Circulating Exosomal MicroRNA Signature Predicts Peritoneal Metastasis in Patients with Advanced Gastric Cancer.

BACKGROUND: Despite a radical operation, about half of gastric cancer (GC) patients with advanced GC experience peritoneal metastasis (PM), and the patients with PM have a poor prognosis. However, because staging laparoscopy was a highly invasive procedure for patients, identification of PM using a liquid biopsy can be useful for patients with GC. METHODS: This study analyzed two genome-wide miRNA expression profiling datasets (GSE164174 and TCGA). The study prioritized biomarkers in pretreatment plasma specimens from clinical training and validation cohorts of patients with GC. The authors developed an integrated exosomal miRNA panel and established a risk-stratification model, which was combined with the miRNA panel and currently used tumor markers (CEA, CA19-9, CA125, and CA72-4 levels). RESULTS: The comprehensive discovery effort identified a four-miRNA panel that robustly predicted the metastasis with excellent accuracy in the TCGA dataset (area under the curve [AUC] 0.86). A circulating exosomal miRNA panel was established successfully with remarkable diagnostic accuracy in the clinical training (AUC 0.85) and validation (AUC 0.86) cohorts. Moreover, the predictive accuracy of the panel was significantly superior to that of conventional clinical factors (P < 0.01), and the risk-stratification model was dramatically superior to the panel and currently used clinical factors for predicting PM (AUC 0.94; univariate: odds ratio [OR] 77.00 [P < 0.01]; multivariate OR 57.71 [P = 0.01]). CONCLUSIONS: The novel risk-stratification model for predicting PM has potential for clinical translation as a liquid biopsy assay for patients with GC. The study findings highlight the potential clinical impact of the model for improved selection and management of patients with GC.

Prognostic impact of the combination of p16INK4a, p21 and Immunoscore in rectal cancer.

BACKGROUND: The association between p16INK4a and p21, a marker of cellular senescence, and the Immunoscore, an immunological prognostic indicator, in rectal cancer patients undergoing curative surgery were investigated. METHODS: A total of 82 patients who underwent curative surgery for rectal cancer were evaluated. The resected specimens were analyzed for p16INK4a, p21, CD3 and CD8 expression by immunohistochemistry. Immunoscore was calculated on the basis of CD3 and CD8 expressions. The clinicopathological characteristics and long-term outcomes were evaluated. RESULTS: Among the 82 patients, 24 (29.3%) were p16INK4a-positive and 11 (13.4%) were p21-positive. The patients were classified into the following five Immunoscore groups (IS0-5). IS0, IS1 and IS2 were classified as the low Immunoscore group (45 patients, 54.9%) and IS3 and IS4 as the high Immunoscore group (37 patients, 45.1%). There was no significant difference in age, sex, body mass index, American Society of Anesthesiologists physical status, depth of invasion of the tumor, lymph node metastasis and histological classification of the tumor with p16INK4a or p21 expression or Immunoscore. p16INK4a-positive expression and low Immunoscore each showed a tendency to indicate poor prognosis of disease-free survival (DFS). Patients with the combination of p16INK4a and p21 positivity and with p16INK4a positivity and low Immunoscore showed significantly poor prognosis of DFS. Patients with p21 positive positivity and low Immunoscore tended to have worse DFS. CONCLUSIONS: p16INK4a, p21 and Immunoscore may be prognostic indicators of rectal cancer. The combination of them may provide more accurate prognostic prediction than either factor alone.

Blue light irradiation inhibits the M2 polarization of the cancer-associated macrophages in colon cancer.

Recent studies have shown that blue light-emitting diode (LED) light has anti-tumor effects, suggesting the possibility of using visible light in cancer therapy. However, the effects of blue light irradiation on cells in the tumor microenvironment, including tumor-associated macrophages (TAMs), are unknown. Here, THP-1 cells were cultured in the conditioned medium (CM) of HCT-116 cells to prepare TAMs. TAMs were divided into LED-irradiated and control groups. Then, the effects of blue LED irradiation on TAM activation were examined. Expression levels of M2 macrophage markers CD163 and CD206 expression were significantly decreased in LED-irradiated TAMs compared with the control group. While control TAM-CM could induce HCT-116 cell migration, these effects were not observed in cells cultured in TAM-CM with LED irradiation. Vascular endothelial growth factor (VEGF) secretion was significantly suppressed in LED-exposed TAMs. PD-L1 expression was upregulated in HCT-116 cells cultured with TAM-CM but attenuated in cells cultured with LED-irradiated TAM-CM. In an in vivo model, protein expression levels of F4/80 and CD163, which are TAM markers, were reduced in the LED-exposed group. These results indicate that blue LED light may have an inhibitory effect on TAMs, as well as anti-tumor effects on colon cancer cells.

