A Mature Tertiary Lymphoid Structure with a Ki-67-Positive Proliferating Germinal Center Is Associated with a Good Prognosis and High Intratumoral Immune Cell Infiltration in Advanced Colorectal Cancer.

Tertiary lymphoid structures (TLSs) are complex lymphocyte clusters that arise in non-lymphoid tissues due to inflammation or cancer. A mature TLS with proliferating germinal centers is associated with a favorable prognosis in various cancers. However, the effect of TLS maturity on advanced colorectal cancer (CRC) remains unexplored. We analyzed the significance of TLS maturity and tumor Ki-67 expression in surgically resected tumors from 78 patients with pathological T4 CRC. Mature TLS was defined as the organized infiltration of T and B cells with Ki-67-positive proliferating germinal centers. We analyzed the relationship between TLS maturity and intratumoral immune cell infiltration. Mature TLS with germinal center Ki-67 expression was associated with microsatellite instability and improved survival; however, high tumor Ki-67 expression was associated with poor survival in the same cohort. Multivariate analysis identified the absence of mature TLS as an independent predictor of poor post-recurrence overall survival. Intratumoral infiltration of T lymphocytes and macrophages was significantly elevated in tumors with mature TLS compared to those lacking it. High Ki-67 levels and absent mature TLS were identified as poor prognostic factors in advanced CRC. Mature TLS could serve as a promising marker for patients at high-risk of CRC.

Risks and Outcomes of Early Dose Reduction in Adjuvant CAPOX Therapy for Colorectal Cancer.

BACKGROUND/AIM: Adjuvant capecitabine and oxaliplatin (CAPOX) therapy is standard strategy for colorectal cancer with risk of recurrence. Early dose reduction (EDR) of CAPOX therapy is commonly used in real-world practice. However, there is limited evidence regarding the effectiveness of CAPOX for patients who had EDR. Therefore, this study aimed to clarify the risks of EDR and its effect on long-term outcomes and body composition factors. PATIENTS AND METHODS: Patients who received CAPOX therapy after radical surgery for colorectal cancer between June 2013 and December 2021 were included. EDR was defined as dose reduction within four courses of CAPOX therapy. Body composition factors were measured for 1 year following surgery to determine the EDR effects. RESULTS: Eighty-four patients were included; 35 (42%) of them had EDR. The multivariate analysis revealed that underweight [odds ratio (OR)=4.95, 95% confidence interval (CI)=1.13-21.7, p=0.03] was a risk factor for EDR. Relapse-free survival (RFS) was significantly better in the non-EDR group (p=0.01). The 5-year RFS rates for the non-EDR and EDR groups were 88.7% and 65.4%, respectively. The multivariate analysis revealed that age >65 years [hazard ratio (HR)=3.97; 95% CI=1.16-13.62, p=0.03] and EDR (HR=7.62; 95% CI=1.71-33.91, p=0.005) were associated with poorer RFS. The 1-year body composition analysis revealed decreases in all factors in the EDR group. CONCLUSION: Preoperative underweight status was associated with EDR, which resulted in decreased RFS and body composition factors when compared with the non-EDR group. Therefore, avoiding EDR and early nutritional intervention after EDR may improve outcomes.

Prognostic value of a modified­immune scoring system in patients with pathological T4 colorectal cancer.

Tumor-infiltrating immune cells, such as lymphocytes and macrophages, have been associated with tumor aggressiveness, prognosis and treatment response in colorectal cancer (CRC). An immune scoring system, Immunoscore (IS), based on tumor-infiltrating T cells in stage I-III CRC, was used to predict prognosis. An alternative immune scoring signature of immune activation (SIA) reflects the balance between anti- and pro-tumoral immune components. The present study aimed to evaluate the prognostic value of modified IS (mIS) and modified SIA (mSIA) in locally advanced pathological T4 (pT4) CRC, including stage IV CRC. Immunohistochemical staining for immune cell markers, such as CD3 (pan-T cell marker), CD8 (anti-tumoral cytotoxic T cell marker) and CD163 (tumor-supportive macrophage marker), in specimens from patients with radically resected pT4 CRC at stages II-IV was performed. mIS levels in the T4 CRC cohort were not associated with prognosis. However, low mSIA levels were associated with low survival. Furthermore, low mSIA was an independent predictor of recurrence in patients with radically resected pT4 CRC. In patients with CRC who did not receive postoperative adjuvant chemotherapy, low mSIA was a major poor prognostic factor; however, this was not observed in patients receiving adjuvant chemotherapy. Evaluation of the tumor-infiltrating immune cell population could serve as a valuable marker of recurrence and poor prognosis in patients with locally advanced CRC. mSIA assessment after radical CRC resection may be promising for identifying high-risk patients with pT4 CRC who require aggressive adjuvant chemotherapy.

