A Solitary Phlebolith in the Buccal Mucosa: Report of a Rare Entity and Clinicopathologic Correlation.

Pathological conditions can give rise to calcifications within oral mucosa representing either a local or systemic disturbance. Inflammation, trauma, debris acting as nidus and vascular lesions have been attributed as principal causes for occurrence of calcifications within the oral mucosa. Occurrence of multiple calcified thrombi (phleboliths) is considered pathognomonic for hemangiomas and vascular malformations in the oral and maxillofacial region. Isolated occurrence of phlebolith in oral mucosa though very rare, especially without any underlying vascular lesions, can be diagnostically challenging. Either a traumatic association at that site or a hemangioma of childhood that has regressed once the individual became an adult are the possible explanations suggested for the occurrence of these unique solitary phleboliths. Histologically, an "onion-ring"-like concentric lamellar fibrosis around a central core with varying amounts of calcifications and presence of minute vascular channels within or around calcified lamellae is characteristic for phlebolith. There is a high propensity for misdiagnosing solitary phlebolith located in sites like the buccal mucosa where various other pathologic soft-tissue calcifications, such as sialoliths, calcified lymph nodes, traumatic myositis ossificans, etc. can occur and they too appear radiopaque in radiographs. Besides, the absence of any associated underlying vascular lesion adds to the mispercep-tion. In such cases, histopathological examination with routine hematoxylin and eosin staining alone may not be sufficient to determine the accurate diagnosis. Allied clinical history and immunohistochemistry can aid to arrive at the final diagnosis. We report such a case of nonvascular lesion-associated solitary phlebolith in the right buccal mucosa of a healthy 49-year-old male patient and discuss its differential diagnosis with emphasis on histological presentation.