Feasibility of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor with tumor diameter of >5 cm.

BACKGROUND: Laparoscopic and endoscopic cooperative surgery (LECS) is an effective treatment for gastric gastrointestinal stromal tumors (GISTs). The utility of LECS for gastric GISTs of > 5 cm remains controversial. This study was performed to investigate the feasibility of LECS for gastric GISTs with a tumor diameter of >5 cm. METHODS: We analyzed 43 patients with gastric GISTs who underwent LECS or laparoscopic partial gastrectomy (Lap-Partial Gx). We compared the surgical outcomes of LECS versus Lap-Partial Gx and of LECS for a tumor diameter of > 5 versus ≤ 5 cm. RESULTS: In the comparison of LECS versus Lap-Partial Gx, there were no significant intergroup differences in the operative time or blood loss volume. The morbidity rate was similar between the groups. No postoperative mortality occurred in either group. In the comparison of LECS for a tumor diameter of > 5 versus ≤ 5 cm, there were no significant intergroup differences in operative time, or blood loss volume. The morbidity rate was similar between the > 5-cm and ≤ 5-cm groups (0.0% vs. 4.5%, respectively ; p = 0.56). Additionally, no recurrence or death occurred during follow-up in either group. CONCLUSION: LECS is a feasible option for gastric GISTs with a tumor diameter of > 5 cm. J. Med. Invest. 71 : 148-153, February, 2024.

Number of Healthy Teeth Can Predict the Response of Rectal Cancer to Chemoradiotherapy: A Retrospective Study.

BACKGROUND: It has been reported that the oral and gut microbiomes are associated with the prognosis in patients who undergo surgery, chemotherapy, and radiation for colorectal cancer. This study is the first to identify a correlation between the number of healthy teeth, which is an oral health indicator, and the efficacy of preoperative chemotherapy for rectal cancer. METHODS: This retrospective single-center study included 30 patients who underwent radical surgery after preoperative chemoradiotherapy (CRT) between December 2013 and June 2021. The relationship between number of teeth before CRT and the efficacy of CRT, CRT-related adverse events, postoperative complications, and long-term postoperative outcomes was examined. RESULTS: The number of healthy teeth was significantly greater in patients with downstaging of their disease than in those without downstaging (P = .027) and in patients with a complete response according to the Response Evaluation Criteria in Solid Tumors than in those who did not have a complete response (P = .014). Patients were divided into two groups according to whether they had ≥15 teeth or ≤14 teeth. There was no significant between-group difference in CRT-related adverse events. The incidence of all postoperative complications and grade II postoperative complications tended to be higher in patients with ≥15 teeth (P = .071 and P = .092, respectively), as did the 5-year overall survival rate (P = .083) and the 5-year disease-free rate (P = .007). DISCUSSION: The number of healthy teeth predicted the response to preoperative CRT, postoperative complications, and the outcome of subsequent surgery in patients with rectal cancer.

Comparison of the short-term surgical outcomes of lateral lymph node dissection for low rectal cancer using a robotic-assisted transabdominal approach alone or supported by a transanal approach.

