Differential expression of CK7, CK20, CDX2 in intestinal and pancreatobiliary types of preriampullary carcinoma

Context: Incidence of periampullary carcinoma is low, approximately 0.5–2% of all gastrointestinal malignancies. Histologic subtyping has a prognostic bearing. The purpose of this study is to differentiate periampullary carcinomas based on immunohistochemistry (IHC) by using cytokeratin 7 (CK7), cytokeratin 20 (CK20), caudal type homeobox 2 (CDX2). Aims: To analyze the usefulness of IHC as single/panel of markers that included CK7, CK20, and CDX2. Settings and Design: This was a prospective study done from January 2017 to September 2018. Subjects and Methods: A total 50 pancreaticoduodenectomy specimens were evaluated and classified as intestinal (INT) and pancreaticobiliary (PB) types based on their morphological and immunohistochemical features, respectively. The morphologic subtypes, expression of IHC markers were correlated with different histologic parameters. Statistical Analysis: Chi-square test was used to study the association between different IHC markers with histologic parameters. Probability (P) values <0.05 were regarded as statistically significant. Results: The expression of CK7, CK20, CDX2 were studied in 50 cases to classify them as INT and pancreatobiliary subtypes. CK7 has high sensitivity (88.2%), CDX2 has high specificity (96.4%), CK20+/CDX2+ has both high sensitivity (94.2 percent) and specificity (89.2 percent) in differentiating INT from pancreatobiliary subtypes. The morphologic subtypes showed correlation with two variables (tumor grade, pathologic T stage). CK20 and CK20/CDX2 expression showed a positive correlation with tumor grade, pathologic T staging, and lymphovascular invasion. Conclusions: In conclusion, morphological classification can significantly discriminate histologic types, IHC plays a moderate role. However, the combined expression of CK20 and CDX2 is helpful in subtyping.

Primary extragastrointestinal stromal tumors: A clinicopathological and immunohistochemical study-A tertiary care center experience.

Background: Extra gastrointestinal stromal tumors (EGIST) are uncommon compared to their gastrointestinal counterparts. EGISTs involve omentum, mesentery, retroperitoneum, pancreas, and pelvis. Materials and Methods: Ten EGISTs were analyzed in this study from January 1995 to November 2011. They were analyzed with respect to clinical features, imageological, histopathological, and immunohistochemical findings. The immunohistochemical stains used were Smooth muscle actin (SMA), Desmin, S-100 protein, CD34 and CD-117. Results: There was slight female preponderance with wide age range. Four of the tumors were in retroperitoneum, three in mesentery, and two in omentum and one in pelvis. Histopathologically majority were spindle cell tumors. Immunohistochemically CD117 was consistently positive followed by CD34. Smooth muscle actin was positive in eight cases, S-100 protein and desmin were positive in two cases each. Conclusion: EGISTs are rare and should be considered in the differential diagnosis of the mesenchymal tumors and immunohistochemistry helps to confirm the diagnosis. Further study with better follow-up is desired to characterize these uncommon tumors.

Aetiology of peripheral lymphadenopathy in adults: analysis of 1724 cases seen at a tertiary care teaching hospital in southern India.

BACKGROUND: In patients presenting with peripheral lymphadenopathy, excision biopsy of the most accessible lymph node provides material to establish an early diagnosis, and is important in the management of these patients. METHODS: A retrospective study was done of 1724 lymph node biopsy specimens obtained from adult patients and submitted for histopathological examination over a 12-year period. RESULTS: About one-third (n = 614; 35.6%) of these patients had non-specific lymphadenitis. This included a heterogeneous group of disorders comprising benign follicular hyperplasia, reactive hyperplasia, marked follicular hyperplasia and reactive sinus histiocytosis. Tuberculosis lymphadenitis (n = 540; 31.3%) and malignancy (n = 447; 25.9%) were the other common causes. Of the 540 patients with tuberculosis lymphadenitis, the human immunodeficiency virus (HIV) status was tested in 424 (78.5%) patients; of these, 34 patients (8%) were HIV-seropositive. Epithelioid granulomas with caseation necrosis were more frequently seen in HIV-seronegative patients compared with HIV-seropositive ones (chi2 = 54.66; p < 0.001 ). In HIV-seropositive patients, multiple sites of lymph node involvement (chi2 = 40.597; p < 0.001), suppurative type with adjacent necrosis and panniculitis (chi2 = 68.128; p < 0.001), and non-reactive histological types (chi2 = 109.234; p < 0.001) were more commonly seen compared with HIV-seronegative patients. Kikuchi-Fujimoto disease (n = 36), Kimura disease (n = 7), Rosai-Dorfman disease (n = 6), were rare aetiological causes that have been infrequently reported from India. CONCLUSION: Awareness of the characteristic histopathological findings and uncommon aetiological causes of peripheral lymphadenopathy may spare patients from unnecessary evaluation and treatment. In HIV-positive patients, lymph node tuberculosis may be histopathologically unusual and may be suppurative or non-reactive in nearly one-third of patients.

Primary plasmacytoma of testis. Report of a case.

A primary testicular tumour in a 62 year old man was found to be a plasmacytoma on histopathological examination without any extra testicular disease prior to or subsequent to orchiectomy, fulfilling the criteria for the primary extramedullary plasmacytoma. Such cases are extremely rare. Evaluation of such a case was discussed and the relevant literature reviewed.