Conformal radiotherapy in combination with cetuximab for stage Т1–2 tongue cancer with N1–2b regional metastases detected after preventive lymphadenectomy

Abstract
The study objective is to analyze the experience of conformal radiotherapy in combination with cetuximab for cervical lymph node (LN) metastasis in patients with early-stage tongue cancer who had undergone multicomponent surgeries.Materials and methods. This retrospective study included 48 patients with primary squamous cell carcinoma of the tongue (Т1–2) that were treated in Nizhny Novgorod Regional Clinical Oncology Dispensary between 2012 and 2019. The experimental group comprised 25 patients who underwent hemiglossectomy with simultaneous preventive cervical lymph node dissection. The control group was composed of 23 patients who underwent hemiglossectomy alone due to the presence of concomitant somatic pathology. Before surgery, none of the patients had any signs of metastatic lesions in the cervical LNs according to the results of clinical and instrumental examinations. After surgery, 100 % of patients from the experimental group were found to have N1–2b cervical LN metastases at histological examination. Patients from the control group developed clinical signs of cervical LN metastasis within a year after operation. All patients underwent radiotherapy. The experimental group was divided into two subgroups: patients from subgroup 1 (n = 11) received cetuximab due to disease progression, whereas patients from subgroup 2 (n = 14) received cisplatin. Participants from the control group received no chemotherapy due to their concomitant somatic disorders and because regional metastasis was not confirmed.Results. In the control group, the time between surgery and patient’s death varied between 8 and 14 months. Patients from subgroups 1 and 2 survived for 12–60 months and 8–48 months respectively. So far, 9 patients from subgroup 1 and 6 patients from subgroup 2 are alive. Among them, 8 participants from subgroup 1 and 4 participants from subgroup 2 have no signs of disease progression. Three patients from subgroup 2 died of cardiovascular diseases (they had no cancer progression within 3 months after the completion of chemotherapy).Conclusion. Preventive lymph node dissection in patients with stage Т1–2 tongue cancer enables early detection of subclinical N1–2b metastases and ensures timely initiation of therapy. Our experience confirmed safety of cetuximab plus radiotherapy used to improve disease control and increase patient’s survival.