A clinicopathological and immunohistochemical study of non-urothelial bladder tumours

BACKGROUND: Non-urothelial bladder tumors (NUBTs) are uncommon accounting for approximately 10% of the total urinary bladder tumors while 90% are urothelial in origin. There are very limited comprehensive studies on NUBTs. AIMS AND OBJECTIVES: The objectives of the study were to analyze the clinicopathological and immunohistochemical features of NUBTs. MATERIALS AND METHODS: This is a retrospective study of NUBTs diagnosed over a period of 9 years. Patients' files were retrieved from the archives. Gross and microscopic features were recorded. Simple percentage and frequencies were used to interpret the data. RESULTS: A total 16 cases (10.8% of all bladder tumors) of NUBT were found. Patients' ages ranged from 19 to 87 years with a male: female ratio of 4.3:1. The most common presenting symptom was gross hematuria (81.2%), and the most common location was posterolateral bladder wall. Muscle invasion was seen in 81.2% of cases, and large areas of necrosis were observed in 62.5%. There were two cases of squamous cell carcinoma, five cases each of adenocarcinoma (four secondary and one urachal) and mesenchymal tumors (four malignant and one benign), two cases of amyloid, and one case each of plasmacytomas and paraganglioma. Large areas of necrosis and muscle invasion were noted in high-grade and advanced staged tumors. In all, 43.7% had poor survival. CONCLUSION: NUBTs present with similar clinicoradiological findings; however, their histological features along with immunohistochemistry help in the definite diagnosis. One should be aware of these tumors as they frequently present diagnostic and therapeutic challenge. Most of these neoplasms present at an advanced stage. Large or multicentric randomized controlled studies are needed to know the exact behavior and prognosis of these tumors.

Reappraisal of morphological and immunohistochemical spectrum of intracranial and spinal solitary fibrous tumors/hemangiopericytomas with impact on long-term follow-up

BACKGROUND: Hemangiopericytomas (HPCs) and solitary fibrous tumors (SFTs) are unique entities in the central nervous system (CNS) and even rarer in the spine with propensity to recurrence and metastasis. Both these tumors were detected to share the NAB2–STAT6 fusion gene with frequent morphologic overlap that necessitated the need for the combined term SFT/HPC in the CNS by the World Health Organization (WHO) in 2016. AIMS: This study aims to describe the clinical outcome of intracranial and spinal SFT/HPCs based on detailed histomorphologic and immunohistochemical features. MATERIALS AND METHODS: A retrospective analysis of these tumors was conducted over a period of 10 years from January 2006 to January 2017 at our institute. Based on the elaborative assessment of morphology and immunohistochemistry, these tumors were categorized into three grades as per WHO criteria. RESULTS: A total of 13 cases were encountered involving mainly extra-axial and supratentorial regions. Among intracranial HPCs, anaplastic subtypes constituted significantly higher proportion (39%) when compared with peripheral HPCs. Peculiar morphological patterns like micropapillae and pseudoangiomatous arrangement of tumor cells were observed in high-grade tumors. A panel of immunomarkers were used to confirm the diagnosis and rule out other mimickers. Gross total resection was achieved in 54% (7/13) of the cases with local recurrence observed in 31% (4/13). Grade II tumors showed recurrence in 28% cases. No case showed distant metastasis. CONCLUSION: To conclude, not just clinical parameters but morphologic features such as unusual patterns, mitosis, and proliferative index also play a pivotal role in predicting the clinical behaviour of SFT/HPC.

Extensive intestinal metaplasia of renal pelvis: Report of a case and literature review.

Transformation of the urothelium to the intestinal type of epithelium is rare in the pelvis with very few cases reported in the literature. The present study reports extensive intestinal metaplasia of the pelvi-calyceal system without residual urothelium in a 35-years-old woman with a 2 years history of renal calculi. Right - sided Nephrectomy was undertaken. Immunohistochemistry of the metaplastic epithelium revealed positive expression of CK20, low Ki-67 index and negative expression of p53. In this patient long standing metaplastic changes did not progress to adenocarcinoma which indicates that extensive intestinal metaplasia is not always associated with malignancy.