BACKGROUND: Lateral lymph node metastases are a major cause of local recurrence after surgery for advanced low rectal cancer. Lateral lymph node dissection (LLND) may reduce the risk of local recurrence in patients with suspected lateral lymph node metastasis. Recent reports have shown that robotic-assisted LLND can help to reduce the postoperative complication rate, such as urinary disturbance. Furthermore, with the advent of transanal total mesorectal excision, a novel LLND procedure that combines a transabdominal approach with a transanal approach has been reported. This study aimed to clarify the safety and feasibility of robotic-assisted LLND supported by a transanal approach for advanced low rectal cancer. METHODS: Thirty-nine patients diagnosed to have low rectal cancer between June 2019 and May 2023 were retrospectively enrolled and divided according to whether they underwent LLND via a robotic-assisted transabdominal approach alone (transabdominal group, n = 19) or in combination with a transanal approach (2team group, n = 20). The patient characteristics and short-term surgical outcomes were compared between the two groups. RESULTS: The total operation time was significantly shorter in the 2team group than in the transabdominal group (366 min vs. 513 min, P < 0.001), as was the time taken to perform unilateral LLND (64 min vs. 114 min, P < 0.001). Furthermore, there was significantly less intraoperative bleeding in the 2team group (30 mL vs. 80 mL, P = 0.004). There was no significant between-group difference in postoperative complications. The incidence of postoperative urinary disturbance was satisfactory at 5% in both groups. CONCLUSIONS: The operation time for LLND performed by a robotic-assisted transabdominal approach was shortened when supported by a transanal approach. The frequency of postoperative urinary disturbance was low in both groups. Therefore, robotic-assisted abdominal LLND supported by a transanal approach can be considered a promising treatment option for advanced low rectal cancer.

Conversion surgery after successful response to chemotherapy (S-1 + oxaliplatin + nivolumab) in a patient with stage IV gastric cancer with peritoneal metastasis (P1, CY1): a case report.

We here present a case report of a patient with Stage IV gastric cancer with peritoneal metastasis (P1, CY1) who underwent conversion surgery after a successful response to chemotherapy (S-1 + oxaliplatin + nivolumab). The patient was a woman in her 60 s. Her chief complaint was epigastric pain. Upper gastrointestinal endoscopy showed Type 4 advanced carcinoma on the lesser curvature of the gastric body. Biopsy showed Group 5 (poorly differentiated adenocarcinoma) and HER2 was negative. Staging laparoscopy revealed seeding in the round ligament of the liver (P1) and adenocarcinoma cells in ascites (CY1). Ten courses of chemotherapy (S-1 + oxaliplatin + nivolumab) were administered, after which contrast-enhanced computed tomography showed that the primary tumor had shrunk and seeding was no longer detectable. Upper gastrointestinal endoscopy revealed scar-like changes. A second staging laparoscopy revealed that ascites cytology was negative and a biopsy of the round ligament of the liver showed no malignant cells (P0, CY0). Conversion surgery comprising laparoscopic total gastrectomy with D2 lymph node dissection and resection of the round ligament of the liver was performed. The postoperative course was uneventful. Histopathological examination of the resected specimen revealed no tumor cells in the gastric mesentery or the round ligament of the liver. The pathological diagnosis was gastric cancer [M, U, L, Less, Ant, Post, type4, T3(SS), N0, M0 (H0, P0, CY0), ypStage IIA]. Adjuvant chemotherapy (S-1) was commenced. The patient is still alive 7 months later with no evidence of recurrence.

Role of stromal PD-L1 expression in colorectal liver metastasis.

BACKGROUND AND AIM: The outcomes of immune checkpoint blockade for colorectal cancer (CRC) treatment are unsatisfactory. Furthermore, the efficacy of immune checkpoint blockade for liver metastasis of various cancer is poor. Here, we investigated the relationship between stromal programmed death-ligand 1 (PD-L1) expression and the prognosis of patients with colorectal cancer liver metastasis (CRLM). METHODS: The present study enrolled 84 CRLM patients who underwent surgery (R0) for CRC. Immunohistochemistry was performed to analyze stromal PD-L1 expression in CRLM. RESULTS: Stromal PD-L1 was expressed in 52.3% of CRLM samples, which was associated with fewer not optimally resectable metastases (p = 0.04). Stromal PD-L1 also tended to associate with a lower tumor grade (p = 0.08). Stromal PD-L1-positive patients had longer overall survival (p = 0.003). Multivariate analysis identified stromal PD-L1 expression (p = 0.008) and poorer differentiation (p < 0.001) as independent prognostic indicators. Furthermore, stromal PD-L1 expression was correlated to a high number of tumor-infiltrating lymphocytes (TILs). Stromal PD-L1- and low TIL groups had shorter OS than stromal PD-L1 + and high TIL groups (46.6% vs. 81.8%, p = 0.05) Stromal PD-L1-positive patients had longer disease-free survival (DFS) (p = 0.03) and time to surgical failure (p = 0.001). Interestingly, stromal PD-L1 expression was positively related to the desmoplastic subtype (p = 0.0002) and inversely related to the replacement subtype of the histological growth pattern (p = 0.008). CONCLUSIONS: Stromal PD-L1 expression may be a significant prognostic marker for CRLM.

