Impact of routine surveillance imaging on detecting recurrence in human papillomavirus associated oropharyngeal cancer.

OBJECTIVES: This study examines the utility of surveillance imaging in detecting locoregional failures (LRF), distant failures (DF) and second primary tumors (SPT) in patients with human papillomavirus (HPV) associated oropharyngeal cancer (OPC) after definitive chemoradiotherapy (CRT). METHODS AND MATERIALS: An institutional database identified 225 patients with biopsy proven, non- metastatic HPV+ OPC treated with definitive CRT between 2004 and 2015, whose initial post-treatment imaging was negative for disease recurrence (DR). Two groups were defined: patients with <2 scans/year Group 1 and patients with ≥2 scans/year Group 2. The Mann-Whitney test or Chi-square was used to determine differences in baseline characteristics between groups. Fine & Gray regression was used to detect an association between imaging frequency, DR and diagnosis of SPT. RESULTS: Median follow up was 40.8 months. 30% of patients had ≥T3 disease and 90% had ≥ N2 disease (AJCC 7th edition). Twenty one failures (9.3%) were observed, 7 LRF and 15 DF. Six LRF occurred within 24 months and 14 DF occurred within 36 months of treatment completion. Regression analysis showed Group 2 had increased risk of DR compared to Group1 (HR 10.3; p = 0.002) albeit with more advanced disease at baseline. Five SPT were found (2 lung, 2 esophagus, and 1 oropharynx) between 4.5 and 159 months post-CRT. CONCLUSION: Surveillance imaging seems most useful in the first 2-3 years post treatment, and is particularly important in detecting DF. Surveillance scans for SPT has a low yield, but should be considered for those meeting lung cancer screening guidelines.

Early and Severe Radiation Toxicity Associated with Concurrent Sirolimus in an Organ Transplant Recipient with Head and Neck Cutaneous Squamous Cell Carcinoma: A Case Report.

We present a case of a 71-year-old man with a history of liver transplantation who was treated with adjuvant radiotherapy with concurrent cisplatin for recurrent cutaneous squamous cell carcinoma of the head and neck. The patient was transitioned from tacrolimus to sirolimus for immunosuppression immediately prior to the start of radiation therapy, with the goal of reducing the risk for further skin cancer recurrence. The patient developed severe normal tissue toxicity, disproportionate to the dose delivered. He was diagnosed with Grade 4 esophagitis and mucositis after just 2,400 cGy in 12 fractions (planned 6,400 cGy in 32 fractions), requiring cessation of therapy. Six months later, the patient was diagnosed with local recurrence and distant metastases in the lung, and unfortunately passed away one month later. Randomized data have demonstrated the anti-neoplastic benefit of sirolimus. Pre-clinical studies and animal models have suggested that sirolimus may be a radiation sensitizer; however, the literature is limited regarding the clinical translation of these biologic findings. The case we presented reflects that concurrent radiation therapy with sirolimus may enhance the cytotoxic effects of radiation therapy and contribute to dose-limiting toxicity. Certainly, further study is necessary to explore this observation.