PD-L1 Expression in Colorectal Carcinoma Correlates with the Immune Microenvironment.

INTRODUCTION/BACKGROUND: Colorectal carcinoma (CRC) is a common malignancy, with its diverse clinical, pathological, and molecular features. The immune microenvironment of a tumor comprises of interplay between various cells and molecules, and has a significant role in deciding the tumor behavior and overall prognosis. PD-L1 (programmed cell death ligand-1) has been implicated in the regulation of the tumor immune microenvironment (TIME). There is limited data regarding the correlation of PD-L1 expression with immune cell profile in CRCs, especially in the Indian setting. The study aimed to assess the PD-L1 expression in CRC tumor cells and its association with TIME, mismatch repair (MMR), and various other clinicopathological parameters. METHODS: This is a hospital-based, cross-sectional observational study. PD-L1 expression was assessed at the protein level by immunohistochemistry and mRNA level by qRT-PCR. Immune cell markers (CD4, CD8, CD20, FOXP3, and CD163) were interpreted using the ImageJ Fiji platform. RESULTS: Of the 104 cases, 21% were PD-L1 positive and were more common in right-sided CRCs. PD-L1 positive cases showed significantly higher concentrations of all T-cell subsets (CD4+ , CD8+ , and FOXP3+), CD20+ B-cells, and CD163+ macrophages were noted. No statistical significance was seen between PD-L1 expression with clinical profile, pathological subtype, grade or stage, mismatch repair status (proficient vs deficient), and survival. CONCLUSIONS: The present study showed a relatively lower frequency of PD-L1 in CRC from the Eastern Indian cohort. The immune cell concentration in the present study was calculated using image analysis-based objectivised methods. Significant correlation of PD-L1 expression in tumor cells with the tumor-infiltrating immune cells indicated its crucial role in the pathobiology of CRC especially by regulating the TIME. Considering the therapeutic implication of PD-L1 in various malignancies, it may be one of the crucial therapeutic targets in a proportion of cases.

Effect of Preoperative Body Mass Index on Postoperative and Long-Term Outcomes in an East Indian Gastric Cancer Cohort.

BACKGROUND: Gastric cancer is a global health concern with varying clinical outcomes. This study aims to investigate the influence of preoperative Body Mass Index (BMI) on survival in patients who underwent curative resection for gastric cancer in Eastern India. METHODS: Data from a prospectively maintained Surgical Oncology database were analysed for patients who underwent curative resection for primary gastric adenocarcinoma between May 2016 and March 2022. Patients with incomplete data were excluded. Preoperative BMI was categorised into three groups: Underweight (< 18.5 kg/m2), Normal (18.5-22.9 kg/m2), and Overweight/Obese (=23 kg/m2). Clinicopathological details, short-term outcomes, and long-term oncological outcomes were assessed. Statistical analysis included survival estimates, Cox proportional hazard models, and subgroup analysis. RESULT: Of 162 patients, 145 met the inclusion criteria. Patients were predominantly male (68%) with middle or lower socioeconomic status. No significant differences amongst BMI groups were observed in performance score, tumour grade, clinical stage, or short-term outcomes. Postoperative complications and 30-day mortality were similar. However, underweight patients had poorer 4-year disease-free survival (DFS) compared to overweight/obese patients (14.3% vs. 39.7%, p = 0.03). Overweight/obese patients showed significantly better 4-year overall survival (OS) than underweight patients (47.8% vs. 20.4%, p = 0.03). CONCLUSIONS: In Eastern Indian gastric cancer patients undergoing curative resection, preoperative higher BMI (overweight/obese) was associated with better long-term survival. Understanding these findings could guide tailored interventions to improve outcomes in this population.

Effectiveness and safety of Shankhaprakshalana-a yogic technique-in bowel preparation for colonoscopy: A retrospective study.

