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.

Alpha-fetoprotein producing gastric cancer with divergent differentiation: Report of a rare case with review of literature.

ABSTRACT: Alpha-fetoprotein-producing gastric cancer is a rare variant of gastric adenocarcinoma. This tumor is likely to be misdiagnosed, particularly in patients with liver metastasis. This rare subgroup of gastric carcinoma may show divergent differentiation on histology and may pose a diagnostic challenge to the pathologist. They have an aggressive course with a dismal prognosis.

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.

Immunohistochemical expression of perforin in adult systemic lupus erythematosus associated macrophage activation syndrome: Clinicohematological correlation and literature review.

OBJECTIVE: To study the bone marrow (BM) immunohistomorphological characteristics in adult systemic lupus erythematosus (SLE) associated macrophage activation syndrome (SLE-MAS). MATERIALS AND METHODS: Immunohistochemical (IHC) expression of CD3, CD8, perforin (PFN), and CD163 was studied on BM trephine biopsies from 30 cytopenic adult SLE cases (male: female = 1:5, age; 24 years, range; 19-32) and compared them with ten age matched controls. Clinicopathological parameters were compared among the cases likely (L) or unlikely (U) to have MAS using probability scoring criteria. The best cut off laboratory parameters to discriminate between the two were obtained through receiver operator curve (ROC) analysis. RESULTS: MAS occurred in 12/30 (40%) cases and was more commonly associated with prior immunosuppressive therapy (p = .07), ≥ 3 system involvement (p = .09), lower fibrinogen (p < .01), increased triglyceride (p = .002), increased BM hemophagocytosis (p = .002), and higher MAS score [185 (176-203) vs. 105 (77-119), p < .01] than MAS-U subgroup. Although PFN+CD8+ T lymphocytes significantly decreased among cases than controls (p < .05), it was comparable between MAS-L and MAS-U subgroups. Fibrinogen (< 2.4 g/L, AUC; 0.93, p < .01), hemophagocytosis score (> 1.5, AUC; 0.71, p = .03), and an MAS probability score of ≥ 164 (AUC; 1, p < .01) discriminated MAS from those without MAS. CONCLUSION: We noted a decrease in perforin mediated CD8 + T cell cytotoxicity in SLE. Immunohistochemical demonstration of the same along with histiocytic hemophagocytosis on BM biopsy may be useful adjunct in early diagnosis and management of MAS in SLE.

Inclusion of Perineural Invasion with AJCC-TNM Staging: Outcomes from a South Asian Cohort of Curatively Treated Gastric Cancer Patients.

BACKGROUND: The incidence of perineural invasion (PNI) in patients with gastric cancer (GC) is high, and patients with PNI positive disease have a poor prognosis compared to PNI-negative disease. The present study aims to study the incidence and evaluate the impact of PNI on the survival outcome of a cohort of South Asian GC patients. MATERIAL AND METHODS: All consecutive patients undergoing curative gastrectomy were included in the study. The incidence of PNI and correlation with different clinico-pathological features and overall survival was performed. RESULTS: A total of 59.54% had PNI-positive disease and the median OS of PNI + ve patients was 29.3 months, while it was not reached in PNI-ve patients. The PNI positivity was a significant prognostic factor for overall survival both on univariate and multivariate analysis. On TNM-PNI staging, those with TNM stage I/II patients with PNI + ve disease had similar OS to all stage III patients (p = 0.835) and were worse than that of PNI-ve patients (p < 0.05). CONCLUSION: The incidence of PNI in gastric cancer is high. The inclusion of PNI with AJCC-TNM staging may better stratify prognostic staging in curatively treated gastric cancer patients.

Elevated expression of cholesterol transporter LRP-1 is crucially implicated in the pathobiology of glioblastoma.

