Sasima Eimpunth1, Alina Goldenberg, Michael Shane Hamman, Gagik Oganesyan, Robert A Lee, Saowalak Hunnangkul, Silvia Soohyun Song, Tanya Greywal, Shang I Brian Jiang. 1. *Department of Dermatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; †Department of Dermatology, University of California, San Diego, Medical Center, La Jolla, California; ‡Compass Dermatopathology, La Jolla, California; §Department of Dermatology and Mohs Surgery, Southern California Permanente Medical Group, Fontana, California; ‖Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; ¶Department of Dermatology, University of Pittsburgh Medical Center Health System, Pittsburg, Pennsylvania.
Abstract
BACKGROUND: Shave biopsy may not be able to accurately distinguish squamous cell carcinoma in situ (SCCIS) from invasive squamous cell carcinoma (SCC). Information on the incidence of biopsy-proven SCCIS upstaged to SCC after a more complete histologic examination is limited. OBJECTIVE: To determine the incidence and clinical risk factors associated with upstaging the biopsy diagnosis of SCCIS into invasive SCC based on findings during Mohs micrographic surgery (MMS). METHODS: All MMS cases of SCCIS performed between March 2007 and February 2012 were identified, MMS operative notes were examined, and invasive dermal components were confirmed by the MMS slide review. Upstaged SCCIS was defined as biopsy-diagnosed SCCIS subsequently found to be an invasive SCC during MMS. RESULTS: From 566 cases with the preoperative diagnosis of SCCIS, 92 (16.3%) cases were SCCIS upstaged to SCC. Location of ears, nose, lips, and eyelids, preoperative diameter >10 mm, and biopsy report mentioning a transected base were significant predictors of upstaged SCCIS. CONCLUSION: Considering the possibility that over 16% of SCCIS may be truly invasive SCC, biopsy-proven SCCIS should be treated adequately with margin-assessed treatment modalities such as surgical excision or Mohs surgery when indicated.
BACKGROUND: Shave biopsy may not be able to accurately distinguish squamous cell carcinoma in situ (SCCIS) from invasive squamous cell carcinoma (SCC). Information on the incidence of biopsy-proven SCCIS upstaged to SCC after a more complete histologic examination is limited. OBJECTIVE: To determine the incidence and clinical risk factors associated with upstaging the biopsy diagnosis of SCCIS into invasive SCC based on findings during Mohs micrographic surgery (MMS). METHODS: All MMS cases of SCCIS performed between March 2007 and February 2012 were identified, MMS operative notes were examined, and invasive dermal components were confirmed by the MMS slide review. Upstaged SCCIS was defined as biopsy-diagnosed SCCIS subsequently found to be an invasive SCC during MMS. RESULTS: From 566 cases with the preoperative diagnosis of SCCIS, 92 (16.3%) cases were SCCIS upstaged to SCC. Location of ears, nose, lips, and eyelids, preoperative diameter >10 mm, and biopsy report mentioning a transected base were significant predictors of upstaged SCCIS. CONCLUSION: Considering the possibility that over 16% of SCCIS may be truly invasive SCC, biopsy-proven SCCIS should be treated adequately with margin-assessed treatment modalities such as surgical excision or Mohs surgery when indicated.