INTRODUCTION: Shankhaprakshalana (SP) is a yogic method aiming to cleanse the bowel. It involves the use of warm saline water and a combination of five asanas. This study was designed to assess the effectiveness and safety of bowel preparation by SP. METHODS: This is a retrospective observational study of prospectively collected data. Patients planned for colonoscopy were screened and enrolled to undergo bowel preparation by SP on the day of the colonoscopy. Patients having comorbid conditions, poor performance status, suspected or previously diagnosed intestinal stricture and past history of major abdominal surgery and those unable to perform asanas of SP were excluded. A low-fiber diet was advised for one day before the colonoscopy. Patients were advised to drink 400 mL of lukewarm saline water followed by five asanas (exercises) of SP, each done eight times dynamically and sequentially. After completing six such cycles, patients underwent colonoscopy. Boston Bowel Preparation Scale (BBPS) score was used to assess the quality of bowel preparation. RESULTS: Total 238 patients were included. The major indications for colonoscopy were abdominal pain (35.3%), hematochezia (23.9%), diarrhea (20.2%), constipation (10.9%) and anemia (9.7%). The mean age was 37.7 (± 12) years. The mean BBPS was 8 (± 1.2). Bowel preparation was inadequate (BBPS < 6) in only two patients. Mean segmental BBPS for the three segments of the colon (right, transverse and left) was 2.6 (± 0.5), 2.7 (± 0.4) and 2.6 (± 0.7), respectively. Minor adverse events (nausea, abdominal pain, vomiting, giddiness and bloating) were noted in 10 participants (4.2%), which did not require hospitalization. Bowel preparation was completed in 133 (± 35) minutes. CONCLUSION: Shankhaprakshalana is an effective and safe method to achieve adequate bowel preparation before colonoscopy. Since this is a single-center and retrospective study, future multi-centric, prospective studies comparing it with the standard bowel preparation regimens are warranted.

Natural Killer Cell Enteropathy With Extraintestinal Involvement: Presenting as Symptomatic Anemia.

Natural killer (NK) cell enteropathy is a newly described disease entity with benign behavior and an indolent clinical course, characterized by the atypical proliferation of NK cells throughout the gastrointestinal tract. The exact etiology is unknown. It closely mimics NK/T-cell lymphoma. We describe this atypical entity in a young adult man presenting with vague upper gastrointestinal symptoms and anemia requiring blood transfusion. The response to budesonide therapy points toward a possible low-grade autoimmune process. Considering the benign behavior and self-limiting course, recognizing this entity is essential to avoid over the investigation and aggressive, inappropriate therapy.

Diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration of tubercular lymphadenitis using combination of cytology and Gene Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) genes.

Diagnostic yield of an automated molecular test, Gene Xpert Mycobacterium tuberculosis/rifampicin (MTB/RIF), was evaluated in this study to simultaneously detect the MTB gene and resistance to rifampicin (RIF) on cytology samples acquired via endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNAC) in suspected tubercular lymphadenitis. Microscopy, cytology, Gene Xpert MTB/RIF assay data on Acid-fast bacillus (AFB), and traditional culture of lymph nodes were retrospectively analyzed. Thirty-one patients (median age 33.5 years, inter-quartile range [IQR] 21-66, 18, 58% female) presented with fever (28, 90%), dysphagia (2, 7%), and recurrent subacute intestinal obstruction (1, 3%). Gene Xpert showed higher sensitivity (30, 97%) compared to the other tests: cytology (23, 77%; odds ratio [OR] 8.8, 95% confidence interval [CI] 1.0-76.9; p = 0.05), AFB smears (12, 39%; OR 50, 95% CI 5.9-420.4; p = 0.00001), and conventional culture (4, 13%; OR 188.5, 95% CI 19.7-1796.3; p = 0.0000). We conclude that Gene Xpert MTB/RIF test on EUS-guided FNAC samples is very useful to diagnose tubercular lymphadenitis.

Laparoscopic colectomy in idiopathic colonic varices: a safe endeavour.

A 32-year-old man presented to the emergency department with recurrent episodes of haematochezia and haemodynamic instability. He had no complaints of alteration in bowel habits or mucus discharge in the stool. He was a non-smoker and does not consume alcohol. After stabilising the patient, clinical evaluation and investigations with gastrointestinal endoscopy revealed dilated and tortuous submucosal veins involving the entire colon excepting the distal sigmoid. CT angiography and Doppler ultrasonography revealed normal patency and flow in the mesenteric vessels as well as hepatic, portal vein and inferior vena cava. With the exclusion of the secondary causes, we made the diagnosis of the rare entity of idiopathic colonic varices. He underwent a laparoscopic colectomy with ileorectal anastomosis, without any additional technical challenges intra-op and had an uneventful postoperative recovery. Idiopathic colonic varices can be a differential diagnosis of gastrointestinal bleeding and one can safely proceed with laparoscopic colectomy.

