disease and were 60% and 90%, respectively, in patients with cT2 disease. The sensitivity of RT-PCR for the detection of pathological SN metastases was 92.3%. Furthermore, 11 patients had SN metastases detected only by RT-PCR, and these patients had frequent lymphatic invasion. Hematoxylin and eosin staining detected SN metastases in 6 of 73 patients with cT1cN0 gastric cancer; RT-PCR and frozen section detected SN metastases in 6 and 4 of these patients, respectively. Accordingly, the sensitivity of RT-PCR and frozen section for the detection of those pathological SN metastases were 100% and 66.6%, respectively.

CONCLUSIONS

The rapid RT-PCR system appears to have clinical usefulness for the intraoperative detection of SN metastases in patients with gastric cancer.

Clinical significance of circulating tumor cells in blood from patients with gastric cancer

Circulating tumor cells (CTC) have been focused on as a target for detecting occult tumors, predicting therapeutic responses and prognoses, and monitoring postoperative recurrence in the clinical management of patients with various malignancies, including gastric cancer. Recent advances in molecular diagnostic tools have contributed to high sensitivity and specificity for the detection of CTC. A conspicuous disparity exists in the incidence of CTC among studies. However, a close relationship has been reported between positivity for CTC and well-known prognostic clinicopathological factors including depth of tumor invasion, lymph node metastasis, stage, and lymphatic and venous invasion in patients with gastric cancer. According to most studies published on the clinical impact of CTC, the presence of CTC negatively affects the prognosis of patients with gastric cancer. Moreover, the study of CTC based on a meta-analysis demonstrated their importance as a poor prognostic indicator. In clinical management, pre- and post-therapeutic monitoring of CTC using liquid biopsy may be useful for early detection of subclinical patients or disease recurrence, prediction of tumor progression, and administrative control of adjuvant chemotherapy. Although their functional properties remain unclear, molecular profiling of CTC may contribute to the development of personalized treatment that effectively inhibits tumor progression in patients with advanced gastric cancer. We herein review the clinical significance of CTC as a promising blood marker and therapeutic target in patients with gastric cancer.

Vascular endothelial growth factor inhibitors promote antitumor responses via tumor microenvironment immunosuppression in advanced colorectal cancer

PURPOSE

This study aims to investigate changes in the tumor immune environment of patients who underwent therapy with a vascular endothelial growth factor (VEGF) inhibitor for advanced colorectal cancer.

METHODS

Patients (n = 135) with T3 or T4 colorectal cancer were included in this retrospective study. They were classified as follows: patients who had not received preoperative treatment (UPFRONT group, n = 54), who had received FOLFOX as preoperative chemotherapy (FOLFOX group, n = 55), and who had undergone resection after combination FOLFOX and bevacizumab as unresectable colorectal cancer (B-MAB group, n = 26). The number of cytotoxic T lymphocytes (CTLs), FOXP3+ lymphocytes (including regulatory T cells (Tregs)), CD163+ monocytes (including M2-type tumor-associated macrophages (TAM-M2 type)), and programmed cell death 1 (PD-1)+ lymphocytes was evaluated immunohistochemically in the cancer cell area (CC) and stromal cell area (ST) of surgical specimens, and compared among the three groups.

RESULTS

The CTL population did not differ among the three groups in both areas. In the B-MAB group, the numbers of PD-1+ cells in the ST, FOXP3+ lymphocytes in both areas, and CD163+monocytes in the ST was lower than that in the other two groups, and a correlation with the histological therapeutic effect was observed.

CONCLUSIONS

In advanced colorectal cancer, VEGF inhibitors may decrease the number of PD-1+ cells and inhibit the infiltration of FOXP3+ lymphocytes and CD163+monocytes into the tumor environment.

Utility of the sentinel node concept for detection of lateral pelvic lymph node metastasis in lower rectal cancer

BACKGROUND

There are two lymphatic flows in lower rectal cancer; one along the inferior mesenteric artery and another towards the internal iliac artery. The benefit of dissection of lateral pelvic (LP) lymph nodes (LPLN) remains controversial. This study aimed to clarify the possibility of detecting the sentinel node (SN) of the LP region (LPSN) and examine metastasis, including micrometastasis, using a radio isotope (RI) method.

