Osseous metaplasia in neoplastic and non-neoplastic lesions: A comprehensive case series of 30 patients from a tertiary care center

Background: Osseous metaplasia (OM), distinct from calcification, is a rare histological event reported across various organs in both neoplastic and non-neoplastic contexts, typically as isolated case reports. Objective: This study presents a series of 30 cases of OM from diverse anatomical sites, aiming to broaden the understanding of its pathogenesis and clinical significance. Material and Methods: A retrospective and prospective histopathological study was conducted over 12 months (August 24 to August 25) in a tertiary care center. Inclusion criteria encompassed all cases of OM confirmed on histology; cases lacking sufficient clinical or tissue data were excluded. Results: Eighteen cases (19 males, 11 females; age range: 31–74 years) were included. The most frequent sites were the thyroid, kidney, followed by lung, bladder, endometrium, and breast. Conclusion: This is one of the largest single-center series documenting OM across a spectrum of lesions. Recognizing OM can aid in accurate histological interpretation and may have prognostic value in certain tumors.