Glioblastoma (GBM) is the most common primary malignant brain tumor with a grave prognosis. The present study evaluated the expression of Cholesterol transporter [importer -Lipoprotein Receptor-related Protein-1 (LRP-1) and exporter -ATP-binding cassette transporters-1 (ABCA-1)] in GBM and their implications in tumor-biology, clinical outcome and therapeutic potentials. The mRNA and protein expression was assessed by qRT-PCR and immunohistochemistry, respectively, in 85 GBMs. For comparison, 25 lower-grade astrocytomas (IDH-mutant, grade-2/3) [LGA] 16 cases of high-grade astrocytomas (IDH-mutant, grade-4) [HGA] were also evaluated. In-vitro analysis was performed on U87MG and LN229 glioma cell line. The expression of LRP-1 (mRNA and protein) was significantly higher in GBM than LGA, HGA and normal brain (NB) [p-values 0.007, 0.003 and <0.001 for mRNA; 0.024, <0.001 and <0.001 for immunohistochemistry]. Majority of the GBMs (82.4%) showed strong immunoreactivity for LRP-1, and all tumor cases were positive while the normal brain was negative. LRP-1 immunoreactivity positively correlated with the MIB-1 labeling index (p-value-0.013). LRP-1 knockdown in-vitro was associated with decreased cell survival, proliferation, migration, invasion, and increased apoptosis. Similar effect was also demonstrated by Receptor Associated Protein (RAP), a LRP-1 inhibitory drug. The silencing of LRP-1 was also associated with decreased cholesterol level. The ABCA-1 expression was higher in GBM than LGA and NB (p-value 0.011 and <0.001), however there was no significant association with other parameters. LRP-1 showed a positive correlation with ABCA-1 and associated with decreased expression with LRP-1 knock-down in-vitro. The expression of LRP-1 and ABCA-1 didn't correlate with overall survival in GBMs. Hence, LRP-1 is crucial for the tumor cells' survival and aggressive biological behavior which is maintain through the regulation of high intracellular cholesterol import. Its expression is significantly higher in GBMs and also implicated in the regulation of ABCA-1 expression. Considering its immune-positivity only in the neoplastic cell and strong positivity in GBM it may be a useful adjunct to the diagnosis. For the first time, the present study emphasized its role as a potential therapeutic target in the form of RAP which is presently being used in other neurological diseases under clinical trials.

Malignant gastrointestinal neuroectodermal tumor: A case-based review of literature.

Malignant gastrointestinal (GI) neuroectodermal tumor is an extremely rare entity that was first described by Zambrano et al. in 2003 as "clear cell sarcoma (CCS)-like tumor of the GI tract." It shares some of the histopathological features of CCS but lacks the immunohistochemical (IHC) reactivity for melanocytic markers. Most mesenchymal neoplasms of the GI tract belong to the category of GI stromal tumors and are characterized by the IHC expression of c-KIT. In cases, without detectable KIT receptor expression, several differential diagnoses have to be taken into consideration. In this article, we describe such a case and present a review of all the reported cases till date. We also present the current available knowledge on its pathology and molecular genetics along with the limitations in its diagnosis. Here, we report a case of a 32-year-old man with a tumor of the small bowel composed of polygonal tumor cells arranged in solid nests, alveolar pattern, and pseudopapillary and admixed with numerous osteoclast-like multinucleated giant cells. Immunohistochemically, the tumor cells strongly expressed S-100 protein only. HMB-45, melan-A, CD117, cytokeratin, desmin, smooth muscle actin, and CD-34 were absent. Ki-67 index was 15%. The diagnosis was further confirmed by fluorescence in situ hybridization (FISH) demonstrating the presence of EWSR1 (22q12) translocation. A final diagnosis of malignant gastroneuroectodermal tumor was rendered. The patient is disease-free for 20 months of postsurgery. The diagnosis of this entity should be considered in the presence of S-100-positivity and multinucleated osteoclastic giant cells and the absence of melanocytic differentiation in a tumor arising from GI tract. Further confirmation can be done by performing FISH analysis.

Hepatic Follicular Dendritic Cell Sarcoma with Epithelioid Morphology: Histopathologist's Perspective.

Follicular dendritic cell (FDC) sarcoma is an uncommon tumor of the liver with only 30 previous cases reported in the English literature. Histopathological examination is the gold standard for the diagnosis of FDC sarcoma although the diagnosis is often missed because of its rarity. It usually presents with spindle-cell morphology although epithelioid/biphasic morphology is also well-known. This morphological variation can also pose a diagnostic challenge. We discuss a case of unresectable hepatic FDC sarcoma in an adult male who was diagnosed in core biopsy. We highlight the relevant histomorphological differentials and diagnostic approaches to FDC sarcoma in this anecdote.

Strongyloides Hyperinfection Syndrome in Dermatology in-Patients: A Case Series.

Strongyloides stercoralis is a common intestinal pathogen, which often causes disseminated infection in patients on long term immunosuppressive therapy. The features of this syndrome range from subtle abdominal discomfort to fatal infection. Many of the immunologically mediated dermatological conditions need prolonged treatment with Immunosuppressants. Hence there is increased risk of this infestation. In dermatology in-patients, strongyloides stercoralis hyperinfection can be confused with a number of conditions, such as steroid-induced gastritis, corticosteroid withdrawal, electrolyte imbalance, lepra reactions, and erythrodermic enteropathy. In a country like India, where barefoot walking is still prevalent, this condition has been reported less often. We report a series of five patients who were diagnosed with strongyloides hyperinfection syndrome during their admission in the dermatology department during the last year. This case series aims at creating awareness among the dermatologists, so that, this, potentially fatal but easily preventable and treatable condition, can be managed properly.