Two-team Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection Using Transanal Approach for Rectal Cancer: A Retrospective Study.

BACKGROUND/AIM: Lateral lymph node dissection is a locally advanced rectal cancer treatment option. Despite its complexities, such as prolonged operative time and increased blood loss, a transanal approach with an abdominal approach may help mitigate these drawbacks. PATIENTS AND METHODS: Between July 2013 and June 2022, 40 patients underwent radical laparoscopic surgery with lateral lymph node dissection for rectal cancer. Among them, 29 and 11 patients underwent total mesorectal excision and lateral lymph node dissection without transanal approach (conventional surgery) and with transanal approach (two-team surgery), respectively. The clinical findings, surgical outcomes, pathology results, and prognoses of conventional and two-team surgeries were retrospectively compared. RESULTS: Compared to conventional surgery, two-team surgery involves increased organ and nerve resections, shorter operation time (286 vs. 548 min, p<0.001), and less blood loss (20 vs. 158 ml, p<0.001). Although postoperative complications were similar between groups, the two-team surgery group had a shorter hospital stay (p=0.006). Pathologically, all patients who underwent two-team surgery had a distal resection margin of at least 20 mm, and no recurrence was observed. With conventional surgery, 63.6% of patients had a 10-19 mm margin, and 36.4% had a margin of ≥20 mm, except for abdominoperineal resection. CONCLUSION: Total mesorectal excision and lateral lymph node dissection with the transanal approach as a two-team surgery are safe and feasible. Two-team surgery resulted in better outcomes than conventional surgery regarding operative time, blood loss, shorter postoperative hospital stay, and adequate distal resection margin.

Association of High LAT1 Expression with Poor Prognosis and Recurrence in Colorectal Cancer Patients Treated with Oxaliplatin-Based Adjuvant Chemotherapy.

The mammalian target of rapamycin (mTOR) is often activated in several cancers. We focused on two mTOR regulatory mechanisms: oxaliplatin-induced mTOR signaling and L-type amino acid transporter 1 (LAT1)-induced mTOR activation. High LAT1 expression in several cancers is associated with mTOR activation and resistance to chemotherapy. However, the significance of LAT1 has not yet been elucidated in colorectal cancer (CRC) patients treated with post-operative adjuvant chemotherapy. Immunohistochemistry was conducted to examine the significance of membrane LAT1 expression in 98 CRC patients who received adjuvant chemotherapy, including oxaliplatin. In vitro analysis was performed using CRC cell lines to determine the effects of LAT1 suppression on proliferation, oxaliplatin sensitivity, and mTOR signaling. LAT1 expression was associated with cancer aggressiveness and poor prognosis in 98 CRC patients treated with adjuvant chemotherapy. We found that positive LAT1 expression correlated with shorter survival in 43 patients treated with the capecitabine-plus-oxaliplatin (CAPOX) regimen. LAT1 suppression in CRC cells inhibited the proliferation potency and oxaliplatin-induced activation of mTOR signaling, and improved oxaliplatin sensitivity. LAT1 evaluation before adjuvant treatment may therefore be a sensitive marker for oxaliplatin-based regimens. Moreover, LAT1 may be a promising target for patients with refractory CRC.

Relationship Between C-reactive Protein-to-albumin Ratio Before and After Bowel Decompression and Prognosis in Acute Malignant Large Bowel Obstruction.

BACKGROUND/AIM: We investigated the relationship between prognosis and the necessity of decompression of large bowel obstruction (LBO) among patients with colorectal cancer admitted to the hospital in an emergency, as well as the correlation between prognosis and improvement in the C-reactive protein-to-albumin ratio (CAR) after decompression. PATIENTS AND METHODS: Seventy-four patients admitted to the hospital between 2013 and 2021 in an emergency due to LBO were included. We examined perioperative clinicopathological factors, bowel decompression type, and prognosis. RESULTS: Of the 74 patients, 24 (32.4%) required bowel decompression. A higher percentage of patients who required bowel decompression had a colorectal obstruction scoring system (CROSS) score 0 (p<0.001) with higher frequency of nutritional disorders (p=0.063) than that in no bowel decompression-requiring patients. The 3-year-disease-free survival was 70.8% in the no decompression-requiring group and 26.9% in the bowel decompression group (p=0.007), while the 3-year-overall survival was 90.8% and 76.5%, respectively (p=0.001). The 3-year-disease-free survival was 49.2% in the improved CAR group and 0.0% in the non-improved CAR group (p=0.024), while the 3-year-overall survival was 91.7% and 56.3%, respectively (p=0.061). CONCLUSION: The necessity of emergency decompression was associated with a poorer prognosis, compared to the no decompression-requiring group. Similarly, a CROSS score of 0 was an independent poor prognostic factor. Among patients who required emergency bowel decompression, those who showed improvement in CAR before and after decompression treatment had a better prognosis than those who did not.

