A clinicopathologic study of mediastinal lesions with special emphasis on thymomas.

Background: Mediastinal masses are relatively uncommon lesions that sometimes pose an interesting diagnostic and therapeutic problem for the clinician. Thymomas are one of the common mediastinal neoplasms and exhibit a wide spectrum of morphologic features and an unrivalled frequency of other autoimmune diseases. The great morphologic variability and heterogeneity in thymomas has rendered their histological classification difficult and highly controversial. Methods: This retrospective and descriptive study on thymoma was done in the department of pathology, Kasturba Medical College Mangalore (Manipal University), India over a period of five years from January 2006 to June 2011. Histopathology sections taken were stained with routine Hematoxylin and Eosin stains in every case. Additional stains and immunohistochemistry were done as required. Results: Total number of mediastinal lesions studied was 66, with thymomas making up 15 cases. The age range of patients with thymomas was 22 to 65 years with a mean of 48 years. The most common histologic sub-type of thymoma was B2. Type AB thymoma was associated with bad prognosis. Five cases of thymomas were associated with Myasthenia Gravis. All thymomas showed cytokeratin positivity. Reticulin fibers were seen around individual tumor cells in Type A thymoma while Type B2 showed around tumor nests. Conclusion: Thymomas are rare & interesting neoplasm located in the mediastinum. A histomorphological analysis aided by immunohistochemistry and radiology permits an exact diagnosis and also allows for differentiation between benign and malignant neoplasms.

Clinical, biochemical & cytomorphologic study on Hashimoto’s thyroiditis.

Background & objectives: Despite, the extensive salt iodization programmes implemented in India, the prevalence of goiter has not reduced much in our country. The most frequent cause of hypothyroidism and goiter in iodine sufficient areas is Hashimoto’s thyroiditis (HT). This study records the clinical presentation, biochemical status, ultrasonographic picture and cytological appearance of this disease in a coastal endemic zone for goiter. Methods: Case records of patients with cytological diagnosis of HT were studied in detail, with reference to their symptoms, presence of goiter, thyroid function status, antibody levels and ultrasound picture. Detailed cytological study was conducted in selected patients. Results: A total of 144 patients with cytological proven HT/lymphocytic thyroiditis were studied. Ninety per cent of the patients were females and most of them presented within five years of onset of symptoms. Sixty eight per cent patients had diffuse goiter, 69 per cent were clinically euthyroid and 46 per cent were biochemically mildly hypothyroid. Antibody levels were elevated in 92.3 per cent cases. In majority of patients the sonographic picture showed heterogeneous echotexture with increased vascularity. Cytological changes were characteristic. Interpretation & conclusions: our study showed predominance of females in the study population in 21-40 yr age group with diffuse goiter. We suggest that in an endemic zone for goiter, all women of the child bearing age should be screened for HT.

A clinicopathological study of interface dermatitis.

Background: Interface dermatitis (ID) refers to a pattern of skin reaction characterized by an inflammatory infiltrate that appears to obscure the dermoepidermal junction when observed at low power examination and referred to as lichenoid tissue reaction. A wide range of inflammatory skin diseases exhibits interface change with considerable overlap of histological features. The aim of the present study was to study the clinical features and microscopic features of ID. Materials and Methods: The material for the present study consisted of skin biopsy samples collected from patients attending the outpatient Department of Dermatology. The study was conducted for a period of 3 years from 2007 to 2010. During this period, a total of 125 cases was studied. Results: In the present study, a total of 125 cases of ID was studied which presented clinically as papulosquamous disorders. Majority of the cases of ID were seen in women (57.6%). Majority of ID were lichen planus (LP) and its variants (63.2%). Clinicopathological concordance was seen in 109 cases (87.2%) and discordance in 16 cases (12.8%). Conclusion: The mere presence of an interface lichenoid inflammatory reaction should not be the sole criterion for the diagnosis of LP or one of its many variants, as now seems to be the case. A clinicopathologic correlation is absolutely essential for a conclusive diagnosis of ID.

Rare association of papillary carcinoma of thyroid with adult T-cell lymphoma/leukemia.

Papillary carcinoma is the most common malignant tumor of the thyroid, especially in countries with adequate or excess iodine in diet. Many studies indicate that a sizable number of papillary cancer cases occur in a setting of chronic thyroiditis. But the tumor that arises more frequently in thyroiditis is malignant lymphoma. We report a rare association of papillary carcinoma of thyroid in an elderly lady with adult T-cell lymphoma/leukemia. Fine needle aspiration of the thyroid, neck nodes and evaluation of the bone marrow and peripheral blood helped in the diagnosis of papillary cancer coexisting with adult T-cell lymphoma/leukemia.

Bone marrow biopsy in non-Hodgkin lymphoma: A morphological study.

Context: Bone marrow (BM) biopsy is an integral part of staging work-up for non-Hodgkin lymphoma (NHL). Aims: To study the characteristics of BM involvement in NHL with respect to incidence, histologic pattern and morphology of infiltration and its discordance with the histology of primary anatomic site. Settings and Design: Forty-nine cases of NHL in which BM biopsy was performed for staging were included in this study, the primary site being classified according to the WHO classification for NHL. Materials and Methods: A prospective study of 49 cases was conducted. Bilateral BM biopsy was obtained from the posterior superior iliac spine. The biopsies were fixed in 10% buffered formalin solution and decalcified using 10% formal - formic acid for 4 - 6 h followed by routine processing. The serial sections were stained by hematoxylin and eosin and reticulin stains. Results: BM biopsy showed involvement by lymphoma in 27 cases (55.10%). Unilateral positivity was found in four cases (14.81% cases). The overall incidence of marrow involvement by NHL was 55.1%. The incidence of involvement was higher in T-cell lymphomas when compared with B-cell lymphomas and predominant pattern of involvement was mixed. Diffuse large B-cell lymphomas had the lowest incidence in all the B-cell lymphomas. A discordant histology between BM and primary anatomic site was found in 29.63% (8/27) of the cases, where it was seen more in follicular lymphomas and diffuse large B-cell lymphomas. Conclusions: Critical examination of BM biopsies can increase the diagnostic accuracy, thereby contributing to the prognosis and appropriate treatment modalities.

Langerhans cell histiocytosis of mediastinal node.

The predominant clinical and radiological features of Langerhans Cell Histiocytosis (LCH) in children are due to osseous involvement. Extra-osseous disease is far less common, occurring in association with bone disease or in isolation. In the present study, LCH was presumptively diagnosed on Ultrasound guided Fine needle aspiration cytology (FNAC) of the mediastinal lymph node in a 18 month-old child. The diagnosis was confirmed by histological examination of the biopsy material.S-100 protein localization in the LCH cells is often positive on immunohistochemistry.

Mucoepidermoid carcinoma of lung: a case report.

Mucoepidermoid lung tumours are uncommon neoplasms comprising of 0.2% of all the lung tumours and historically included under the term bronchial adenomas. This is a case report of a bronchial tumour in the hilar region present since 3 years. The neoplasm could be easily classified as a mucoepidermoid tumour of low malignant potential, as it resembled the histologically identical lesion in the main salivary glands. The case is reported for its rarity and for the histological evaluation of the malignant potential in an apparently clinically benign neoplasm.