Primary Extragastrointestinal Stromal Tumours in the Hepatobiliary Tree and Telocytes.

The first decade of the twenty-first century witnessed the presence and light microscopic, immunophenotypic, and ultrastructural characterization of interstitial Cajal-like cells (coined as 'telocytes') in virtually every extragastrointestinal site of the human body by Laurentiu M. Popescu and his co-workers. Not surprisingly, stromal tumours, immunophenotypically similar to that of telocytes [CD117 (c-KIT) +/CD34 +], have also been sporadically reported outside the tubular gut (so-called extragastrointestinal stromal tumours, EGISTs), including the gall bladder, liver, and pancreas. A meticulous literature search from January 2000 to November 2015 have found 9 such case reports of EGISTs in the gall bladder, 16 in the liver, and 31 occurring in the pancreas. The site wise mean age at presentation for these tumours were reported to be 62.2 ± 16.6, 50.9 ± 20.1, and 55.3 ± 14.3 years, respectively. Six of nine EGISTs in the gall bladder were associated with gallstones. On pathological evaluation, these tumours exhibited prominent spindled cell morphology and consistent expression of CD117/c-KIT and CD34 on immunohistochemistry and variable expression of vimentin and α-smooth muscle actin. The biological behaviour of hepatic and pancreatic lesions was favourable compared to that in the gall bladder, following definitive surgery with or without imatinib therapy. While the exact pathophysiologic role played by telocytes in various organs is yet to be fully elucidated, there seems to be a direct link between these enigmatic stromal cells and pathogenesis of gallstones and origin of EGISTs, and a hope for targeted therapies. Furthermore, the possible role of telocytes in hepatic regeneration and liver fibrosis opens a new dimension for futuristic research.

Diagnostic dilemma: Kikuchi's disease or tuberculosis?

Any patient from a tuberculosis (TB) endemic area such as India with classical clinical features of fever, weight loss and lymphadenopathy, making a diagnosis of Kikuchi's disease (KD) prior to waiting for the 6-week culture is not appropriate. KD or histiocytic necrotising lymphadenitis is a rare self-limiting cervical lymphadenitis, often a diagnosis of exclusion. One needs to exclude TB, sarcodosis, lymphoma and autoimmune diseases to make such a diagnosis. The patient here with classical clinical presentation of TB with lymph node biopsy mimicking KD (biopsy and immunohistochemistry) posed a big diagnostic dilemma. However, culture of the biopsied lymphatic tissue was confirmed to be mycobacterium TB after the 6th week of incubation. The patient was treated with antitubercular drugs initially, and later, steroid was added in view of his persistent symptoms and he responded. One should wait for the tissue culture report to confirm or exclude the diagnosis of TB. Exclusion should not be based only on laboratory criteria. Histopathogically, TB can mimic any other granulomatous disorder.

Waldenstrom macroglobulinemia presenting with pancreatic mass: a case report and review of literature.

CONTEXT: Waldenstrom macroglobulinemia is a rare lymphoplasmacytic lymphoma characterized by a wide range of clinical presentations related to direct tumor infiltration and the production of IgM. Most commonly it presents with cytopenia, hepatosplenomegaly, lymphadenopathy, constitutional symptoms, and hyperviscosity syndrome. CASE REPORT: We report a case of Waldenstrom macroglobulinemia in an 60-year-old female who initially presented with intermittent abdominal pain. The patient had no peripheral lymphadenopathy. On extensive investigation she was found to have pancreatic mass. The diagnosis of Waldenstrom macroglobulinemia was established after cytomorphology and immunohistochemical analysis of the patient's bone marrow revealed the presence of a lymphoid/lymphoplasmacytoid-like bone marrow infiltrate along with an elevated serum IgM level. The patient responded both clinically and serologically to chemotherapy. This case is unusual because the patient lacked all common clinical features of Waldenstrom macroglobulinemia with exception of anemia. CONCLUSION: To our knowledge this is the first report of a patient with Waldenstrom macroglobulinemia presenting with a pancreatic mass adding to the spectrum of clinical presentations seen in this disease. This adds to the wide variety of gastrointestinal related clinical presentations of Waldenstrom macroglobulinemia and points to the need for considering Waldenstrom macroglobulinemia along with other lymphoid neoplasms in the differential diagnosis of pancreatic lesions.