Prognostic impact of frailty after gastrectomy in elderly gastric cancer patients.

BACKGROUND: Frailty plays a crucial role in cancer patients who have received surgery in this recent aging society. We aimed to investigate frailty as a prognostic factor in elderly gastric cancer (GC) patients who underwent curative gastrectomy. METHODS: We analyzed 86 elderly (over 75 years old) GC patients who underwent curative gastrectomy. Patients were assigned to two groups;frailty group (n=29) and no-frailty group (n=57). Clinicopathological values were compared between the two groups. RESULTS: The OS rate of the frailty group was significantly poorer than that of the no-frailty group (5-yr OS rate;frailty group 52.49% vs. no-frailty group 74.87%, p<0.05). Multivariate analysis of the OS showed that frailty tended to be significant prognostic factor (p=0.09). The DFS rate of the frailty group was significantly poorer than that of the no-frailty group (5-yr DFS rate;frailty group 42.30% vs. no-frailty group 71.55%, p<0.05). Multivariate analysis of the DFS showed that frailty tended to be significant prognostic factor (p=0.14). CONCLUSION: We identified the clinical impact of frailty prognostic factor for elderly GC patients who underwent gastrectomy. J. Med. Invest. 70 : 423-429, August, 2023.

Utility of robotic surgery for Siewert type II/III adenocarcinoma of esophagogastric junction: transhiatal robotic versus laparoscopic approach.

BACKGROUND: Robotic surgery (RS) has been rapidly adopted for gastric cancer and adenocarcinoma of the esophagogastric junction (AEG). However, the utility of RS for Siewert type II/III AEG remains unclear. METHODS: Forty-one patients who underwent either transhiatal RS (n = 15) or laparoscopic surgery (LS) (n = 26) for Siewert type II/III AEG were enrolled in this study. The surgical outcomes of the two groups were compared. RESULTS: In the entire cohort, there were no significant intergroup differences in the operative time, blood loss volume, or number of retrieved lymph nodes. The length of the postoperative hospital stay was shorter in the RS group than in the LS group (14.20 ± 7.10 days vs. 18.73 ± 17.82 days, respectively; p = 0.0388). The morbidity rate (Clavien-Dindo grade ≥ 2) was similar between the groups. In the Siewert II cohort, there were no significant intergroup differences in short-term outcomes. In the entire cohort, there was no significant difference between the RS and LS groups in the 3-year overall survival rate (91.67% vs. 91.48%, N.S.) or 3-year disease-free survival rate (91.67% vs. 91.78%, N.S.), respectively. Likewise, in the Siewert type II cohort, there was no significant difference between the RS and LS groups in the 3-year overall survival rate (80.00% vs. 93.33%, N.S.) or 3-year disease-free survival rate (80.00% vs. 94.12%, N.S.), respectively. CONCLUSIONS: Transhiatal RS for Siewert II/III AEG was safe and contributed to similar short-term and long-term outcomes compared with LS.

The application of enhanced recovery after surgery in total gastrectomy: a propensity score-matched analysis.

BACKGROUND: This study aimed to investigate the feasibility and safety of our enhanced recovery after surgery protocol including early oral intake and omitting nasogastric tube (NGT) placement after total gastrectomy. METHODS: We analyzed 182 consecutive patients who underwent total gastrectomy. The clinical pathway was changed in 2015, and patients were divided into 2 groups (conventional group and modified group). Postoperative complications, bowel movement, and postoperative hospital stays were compared in the two groups in all cases and propensity score matching (PSM). RESULTS: Flatus and defecation were significantly earlier in the modified group compared with those in the conventional group (flatus: 2 (1-5) days vs 3 (2-12) days, p = 0.03; defecation: 4 (1-14) days vs 6 (2-12) days p = 0.04). The postoperative hospital stay was 18 (6-90) days in the conventional group and 14 (7-74) days in the modified group (p = 0.009). Days until discharge criteria were met were earlier in the modified group compared with that in the conventional group (10 (7-69) days vs 14 (6-84) days p = 0.01). Overall and severe complications occurred in nine patients (12.6%) and three patients (4.2%) in the conventional group and twelve patients (10.8%) and four patients (3.6%) in the modified group, respectively (p = 0.70 and p = 0.83) in all cases. In PSM, there is no significant difference between the two groups concerning the postoperative complications (overall complication 6 (12.5%) vs 8 (16.7%) p = 0.56, severe complications 1 (2%) vs 2 (4.2%) p = 0.83). CONCLUSIONS: Modified ERAS for total gastrectomy may be feasible and safe.

