Disruptive TP53 mutations in tumor DNA are associated with reduced survival after surgical treatment of squamous-cell carcinoma of the head and neck.

Background Human papillomavirus (HPV) tumor status and surgical salvage are associated with improved prognosis for patients with recurrent oropharyngeal squamous cell carcinoma (OPSCC). Current data regarding types of surgery and the impact of surgery for distant metastatic disease are limited. Methods A retrospective analysis of patients with recurrent OPSCC from two institutions between 2000-2012 was performed. P16 immunohistochemistry and/or in situ hybridization, as clinically available, were used to determine HPV tumor status. Clinical characteristics, distribution of recurrence site and treatment modalities were compared by HPV tumor status. Overall survival was examined by Kaplan-Meier and Cox proportional hazards methods. Results The study included 108 patients with 65 locoregional and 43 distant metastatic first recurrences. The majority were HPV-positive (n=80). HPV-positive tumor status was associated with longer time to recurrence (p<0.01). Anatomic site distribution of recurrences did not differ by HPV tumor status. HPV-positive tumor status (adjusted HR [aHR] 0.23 (95%CI 0.09-0.58), p=0.002), longer time to recurrence (≥1 year; aHR 0.36 (0.18-0.74), p=0.006), and surgical salvage (aHR 0.26 (0.12-0.61), p=0.002) were independently associated with overall survival after recurrence. Surgical salvage was independently associated with improved overall survival compared to non-surgical treatment in both locoregional (aHR 0.15 (0.04-0.56), p=0.005) and distant metastatic recurrence (aHR 0.19 (0.05-0.75), p=0.018). Conclusions Surgical salvage is associated with improved overall survival for recurrent locoregional and distant metastatic OPSCC, independent of HPV tumor status. Further prospective data is needed to confirm the role of surgical salvage for distant metastases.

Purpose To determine if phosphodiesterase 5 (PDE5) inhibitors can augment immune function in head and neck cancer patients through inhibition of myeloid derived suppressor cells (MDSCs). Experimental Design We performed a randomized, prospective, double blinded, placebo controlled, phase II clinical trial to determine the in vivo effects of systemic PDE5 inhibition on immune function in head and neck squamous cell carcinoma (HNSCC) patients. Results Tadalafil augmented immune response, increasing ex vivo T cell expansion to a mean 2.4 fold increase compared to 1.1 fold in control patients (P= 0.01), reducing peripheral MDSC numbers to mean 0.81 fold change compared to a 1.26 fold change in control patients (P=0.001), and increasing general immunity as measured by delayed type hypersensitivity response (P=0.002). Tumor specific immunity in response to HNSCC tumor lysate was augmented in tadalafil treated patients (P=0.04). Conclusions These findings demonstrate that tadalafil augments general and tumor-specific immunity in HNSCC patients and has therapeutic potential in HNSCC. Evasion of immune surveillance and suppression of systemic and tumor specific immunity is a significant feature of head and neck cancer development. This study demonstrates that a PDE5 inhibitor, tadalafil, can reverse tumor specific immune suppression in head and neck cancer patients, with potential for therapeutic application.

In patients with oropharyngeal carcinoma uniformly treated with chemoradiation, the presence of HPV is a favorable prognostic indicator with respect to recurrence and overall survival. However, advanced T stage was an independent risk factor for recurrence and death that can to some degree offset this benefit.