Isolated lacrimal gland involvement in Rosai-Dorfman-Destombes disease.

Rosai-Dorfman-Destombes (sinus histiocytosis with massive lymphadenopathy) disease is an uncommon disease characterized by benign proliferation of histiocytes, with painless lymph node enlargement and frequent extranodal disease. Orbital involvement occurs in 9-11% of cases. However, isolated Rosai-Dorfman-Destombes disease of the lacrimal gland without any systemic involvement is very rare with only three case reports. We describe here one such young male patient with unilateral lacrimal gland swelling. Excision biopsy revealed almost complete replacement of the lacrimal gland by lymphocytes, plasma cells and large pale histiocytes. The latter exhibited emperipolesis and stained positive for S-100 and CD68 on immunohistochemistry. Patient is well and has no other manifestation or recurrence of the disease during a follow-up of 24 months.

Mucin-producing signet ring cell adenoma of the thyroid.

Signet ring cell adenoma of the thyroid, though rare, is well documented. This change is chiefly due to intracellular accumulation of thyroglobulin that appears mucinous. Awareness of this entity is important as it may closely simulate a metastatic mucin-secreting signet ring cell carcinoma. Although the mucinous material in signet ring cells has been reported to stain positive with thyroglobulin, in some cases it may not be so. We herein describe a rare case of a 46-year-old man who was hypothyroid and the mass removed from the thyroid showed a mucin-producing signet ring cell adenoma of the thyroid.

Pathology and pathogenesis of rheumatic heart disease.

Cardiovascular disease is on the rise. In India and other developing countries, rheumatic heart disease (RHD) continues to be a major public health problem and contributes to significant cardiac morbidity and mortality. RHD in the juvenile age group namely juvenile mitral stenosis is a variant which is unique to the Indian subcontinent. Severe valve deformities lead to high morbidity and mortality. Despite various measures no appreciable decline in prevalence of RHD has been documented. At autopsy, mitral valve was most commonly affected either alone or in combination with aortic and tricuspid valves. Both functional and organic involvement of tricuspid valve was documented. It has been convincingly demonstrated that molecular mimicry between Streptococcus pyogenes antigen and human proteins lead to autoimmune reactions both humoral and cell mediated causing RF/RHD. Heart tissues namely the valves, left atrial appendage (LAA) and myocardium reveal variable amounts of infiltration by lymphocytes. Significant endocarditis and valvulitis is observed in these cases. CD4+ T cells are most likely the ultimate effectors of chronic valve lesions in RHD. They can recognize Streptococcal M5 protein peptides and produce various inflammatory cytokines such as TNF-alpha, IFN-gamma, IL-10, IL-4 which could be responsible for progressive fibrotic valvular lesions. Cardiac myosin has been defined as a putative autoantigen recognized by autoantibodies of RF patients. Cross reactivity between cardiac myosin and group A beta hemolytic Streptococcal M protein has been adequately demonstrated. Cardiac myosin has been shown to produce myocarditis in rats and mice. Valvulitis/ endocarditis has been observed in excised LAA, cardiac valves and in hearts at autopsy from cases of RHD. The disease predominantly affects the valvular endocardium culminating in crippling valve deformities. Endocardial infiltrate and their migration into the valve substance has been elegantly demonstrated in rats and mice. Immune responses against cardiac myosin lead to valvular heart disease and infiltration of the heart by Streptococcal M protein reactive T lymphocytes. Mitral valves showed various degrees of calcification. An interesting observation is the nature of calcification in diseased/distorted valves in RHD. Recent studies indicate that calcification is not merely an inactive, "dystrophic" process but involves a regulated inflammatory process associated with expression of osteoblast markers and neoangiogenesis. Increased plasma osteopontin levels correlated with severity of mitral valve calcification. Further evidence of inflammation is supported by high levels of advanced oxidation protein products and high sensitive C-reactive protein in plasma detected in patients with RHD. Presence of inflammatory cells and increased expression of several cytokines in cases of "end stage" RHD reflects a possible subclinical, ongoing insult/injury to some unrecognized antigenic stimulus by beta hemolytic Streptococcal antigens that have sensitized/primed the various target tissues and which further culminate in permanent valve deformities.