The Impact of the Pre-operative Neutrophil-lymphocyte Ratio as the Predictive Marker of Post-operative Weight Loss and Improving Diabetes in Sleeve Gastrectomy.

PURPOSE: The aim was to investigate the impact of the neutrophil-lymphocyte ratio (NLR) in sleeve gastrectomy (SG). METHODS: 15 obese patients were enrolled in this study ; mean body weight (BW) 127.5kg ; mean body mass index (BMI) 46.7kg/m2. 10 of these were diabetics who underwent a SG. The impact of the pre-operative NLR on the percentage of excess weight loss (%EWL) and remission of diabetes 1 year post-operative were examined. RESULTS: The %EWL at 1 year post-operative were 46.3%. Improvements were also evident in the diabetes at 1 year post-operative : complete remission (CR) 40%, partial remission (PR) 20% and Improve 40%. Comparing pre-operative NLR in %EWL<50% and ≧50% in 1 year post-operative, <50% was 2.64 and ≧50% was 2.03. The NLR in CR and PR was significantly lower than that in Improve. CONCLUSIONS: The pre-operative NLR may be a predictive marker of weight loss and improving diabetes after SG. J. Med. Invest. 70 : 140-144, February, 2023.

Transanal lateral lymph node dissection with intraoperative hologram support in low rectal cancer.

BACKGROUND: In Japan, the standard treatment for stage II/III advanced low rectal cancer is total mesorectal excision plus lateral lymph node dissection (LLND). There are also recent reports on the use of transanal LLND. However, the transanal anatomy is difficult to understand, and additional support tools are required to improve the surgical safety. The present study examined the utility of holograms with mixed reality as an intraoperative support tool for assessing the complex pelvic anatomy. METHODS: Polygon (stereolithography) files of patients' pelvic organs were created and exported from the SYNAPSE VINCENT imaging system and uploaded into the Holoeyes MD virtual reality software. Three-dimensional images were automatically converted into patient-specific holograms. Each hologram was then installed into a head mount display (HoloLens2), and the surgeons and assistants wore the HoloLens2 when they performed transanal LLND. Twelve digestive surgeons with prior practice in hologram manipulation evaluated the utility of the intraoperative hologram support by means of a questionnaire. RESULTS: Intraoperative hologram support improved the surgical understanding of the lateral lymph node region anatomy. In the questionnaire, 75% of the surgeons answered that the hologram accurately reflected the anatomy, and 92% of the surgeons answered that the anatomy was better understood by simulating the hologram intraoperatively than preoperatively. Moreover, 92% of the surgeons agreed that intraoperative holograms were a useful support tool for improving the surgical safety. CONCLUSIONS: Intraoperative hologram support improved the surgical understanding of the pelvic anatomy for transanal LLND. Intraoperative holograms may represent a next-generation surgical tool for transanal LLND.

Stapler insertion angle toward the esophagus reduces the incidence of early postoperative Roux stasis syndrome after distal gastrectomy in minimally invasive surgery.

BACKGROUND: Roux stasis syndrome (RSS) after Roux-en-Y (RY) reconstruction significantly prolongs the hospital stay and decreases the quality of life. The purpose of the present study was to evaluate the incidence of RSS in patients who underwent distal gastrectomy for gastric cancer and to identify the factors related to the development of RSS after mechanical RY reconstruction in minimally invasive surgery (MIS). METHODS: This study included 134 patients who underwent distal gastrectomy in MIS with mechanical RY anastomosis. RSS was defined as the presence of symptoms such as nausea, vomiting, or abdominal fullness, and the confirmation of delayed gastric emptying on imaging or gastrointestinal fiber testing. Clinical data were checked, including body mass index, operative procedure, age, sex, operative time, blood loss volume, extent of lymph node dissection, final stage, stapler insertion angle, method of entry hole closure. The relationship between the incidence of RSS and these factors was analyzed. RESULTS: RSS occurred in 24 of 134 patients (17.9%). RSS occurred significantly more frequently in patients with D2 lymphadenectomy than in patients with D1 + lymphadenectomy (p = 0.04). All patients underwent side-to-side anastomosis via the antecolic route. The incidence of RSS was significantly greater in patients with a stapler insertion angle toward the greater curvature (n = 20, 22.5%) versus the esophagus (n = 4, 8.9%) (p = 0.04). The multivariate logistic regression model revealed that the stapler insertion angle to the greater curvature is identified as independent risk factor for RSS (OR 3.23, 95%Cl 1.01-10.3, p = 0.04). CONCLUSION: Stapler insertion angle toward the esophagus may reduce the incidence of early postoperative RSS rather than toward the greater curvature.

