Austen Callister
Patterns and Risk Factors of Recurrent SCCis with Follicular Involvement
Mentor: Doug Grossman, MD, PHD
Department: Dermatology
Background: Occasionally, squamous cell carcinoma in situ (SCCis) displays follicular involvement (SCCis-foll) histologically. Recurrence patterns and risk factors for recurrence of this particular tumor subtype have not been well studied.
Objective: To determine the rate of recurrence of SCCis-foll and factors that may be associated with recurrence.
Methods: Medical records of consecutive patients diagnosed with SCCis-foll from 2015-2019 were reviewed. Initial and follow-up biopsy specimens of those with tumor recurrence following treatment were histologically reviewed, along with initial biopsy specimens of an internal control group without recurrence.
Results: Of approximately 9355 SCCis patients, a total of 962 (10.3%) had SCCis-foll and of these 63 (6.5%) had confirmed tumor recurrence. Tumors that recurred appeared to be associated with scalp location and immunosuppression, but not with depth of follicular involvement, treatment modality, or patient demographic factors. Statistical analysis is in progress.
Limitations: The incidence and recurrence rate of SCCis-foll may have been underestimated if some cases were not initially diagnosed as such or followed for sufficient time to observe recurrence, respectively.
Conclusions: Risk of recurrence of SCCis-foll is low, and does not appear to be associated with depth of follicular involvement, treatment modality, or other patient demographic factors.