Human Papillomavirus (HPV): A Criterion for Therapeutic Decision in Squamous Cell Carcinoma of the Head and Neck?

Prognostic Analysis of HPV Status in Sinonasal Squamous Cell Carcinoma

Sinonasal squamous cell carcinoma (SNSCC) is a rare and aggressive malignancy with poor prognosis. Human papilloma virus (HPV) can induce SNSCC although its incidence and impact on patients’ outcomes remains unclear. We performed a retrospective cohort study of patients with SNSCC treated consecutively in a comprehensive cancer center. HPV status was determined with p16 immunohistochemistry followed by RNA in situ hybridization (RNAscope). The incidence, clinical characteristics, and oncologic outcomes of HPV+SNSCC were assessed. P16 prognostic value was evaluated. Fifty-nine patients were included. Eleven (18.6%) SNSCC were p16+ with five (8.4%) doubtful cases. RNAscope was positive in nine cases (15.2%). Patients with HPV+SNSCC were younger (p = 0.0298) with a primary tumor originating mainly in nasal fossa (p < 10−4). Pathologic findings were not different according to HPV status. Among patients who were curatively treated, overall survival was better for HPV+SNSCC (p = 0.022). No prognostic value of p16 expression was reported. Patients with HPV+SNSCC have better oncologic outcomes, probably due to earlier tumor stage with primary location predominantly in the nasal fossa, a more suitable epicenter to perform a surgical resection with clear margins. P16 expression seems not to be a good surrogate of HPV status in SNSCC.

Impact of HPV-associated p16-expression and other clinical factors on therapeutic decision-making in patients with oropharyngeal cancer: A GETTEC multicentric study

OBJECTIVES

To analyze the impact of tumor p16 status and other clinical factors on the therapeutic decision-making process in patients with oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

We conducted a multicenter retrospective study (GETTEC collaborative study group) enrolling all OPSCC patients with a determined p16-status considered eligible for surgery between 2009 and 2014. The impact of p16-status and other clinical factors on the therapeutic decision was evaluated in multivariate analysis.

RESULTS

A total of 476 patients were enrolled in the study, including 244 cases (51%) of p16-positive OPSCC. Overall, 223 (47%) patients underwent primary surgery, and 184 (83%) of them received postoperative radiotherapy ± chemotherapy. More patients with p16-positive OPSCC tended to undergo non-surgical treatment than did patients with p16-negative OPSCC (p = 0.10). Multivariate analysis showed that 5 factors significantly influenced therapeutic management of the patients: T-stage ≥ 3 (towards a non-surgical strategy; p < 0.001), N-stage ≥ 2a (non-surgical strategy; p = 0.02), tumor involvement of the glosso-tonsillar sulcus (surgical strategy; p = 0.002), tumor extension to the oral cavity (surgical strategy; p < 0.009) and the center of care (p < 0.001). The rate of patients directed towards a surgical strategy varied between 9% and 74% depending on the center.

CONCLUSION

There was a non-significant trend to recommend patients with p16-positive OPSCC for non-surgical treatment. Center of care, tumor stage and tumor anatomical subsite and extensions were the main determinants of the treatment choice.

Simultaneous targeting of EGFR, HER2, and HER4 by afatinib overcomes intrinsic and acquired cetuximab resistance in head and neck squamous cell carcinoma cell lines

The epidermal growth factor receptor (EGFR, HER1) is a therapeutic target in head and neck squamous cell carcinoma (HNSCC). After initial promising results with EGFR-targeted therapies such as cetuximab, therapeutic resistance has become a major clinical problem, and new treatment options are therefore necessary. Moreover, the relationship between HER receptors, anti-EGFR therapies, and the human papillomavirus (HPV) status in HNSCC is not fully understood. In contrast to first-generation EGFR inhibitors, afatinib irreversibly inhibits multiple HER receptors simultaneously. Therefore, treatment with afatinib might result in a more pronounced therapeutic benefit, even in patients experiencing cetuximab resistance. In this study, the cytotoxic effect of afatinib as single agent and in combination with cisplatin was investigated in cetuximab-sensitive, intrinsically cetuximab-resistant, and acquired cetuximab-resistant HNSCC cell lines with different HPV status under normoxia and hypoxia. Furthermore, the influence of cetuximab resistance, HPV, and hypoxia on the expression of HER receptors was investigated. Our results demonstrated that afatinib was able to establish cytotoxicity in cetuximab-sensitive, intrinsically cetuximab-resistant, and acquired cetuximab-resistant HNSCC cell lines, independent of the HPV status. However, cross-resistance between cetuximab and afatinib might be possible. Treatment with afatinib caused a G₀ /G₁ cell cycle arrest as well as induction of apoptotic cell death. Additive to antagonistic interactions between afatinib and cisplatin could be observed. Neither cetuximab resistance nor HPV status significantly influenced the expression of HER receptors in HNSCC cell lines. In contrast, the expression of EGFR, HER2, and HER3 was significantly altered under hypoxia. Oxygen deficiency is a common characteristic of HNSCC tumors, and these hypoxic tumor regions often contain cells that are more resistant to treatment. However, we observed that afatinib maintained its cytotoxic effect under hypoxia. In conclusion, our preclinical data support the hypothesis that afatinib might be a promising therapeutic strategy to treat patients with HNSCC experiencing intrinsic or acquired cetuximab resistance.