C-cell hyperplasia in sporadic and familial medullary thyroid carcinoma

Context: C-cell hyperplasia (CCH) is characterized by increased mass of C-cells and has been identified as a precursor condition for medullary thyroid carcinoma (MTC). Varying proportion of MTCs is associated with CCH in different studies. This could be due to the lack of uniformity of the definitions and techniques used to identify CCH in these studies. Aims: This study aims to study the occurrence, clinicopathological, and immunohistochemical features of CCH in MTC diagnosed during a 22-year period at a tertiary care center in North India and to review the available literature on CCH. Materials and Methods: Eighty-seven consecutive cases of MTC were included in the study. Histological evaluation for the presence of CCH and neoplastic CCH was performed. Confirmation of CCH was done by immunohistochemistry for calcitonin and chromogranin. The presence of neoplastic CCH was correlated with clinical factors and prognostic factors. Results: Of 87 cases of MTC included in the study, 71 (82%) patients were sporadic and 16 (18%) had familial MTC. Neoplastic CCH was seen in 12 (75%) familial and in 9 (13%) sporadic MTC. Patients with familial MTC were more frequently associated with neoplastic CCH than sporadic MTC (P < 0.001), were younger (P < 0.001), and had more often bilateral and multifocal tumors (P < 0.001). However, there was no significant difference in mean survival time and progression-free survival in patients with and without CCH. Conclusion: CCH, though more common in familial MTC, can also be seen in sporadic tumors. CCH is not associated with patient survival and disease progression.

Extranodal histiocytic sarcoma in a child with acute lymphoblastic leukemia: Cytomorphological features of a rare entity with brief review of literature

Histiocytic sarcoma (HS) is a rare malignant neoplasm showing morphologic and immunophenotypic evidence of histiocytic differentiation. We describe a rare case of synchronous HS in a patient of B-cell acute lymphoblastic leukemia (ALL). A 16-year-old boy diagnosed as ALL also presented with a swelling over the right Achilles tendon. The cytological features of the swelling suggested a histiocytic lesion. Histological and immunohistochemical examination clinched the diagnosis of HS. The available 5-year follow-up showed no recurrence. It was a diagnostic dilemma on fine-needle aspiration. We discuss the cytological features of HS which can help in reaching a diagnosis and emphasize that it should be considered in the differential diagnosis for unexplained swellings in patients of hematological malignancies. Wide local excision of localized HS is associated with a long-term favorable outcome.

Bone marrow oxalosis: An unusual cause of cytopenia in end-stage renal disease; report of two cases

Systemic oxalosis can be either primary or secondary hyperoxaluria. Oxalosis is a phenomenon in which calcium oxalate crystals deposit in various visceral organs leading to bone marrow (BM) failure and recurrent renal stones. We describe two rare cases of BM oxalosis. Hyperoxaluria is strongly associated with nephrolithiasis and nephrocalcinosis. Both the patients presented with recurrent renal stones and a variable degree of BM failure. BM oxalosis should be considered as a possible diagnosis in patients in recurrent nephrolithiasis and cytopenia.