Oncologic Outcomes for Squamous Cell Carcinoma In Situ With a Clinically Resolved Biopsy Site Managed by Watchful Waiting.

BACKGROUND

Treatment option decisions for low-risk squamous cell carcinoma in situ (SCCIS) are hampered by a paucity of management-type-specific outcomes data.

OBJECTIVE

Describe SCCIS tumor outcomes managed by watchful waiting and risk factors associated with poor cancer outcomes.

MATERIALS AND

METHODS

Retrospective cohort study.

Setting

Single academic hospital in a rural setting. Patients: Adults with SCCIS diagnosed between January 01, 2014, and December 31, 2016. Main Outcomes and Measures: Hazard ratios (HRs) for local recurrence (LR), nodal metastases (NM), distant metastases (DM), and disease-specific death (DSD).

RESULTS

A total of 411 consecutive SCCIS tumors that were considered clinically resolved at follow-up and managed with watchful waiting were included. Seventeen tumors recurred locally. No instances of NM, DM, or DSD were identified. Multivariate analysis found that solid-organ transplant recipient status conferred the highest risk of local recurrence [HR, 9.979 (95% CI, 2.249-39.69)]. Additional risk factors predicting LR include anatomic location on the vermilion lip or ear [HR, 9.744 (95% CI, 1.420-69.28)], anatomic location on the head and neck [HR, 6.687 (95% CI, 1.583-36.15)], and a biopsy with tumor extending to the deep edge [HR, 6.562 (95% CI, 1.367-39.04)].

CONCLUSION

Watchful waiting for SCCIS with a clinically resolved biopsy site has a local recurrence rate of 4%.