Risk and Protective Factors for Postoperative Complications in Elderly Patients With Colorectal Cancer.

AIM: This study aimed to evaluate perioperative factors, including nutritional status and sarcopenia on short-term postoperative complications, determine the risk factors for postoperative complications, and clarify potential preoperative interventions and optimal surgical procedures to improve short-term outcomes in elderly patients with colorectal cancer (CRC). PATIENTS AND METHODS: This retrospective, single-centre cohort study analysed the factors and short-term postoperative complications of CRC in a cohort of 101 patients aged ≥80 years who underwent radical resection between 2013 and 2020. Nutritional status was evaluated by calculating the controlling nutritional status. RESULTS: The median age was 83 years, and the frequency of sarcopenia was 39.6%. Short-term postoperative complications occurred in 24 patients. Risk factors for short-term postoperative complications in multivariate analysis were sarcopenia combined with nutritional disorders and open surgical approach. CONCLUSION: The status of nutrition and sarcopenia must be considered in order to predict and improve postoperative outcomes. If possible, a laparoscopic approach should be selected to prevent poor postoperative outcomes.

PD-L1 upregulation is associated with activation of the DNA double-strand break repair pathway in patients with colitic cancer.

Ulcerative colitis (UC) is a DNA damage-associated chronic inflammatory disease; the DNA double-strand break (DSB) repair pathway participates in UC-associated dysplasia/colitic cancer carcinogenesis. The DSB/interferon regulatory factor-1 (IRF-1) pathway can induce PD-L1 expression transcriptionally. However, the association of PD-L1/DSB/IRF-1 with sporadic colorectal cancer (SCRC), and UC-associated dysplasia/colitic cancer, remains elusive. Therefore, we investigated the significance of the PD-L1/DSB repair pathway using samples from 17 SCRC and 12 UC patients with rare UC-associated dysplasia/colitic cancer cases by immunohistochemical analysis. We compared PD-L1 expression between patients with SCRC and UC-associated dysplasia/colitic cancer and determined the association between PD-L1 and the CD8+ T-cell/DSB/IRF-1 axis in UC-associated dysplasia/colitic cancer. PD-L1 expression in UC and UC-associated dysplasia/colitic cancer was higher than in normal mucosa or SCRC, and in CD8-positive T lymphocytes in UC-associated dysplasia/colitic cancer than in SCRC. Moreover, PD-L1 upregulation was associated with γH2AX (DSB marker) and IRF-1 upregulation in UC-associated dysplasia/colitic cancer. IRF-1 upregulation was associated with γH2AX upregulation in UC-associated dysplasia/colitic cancer but not in SCRC. Multicolour immunofluorescence staining validated γH2AX/IRF-1/PD-L1 co-expression in colitic cancer tissue sections. Thus, immune cell-induced inflammation might activate the DSB/IRF-1 axis, potentially serving as the primary regulatory mechanism of PD-L1 expression in UC-associated carcinogenesis.

Bowel obstruction due to Chlamydia trachomatis: a case report and review of literature.

BACKGROUND: Chlamydial infection is a difficult-to-diagnose type of sexually transmitted disease that occurs mainly in young people. We report a case of bowel obstruction caused by intrapelvic adhesions formed by chlamydial infection. CASE PRESENTATION: This patient was a 23-year-old woman who had been suffering from acute abdominal pain. She had been previously treated several times for intrapelvic abscesses and had a history of chlamydial infection. Endometriosis was thought to be the cause of her pelvic abscess based on endoscopic findings. Computed tomography demonstrated a small bowel obstruction caused by a pelvic abscess. However, the diagnosis could not be confirmed. She underwent laparoscopic surgery and was diagnosed with bowel obstruction due to adhesion of chlamydial infection based on the intraoperative findings and Chlamydia trachomatis antibody test. She was discharged 5 days after surgery. CONCLUSIONS: It is necessary to consider the possibility of chlamydial infection as a cause for lower abdominal pain and unexplained bowel obstruction in female patients.

Outcomes of surgical treatment in patients with anorectal fistula cancer.

