Oral carcinoma cuniculatum: an unacquainted entity with diagnostic challenges—a case report

Background Oral carcinoma cuniculatum (OCC) is an unacquainted well-differentiated subtype of oral squamous cell carcinoma, which displays unique clinic-pathological features. Up to date, OCC remains rare with about 75 reported cases, and is frequently missed or even misdiagnosed. Case presentation The aim of the present work was: to report a case of OCC in mandibular gingiva and to highlight its main clinic-pathological diagnostic features: with an exophytic cobble-stone surface and a characteristic endophytic burrowing architecture, as well as to differentiate between it and other closely similar lesions including verrucous carcinoma, papillary squamous cell carcinoma, and well-differentiated conventional oral squamous cell carcinoma. Conclusions An accurate diagnosis of OCC entails awareness of the clinicians and pathologists about its entity, proper knowledge of the diagnostic clinical and histopathological evidence, and the ability to differentiate it from closely similar lesions.

Carcinoma Cuniculatum with Bone Invasion Mimicking a Viral Wart

Carcinoma cuniculatum is a rare variant of low-grade and well-differentiated squamous cell carcinoma. It is a locally invasive tumor, although it has low metastatic potential. It was originally described in the plantar region but may exceptionally appear in other locations. It predominates in middle-aged men and presents clinically as an exophytic, solitary, painful tumor, with insidious growth. Histologically, this tumor simulates a variety of benign dermatoses and may require several biopsies for the correct diagnosis. It is often misdiagnosed as a viral wart, due to the clinical similarity and the indolent course. The treatment of choice is surgical excision due to the high risk of recurrence and locally aggressive behavior. Amputation can be performed in cases of deep tissue invasion. We present a case of carcinoma cuniculatum in which the late diagnosis favored the invasion of the underlying bone, resulting in amputation of the affected finger.