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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Progressive transformation of germinal centers (PTGC) is a precursor lesion of -
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The correct answer is  Lymphocytic predominance contains lymphocytic and histiocytic (L and H) variant. Thesse variants express B cell markers typical of germinal centre B cells. The IgH genes of L and H variant show evidence of ongoing somatic hypermutation,a modification that occurs only in germinal centre B cells. In 3%to5% of cases this type transforms in to a tumour resembling diffuse large B cell lymphoma. Reference; Robbins and Cotran Pathologic basis of disease.South Asia Edition volume 1.page no. 609,610