BACKGROUND: No standard treatment for anorectal fistula cancer, such as multidisciplinary therapy, has been established due to the rarity of the disease. Herein, we investigated patients with cancer associated with anorectal fistula who underwent surgery to clarify the clinicopathological characteristics and to propose future perspectives for treatment strategies. CASE PRESENTATION: Seven patients with cancer associated with anorectal fistula who underwent rectal amputation in our institute were analyzed with regard to clinical characteristics, pathological findings, surgical results, and prognosis. Four cases had Crohn's disease as an underlying cause. All seven cases were diagnosed as advanced stage. Preoperative [18F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography/computed tomography (FDG-PET/CT) showed abnormal FDG accumulation in six cases including four mucinous adenocarcinomas. Three cases that received preoperative hyperthermo-chemoradiotherapy achieved pathological R0 resection. Postoperative recurrence was observed in four cases including three with Crohn's disease and one resulting in death. CONCLUSIONS: Anorectal fistula cancer is rare and difficult to be diagnosed at early stages. Mucinous adenocarcinoma associated with anorectal fistula tends to exhibit abnormal FDG accumulation by FDG-PET/CT unlike common colorectal mucinous adenocarcinoma. Preoperative hyperthermo-chemoradiotherapy may be effective in obtaining pathological complete resection.

Retroperitoneal Liposarcoma with Multilocular Cysts.

In this study, we describe a 60-year-old man with a giant retroperitoneal liposarcoma with multilocular cysts. He was admitted to our hospital because of a 5-month history of abdominal distention. Abdominal computed tomography revealed a giant lobulated cystic mass occupying the retroperitoneal space that contained partially solid fat components. Magnetic resonance imaging indicated that this complex mass exhibited a low signal intensity on a T1-weighted image, whereas it exhibited a high and focally intermediate signal intensity on a T2-weighted image. This patient was diagnosed with a mucinous type of retroperitoneal sarcoma, which was then resected. During surgery, the tumor was isolated from the retroperitoneum and other organs, but the detachment was required only because of fixation around the left external iliac artery. The histological diagnosis was a well-differentiated liposarcoma with multilocular cysts that contained old bloody, serous, and mucinous fluids, which are a rare phenomenon in liposarcoma. This case indicates that retroperitoneal liposarcoma should also be considered as a differential diagnosis of retroperitoneal cystic mass.

Paget's disease derived in situ from reserve cell hyperplasia, squamous metaplasia, and squamous cell carcinoma of the esophagogastric junction: a case report.

BACKGROUND: Extramammary Paget's disease (EMPD) of the esophagus is a rare tumor, with most cases originating from invasive adenocarcinoma of the esophagus. Pure esophageal Paget's disease, in which no underlying invasive carcinoma component is present, is extremely rare. In this report, we describe a case of EMPD of the esophagogastric junction with no evidence of invasive carcinoma. CASE PRESENTATION: An 81-year-old Japanese woman with a 2-week history of abdominal distension presented to our hospital for assessment. Endoscopic examination revealed a mild elevated granular lesion, with a slightly depressed irregular mucosa, in the distal esophagus, with EMPD confirmed by biopsy. Thoracoscopic esophagectomy with lymph node dissection was performed, with Paget cells observed on microscopic examination in the lower part of the esophageal epithelium. Only a few Paget cells stained positively for PAS/Alcian blue. Immunohistochemically, negative staining for CK5 and p63 were identified in the Paget cells, with positive staining for CK7. Furthermore, an intraepithelial squamous cell carcinoma, with squamous metaplasia and reserve cell hyperplasia, was observed in the gastric mucosa of the esophagogastric junction, adjacent to the Paget cells. CONCLUSIONS: EMPD of the esophagus is a rare disease. We report a case of EMPD that was probably derived from a gastric squamous cell carcinoma, with squamous cell metaplasia and reserve cell hyperplasia, in the esophagogastric junction, which, to our knowledge, is the first report of this type of EMPD in the clinical literature.

[Low-Dose and Interval Administration of Imatinib in a Patient with Liver Metastasis of the Gastrointestinal Stromal Tumor of the Stomach - A Case Report].

A 69-year-old woman underwent proximal gastrectomy with distal pancreatectomy and splenectomy for a gastrointestinal stromal tumor of the stomach.Adjuvant imatinib was administered for a year.Two years after resection of the tumor, liver metastasis in S8 was detected.Therefore, imatinib was re-administered at 300mg/day.After a year of re-administration, the patient suffered muscle cramps in the hands, and therefore imatinib was administered with intervals, such as 4 weeks administration and 4 weeks rest.Re -administration of imatinib was effective and her liver metastasis decreased in size.It was not detected with CT after 1 year and 4 months and remained in complete response(CR)for 3 years and 8 months.After she suffered a brain infarction, imatinib administration was stopped for 4 months.Consequently, the liver metastasis was detectable in S8 again.This clinical course suggested that low-dose and interval administration of imatinib is effective in the treat- ment of GIST.