METHODS

In total, 62 patients with clinical (c)T1-T4 rectal cancer were enrolled in this study (11, 16 and 35 patients had tumor located in the upper, middle and lower rectal third, respectively). LPSNs were detected using a radio-isotope method in which 99 m technetium-tin colloid was endoscopically injected into the submucosa in patients with cT1, and into the muscularis propria in patients with cT2, cT3 and cT4. All patients underwent curative resection with lymphadenectomy. LPSN metastases were diagnosed by HE staining, immunohistochemical staining using AE1/AE3 as a primary antibody and by RT-PCR using CEA as a marker.

RESULTS

Of the lower rectal (c)T2-4 tumors, 38.4% had lateral pelvic lymphatic flow that was significantly greater than that of cT1 tumors in the upper and middle thirds of the rectum (p = 0.0074). HE and immunohistochemical staining did not detect LPSN metastases but RT-PCR detected micrometastasis of three SNs. The remaining half of LPSNs were immunohistochemically re-examined; in all three cases, isolated tumor cells were detected.

CONCLUSION

The SN concept may be useful for detecting lateral pelvic lymphatic flow and LPSN metastases, including micrometastasis in lower rectal cancer.

Correlation Between Biomarker Candidate Proteins with the Effect of Neoadjuvant Chemoradiation Therapy on Esophageal Squamous Cell Carcinoma

BACKGROUND

While chemoradiation therapy (CRT) is one of the most useful treatments for esophageal squamous cell carcinoma (ESCC), it is important to predict response prior to treatment by using markers because some patients respond well and others do not.

METHODS

Fifty-nine patients with ESCC were treated with neoadjuvant CRT at the Kagoshima University Hospital. The expression of seven types of biomarker candidate proteins in biopsy specimens of untreated primary tumors was evaluated to determine whether it correlated with response and prognosis.

RESULTS

The positive expression rates were 47% for p53, 83% for CDC25B, 68% for 14-3-3sigma, 76% for p53R2, 75% for ERCC1, 32% for Gli-1, and 54% for Nrf2. In terms of histological response, tumor grade of the 59 patients was 48.8% for grade 1 as the non-responder, 29.2% for grade 2, and 22.0% for grade 3 as the responder. CRT was significantly effective in p53(-), p53R2(-), ERCC1(-), and Nrf2(-) tumors, while p53(-), p53R2(-), and ERCC1(-) were factors independently correlated with effective histological response. Their combined expression of two or three negative expressions had 100% effective response and was a significant prognostic factor.

CONCLUSION

Our results suggest that two or three negative expressions of p53, p53R2, and ERCC1 in biopsy specimens of primary tumors were associated with a favorable response to CRT for ESCC. Assessment of tumor suppressor and DNA repair protein expressions in biopsy specimens may be useful for the potential utility of CRT therapy for patients with ESCC prior to treatment.

Clinical impact of creatine phosphokinase and c-reactive protein as predictors of postgastrectomy complications in patients with gastric cancer

BACKGROUND

Postoperative complications have been linked to the morbidity and mortality of several cancers. However, predicting whether complications will occur in the early period after surgery or not is challenging. Hence, this study aimed to examine the diagnostic accuracy of serum creatine phosphokinase (CPK) and c-reactive protein (CRP) in predicting the development of postgastrectomy complications.

METHODS

We retrospectively analyzed 188 patients with gastric cancer (GC) who underwent gastrectomy. The diagnostic accuracy of serum CPK and CRP was investigated using the areas under the curves (AUC). The CPK ratio was defined as the CPK on postoperative day (POD) 1 to the CPK on a preoperative day.

RESULTS

Out of 188 patients, 48 (25.5%) developed postoperative complications. The complications group had a greater operative time (p = 0.037), higher CPK ratio on POD1 (p < 0.0001), and a higher serum CRP level on POD3 (p = 0.001). The AUC for the CPK ratio was 0.772, with an optimal cutoff value of 7.05, whereas that for CRP was 0.659, with an optimal cutoff value of 11.4 mg/L. The CPK ratio on POD1 (p < 0.0001) and the CRP on POD3 (p = 0.007) were independent factors for predicting the development of postgastrectomy complications. The CPK ratio on POD1 and the CRP on POD3 predicted postgastrectomy complications in 41 patients (85.4%). According to combined value of both CPK ratio and CRP level, the positive predictive value and the negative predictive value was 0.70 and 0.829. And sensitivity and specificity were 0.438 and 0.936.

CONCLUSION

The CPK ratio on POD1 and the CRP on POD3 after gastrectomy for GC were predictive factors for complication development and may be employed to prevent the development of such complications and improve the prognosis of patients with GC.