Visualization of the pelvic nerves using magnetic resonance imaging for rectal cancer surgery.

BACKGROUND: This study evaluated the visualization of the pelvic nerves using magnetic resonance imaging (MRI) combined with computed tomography (CT) to synthesize three-dimensional (3D) reconstruction images of the pelvic organs. METHODS: The CT and MRI scans were performed for patients with rectal cancer who underwent surgery. The out-of-phase image of LAVA-Flex was used to identify the pelvic nerves. The images of the pelvic nerves were extracted from the MRI scans, and those of the arteries and rectum and pelvis were extracted from the CT scans. Each extracted organ image was used to synthesize 3D reconstruction images. RESULTS: The MRI scan allowed adequate visualization of the pelvic splanchnic nerves, inferior hypogastric plexus, and obturator nerves. The comparison of 3D reconstruction images and intraoperative findings showed matched images. CONCLUSION: We visualized the pelvic nerves using MRI and synthesized 3D reconstruction images of the pelvic organs. Preoperative confirmation of the location of the pelvic organs is important to prevent unanticipated injury during rectal cancer surgery.

Role of IDO expression in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy.

BACKGROUND: The role of the immune system in locally advanced rectal cancer (LARC) following preoperative chemoradiotherapy (CRT) has been widely investigated in recent years. This study examined the prognostic significance of indoleamine-pyrrole 2,3-dioxygenase (IDO) expression in patients with LARC who received preoperative CRT. METHODS: Ninety patients with LARC who underwent preoperative CRT and curative resection were enrolled. IDO and programmed death-ligand 1 (PD-L1) expression was evaluated by immunohistochemistry. RESULTS: Clinicopathological factors did not significantly differ between patients with positive or negative IDO expression, excluding the correlation of positive IDO expression with better tumor differentiation (p = 0.02). IDO expression was not associated with pathological response (p = 0.44), but it was associated with PD-L1 expression. The 5-year overall survival (OS) rate was significantly worse in the IDO-positive group than in the IDO-negative group (64.8% vs. 85.4%, p = 0.02). Univariate analysis identified IDO and PD-L1 expression (p = 0.02), surgical procedure (p = 0.01), final pathological stage (p = 0.003), lymph node metastasis (p < 0.001), and lymphatic invasion (p = 0.002) as significant prognostic factors for OS. Multivariate analysis revealed that IDO expression (HR: 7.10, p = 0.0006), surgical procedure (HR: 5.03, p = 0.01), lymph node metastasis (HR: 2.37, p = 0.04) and lymphatic invasion (HR: 4.97, p = 0.01) were independent prognostic indicators. Disease-free survival was not correlated with IDO or PD-L1 expression. CONCLUSIONS: IDO expression in patients with LARC who received preoperative CRT could be a potential prognostic indicator. IDO expression could be a useful marker for specifying individual treatment strategies in LARC.

Short-term outcomes of laparoscopic / robotic gastrectomy compared with open gastrectomy for advanced gastric cancer following chemotherapy.

