RESUMEN
Spontaneous regression of a neoplasm is a rare oncologic phenomenon. Certain neoplasms, such as melanomas and neuroblastomas, display this phenomenon. To date, spontaneous regression of oral cavity squamous cell carcinomas has been documented in only a handful of case reports. We present a novel case of spontaneous regression of an oral tongue squamous cell carcinoma following biopsy. We discuss the tumor's unique genetic profile, immune response to cancer, and review the literature on possible mechanisms of spontaneous regression. Small-volume persistent cancer in our patient reinforces that tissue confirmation remains crucial to avoid missing remaining tumor. Further investigation is required to understand mechanisms of spontaneous regression and how these may be exploited to improve head and neck squamous cell carcinoma treatment.