Intensity‐modulated radiotherapy combined with intensity‐modulated radiotherapy CT–guided iodine 125 seed brachytherapy for non‐small cell lung cancer: A case report

Intensity‐modulated radiotherapy (IMRT) has been used to treat locally advanced non‐small cell lung cancer (LA‐NSCLC) disseminated to primary gross tumor volume (pGTV) and mediastinal lymph nodes (LNs). However, it is challenging to deliver definitive doses to the pGTV and regional LNs without exceeding the tolerance of the organs at risk (OAR). Iodine‐125 (I‐125) brachytherapy has recently been applied in clinical practice for the treatment of malignant tumors. Its merits include a higher dose to the primary tumor lesion and lower dose surrounding the tumor mass. Using brachytherapy in these settings may maximize the dose delivered to the pGTV while minimizing the dose delivered to the OAR. I‐125 brachytherapy combined with IMRT for the treatment of LA‐NSCLC has rarely been reported. Here we report a patient with peripheral squamous cell carcinoma of the lung who received I‐125 brachytherapy for pulmonary lung lesions and IMRT for metastatic mediastinal LNs. The patient received 16 months of follow‐up care with no evidence of complications or disease recurrence. Moreover, we compared brachytherapy plus IMRT to theoretically planned IMRT dosimetry to evaluate the merits of each approach. This treatment modality resulted in a higher target dose escalation and lower doses delivered to the OAR.