 Purpose : This study aimed to investigate the short-term outcomes of laparoscopic gastrectomy / robotic gastrectomy after chemotherapy in patients with advanced gastric cancer and compare these outcomes with those of open gastrectomy. Methods : Fifty patients who underwent radical gastrectomy for advanced gastric cancer after chemotherapy between 2007 and 2021 were retrospectively analyzed. The patients were divided into two groups : the laparoscopic gastrectomy / robotic gastrectomy (n = 11) and open gastrectomy (n = 39) groups. The short-term outcomes of these procedures were subsequently examined. Results : The laparoscopic gastrectomy / robotic gastrectomy group had significantly shorter hospital stays and lower intraoperative blood loss than the open gastrectomy group. The overall complication rates were 12.8% (5 of 39 patients) and 0% (0 of 11 patients) in the open gastrectomy and laparoscopic gastrectomy / robotic gastrectomy groups, respectively (P  =  0.1). Conclusions : Laparoscopic gastrectomy / robotic gastrectomy may be a surgical option after chemotherapy for patients with advanced gastric cancer. J. Med. Invest. 69 : 261-265, August, 2022.

Lymph node response to neoadjuvant chemotherapy as an independent prognostic factor in gastric cancer.

Previous studies have revealed the usefulness of neoadjuvant chemotherapy (NAC) followed by surgery for clinical stage III gastric cancer (GC). The tumor volume at the primary tumor site (PT) is sometimes difficult to measure because of the luminal structure; therefore, evaluation of the lymph node (LN) response to NAC may help to more accurately predict survival outcomes. The present study therefore evaluated the LN response to NAC for prediction of survival outcomes in patients with GC. The study involved 160 patients with clinical stage III GC who underwent NAC (n=14) and upfront surgery (n=146). PT and LN responses to NAC were evaluated, various clinicopathological factors were evaluated and Cox proportional hazard regression analyses were performed to determine survival outcomes. Overall survival (OS) and disease-free survival (DFS) were not significantly different between patients who underwent NAC and those who underwent upfront surgery (OS, P=0.71; DFS, P=0.50). However, although there were no significant differences in PT responses, patients classified as LN non-responders to NAC had a significantly worse prognosis compared with patients classified as LN responders in terms of DFS (PT, P=0.93; LN, P<0.01) and OS (PT, P=0.84; LN, P<0.01). Moreover, a higher neutrophil-lymphocyte ratio tended to be associated with poor DFS [univariate: hazard ratio (HR)=4.23, P=0.06; multivariate: HR=6.45, P=0.04]. Finally, an LN response to NAC was significantly better for prediction of recurrence (univariate, HR=7.79, 95% confidence interval=1.16-63.51, P=0.02; multivariate, HR=7.44, P=0.01). Overall, the current study revealed the clinical importance of the LN response to NAC for predicting survival outcomes in patients with GC. These findings highlight the potential clinical impact of optimizing treatment strategies to improve the selection and management of patients.

Computed tomography texture analysis for the prediction of lateral pelvic lymph node metastasis of rectal cancer.

BACKGROUND: This study aimed to investigate the usefulness of computed tomography (CT) texture analysis in the diagnosis of lateral pelvic lymph node (LPLN) metastasis of rectal cancer. METHODS: This was a retrospective cohort study of 45 patients with rectal cancer who underwent surgery with LPLN dissection at Tokushima University Hospital from January 2017 to December 2021. The texture analysis of the LPLNs was performed on preoperative CT images, and 18 parameters were calculated. The correlation between each parameter and pathological LPLN metastasis was evaluated. The texture parameters were compared between pathologically metastasis-positive LPLNs and metastasis-negative LPLNs. RESULTS: A total of 40 LPLNs were extracted from 25 patients by preoperative CT scans. No LPLNs could be identified in the remaining 19 patients. Eight of the 25 patients had pathologically positive LPLN metastasis. Extracted LPLNs were analyzed by the texture analysis. Pathologically metastasis-positive LPLNs had significantly lower mean Hounsfield unit, gray-level co-occurrence matrix (GLCM) energy, and GLCM Entropy_log2 values, and a significantly larger volume than pathologically metastasis-negative LPLNs. Multivariate analysis revealed that the independent predictive factors for LPLN metastasis were volume (a conventional parameter) (odds ratio 7.81, 95% confidence interval 1.42-43.1, p value 0.018) and GLCM Entropy_log2 (a texture parameter) (odds ratio 12.7, 95% confidence interval 1.28-126.0, p value 0.030). The combination of both parameters improved the diagnostic specificity while maintaining the sensitivity compared with each parameter alone. CONCLUSION: Combining the CT texture analysis with conventional diagnostic imaging may increase the accuracy of the diagnosis of LPLN metastasis of rectal cancer.