Adapting Surgery to Radiotherapy Response in T4b Sinonasal Squamous Cell Carcinoma: Insights from a Multicenter Retrospective Study

Summary: The prognosis of T4b Sinonasal squamous cell carcinoma (SNSCC) remains poor, necessitating multidisciplinary approaches to improve patient outcomes. This study evaluated the efficacy of the response-adapted strategy in patients with T4b SNSCC. This retrospective study analyzed consecutive patients with T4b SNSCC treated between January 1999 and January 2019 at three tertiary academic centers. Patients received radiotherapy and were then divided into response and non-response groups according to whether achieving objective response after radiotherapy. Subsequently, patients received either surgery or best supportive care (BSC). Endpoints included overall survival (OS), locoregional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS). One hundred thirty-four patients were enrolled, with 98 (73%) achieving objective responses and 36 (27%) not. The median follow-up time was 74.74 months. In the response group, surgery significantly improved 5-year OS (56.6% vs. 28.8%, p < 0.001), LRFS (51.7% vs. 20.8%, p = 0.002), and DMFS (54.9% vs. 26.9%, p < 0.001) compared to BSC. However, in the non-response group, no significant difference was observed in OS, LRFS, or DMFS between the surgery and BSC groups. Surgical complications were infrequent, even in the context of radiotherapy. Furthermore, patients who underwent surgery encountered fewer acute side effects related to radiation, mainly due to the lower radiation dose than those receiving the best supportive care (BSC). For T4b SNSCC patients who responded to radiotherapy, surgery demonstrated a survival advantage over BSC; non-responders may not benefit from surgery. The strategy of radiotherapy response-adapted addition of surgery proved survival advantage and warranted prospective validation. Qian Liu, MD (Presenting Author) - Cancer Hospital, Chinese Academy of Medical Science; Zeliang Ma (he/him/his), MD (Co-Author) - Cancer Hospital, Chinese Academy of Medical Science; Jingwei Luo, MD (Co-Author) - Cancer Hospital, Chinese Academy of Medical Science