Significance of delayed primary excision in localized nonmetastatic adult head and neck rhabdomyosarcoma

Adult rhabdomyosarcoma ( RMS ) is a highly aggressive tumor. Multidisciplinary treatment is important. However, the role of surgery is controversial. The purpose of this study was to reveal the role of a delayed primary excision ( DPE ) after induction chemotherapy ( IC ) in localized nonmetastatic adult head and neck RMS . We retrospectively reviewed 24 adult head and neck RMS . Treatment was classified into the following two groups: the DPE group, who received IC followed by surgery, postoperative radiotherapy, and adjuvant chemotherapy (17 patients); the chemoradiotherapy ( CRT ) group, who received IC followed by chemoradiotherapy (seven patients). We analyzed the efficacy of IC , local control rate ( LCR ), and overall survival ( OS ). In the DPE group, 10 patients (59%) underwent complete surgical resection. In the evaluation of the surgical specimens, 14 patients (82%) had residual viable tumors after IC . The response to IC was significantly associated with the 3‐year LCR ( CR / PR vs. SD / PD : 100% vs. 33%, P  =   0.0014). In patients with good response to chemotherapy, the DPE group had a significantly better 3‐year LCR compared with that of the CRT group ( DPE group vs. CRT group, 100% vs. 44%, P  =   0.018). However, the treatment modalities were not associated with OS ( DPE group vs. CRT group, 65% vs. 57%: P  =   0.98). The recurrence patterns differed according to treatments, and distant metastases were more frequent in the DPE group. DPE may impact local control of localized nonmetastatic adult head and neck RMS . Poor response to IC is a risk factor for local recurrence.