Expression of CD56 is Not Limited to Biliary Atresia and Correlates with the Degree of Fibrosis in Pediatric Cholestatic Diseases.

BACKGROUNDS AND AIMS: CD56 immunostain is used as an adjunct to aid in the preoperative diagnosis of biliary atresia (BA) by liver biopsy. We aimed to study the expression of CD56 in different pediatric cholestatic diseases thereby evaluating its utility in the diagnosis of BA. METHODS: We performed immunohistochemistry for CD56 on 35 cases of pediatric cholestatic diseases and five age-matched controls. CD56 expression was assessed by a multiplication score (percentage positivity x intensity) in the biliary epithelium. RESULTS: The multiplication score between BA and choledochal cyst was not significantly different. High scores were also encountered in other cholestatic disorders. The score showed a significant negative association with serum albumin and a significant positive correlation with the serum ALT level. Very significant positive correlation between the score and portal fibrosis was obtained. CONCLUSION: CD56 expression is an infidel marker for the histological diagnosis of BA and rather provides a clue to the disease status in pediatric cholestatic diseases.

The Clinico-histopathological Spectrum of Tumors and Tumor-Like Lesions in Adult Intussusception.

BACKGROUND: Intussusception is an uncommon cause of intestinal obstruction in adults. The etiology of this disease differs from the children. Thus, its management depends on the possible etiology and is different from pediatric cases. AIMS: We aimed to study the clinico-histopathological spectrum of the tumors and tumor-like lesions in the intussusception in adults. MATERIAL AND METHODS: A retrospective review of the adult (> 18 years) intussusception cases was performed. The clinical data and follow-up were obtained. The histopathology was reviewed along with the special stains and immunohistochemistry for ascertaining a histopathological diagnosis. RESULTS: Fifteen cases of adult intussusception were identified from 107 resected specimens of adult intestinal obstruction. The mean age was 44.5 years with a male/female ratio of 1.1:1. A definitive pathology could be ascertained in 80% of the cases (n = 12/15). Eight cases had benign non-neoplastic etiology (53.3%) (33.3% tumor-like lesions) while seven cases (46.7%) had neoplastic etiology (20% benign neoplastic; 26.7% malignant neoplastic). All cases of colonic or enterocolic intussusceptions were associated with neoplasia whereas 90% of the enteric intussusceptions occurred due to benign non-neoplastic causes.  CONCLUSIONS: Non-neoplastic causes are predominant in the enteric intussusceptions while neoplastic causes are more commonly associated with colonic or enterocolic intussusceptions. The post-operative histopathological examination concludes on the adequacy of the index surgery or the provision of further management if required.

Elevated Expression of DNA Methyltransferases and Enhancer of Zeste Homolog 2 in Helicobacter pylori - Gastritis and Gastric Carcinoma.

AIM: The aim of this study was to study the role of key epigenetic regulators pertaining to DNA methylation and histone-modification systems in Helicobacter pylori (HP)-associated gastritis and gastric carcinogenesis. METHODS: The expression of DNA methyltransferase (DNMT-1, 3A, and 3B) and the catalytic subunit of polycomb repressive complex-2 (enhancer of zeste homolog 2 [EZH2]) in gastric carcinomas (n = 104), mucosa adjacent to carcinoma (n = 104), HP-associated gastritis (n = 95), and histologically normal mucosa (n = 31) was assessed by immunohistochemistry and qRT-PCR. RESULTS: The expression of all 3 DNMTs and EZH2 was significantly higher in HP-associated gastritis and carcinoma cases than in those with adjacent and normal mucosa. The expression of DNMT-1 and 3B was maximum in HP-associated gastritis. DNMT-3A showed higher expression in carcinoma-adjacent mucosa than in normal mucosa. Interestingly, the expression of EZH2 was higher in cases of HP-associated gastritis with metaplasia than in those without metaplasia and also in cases of intestinal type of adenocarcinoma. Significant positive correlation of EZH2 was identified with DNMT-1, DNMT-3A, and DNMT-3B. However, none of these markers was associated with survival outcome. CONCLUSION: This study establishes an important role of the key epigenetic regulators in the pathogenesis of both HP-associated gastritis and gastric carcinoma. Higher expression of all the epigenetic markers in the gastritis and their persistence in the carcinoma point toward their implications in HP-driven gastric carcinogenesis. Further, an inter-relation between the 2 arms of epigenetics, namely, DNA methylation and histone-modification in the pathogenesis of gastric carcinoma, is also documented. Given the reversibility of epigenetic phenomenon, these molecules may be of important therapeutic use.