Human papillomavirus-related small cell carcinoma of the oropharynx: a case report and literature review

Human papillomavirus status and prognosis of oropharyngeal high-grade neuroendocrine carcinoma

BACKGROUND

The prognostic impact of human papillomavirus (HPV) infection or smoking on oropharyngeal high-grade neuroendocrine carcinoma (HG-NEC) is not established.

METHODS

Retrospective study with patients with oropharyngeal HG-NEC seen at MD Anderson Cancer Center from 1997 to 2020, and previously reported patients with oropharyngeal HG-NEC and known p16 and HPV status from the literature review. Survival was estimated with the Kaplan-Meier method, and survival differences assessed with the log-rank test and Cox proportional hazards models.

RESULTS

Thirty patients were included; most had a heavy (≥10 pack-years) smoking history (52%), locoregional disease (stage III-IVB; 77%), and p16-positive tumor (92%). HPV was positive in 65% of tested samples (15/23). Of 24 patients treated with curative intent, the objective response rates was 90% (9/10) and 81% (17/21), respectively, for induction chemotherapy and definitive radiotherapy. During follow-up, 54% (13/24) recurred, mostly (11/13) at distant sites. Median overall survival (OS) was 46 months (95% CI, 14.3 - NA). OS was not associated with HPV status (HR 0.73, P = 0.6) or smoking (HR 1.16, P = 0.8). Among 63 patients with known HPV status after the literature review (19 HPV- and 44 HPV + ), HPV status remained unassociated with OS (P = 0.92).

CONCLUSIONS

This is the largest retrospective cohort of oropharyngeal HG-NEC. Distant recurrence rate after curative treatment was high, suggesting that multimodality treatment including systemic therapy may benefit patients with locally advanced disease. HPV infection did not affect survival outcomes, therefore should not lead to therapy de-intensification for this histology.

High-Grade Neuroendocrine Carcinoma of the Head and Neck: Human Papillomavirus Status and PD-L1 Expression

BACKGROUND

Human papillomavirus (HPV)-related head and neck squamous cell carcinoma represents an important subgroup of head and neck cancer, but HPV occurs also in the less common neuroendocrine carcinomas (NEC). The PD-1/PD-L1 pathway appears to be activated in pulmonary NEC and correlates with a higher mutation burden, but the potential of NEC to respond to checkpoint inhibitors is unknown to a large extent.

OBJECTIVES

To determine the HPV status of NEC of the head and neck region and to investigate the expression of PD-1 and its ligands PD-L1 and PD-L2.

METHODS

Surgical tumor samples from 2006 to 2017 were analyzed. HPV status was determined by p16 immunohistochemistry (IHC) and multiplex PCR. IHC using the Cologne Score was performed for PD-1, PD-L1, and PD-L2.

RESULTS

Seven NEC tumor samples were analyzed, three of them showed HPV type 18. Expression of PD-1 and PD-L1 differed widely and showed no correlation to HPV status. IHC showed an overexpression of PD-L2 in most of the patients.

CONCLUSIONS AND SIGNIFICANCE

A multicentric analysis of NEC is needed to further evaluate the role of HPV as well as immunocheckpoints with regard to inflammatory immune response in genesis and clinical course of this rare tumor entity. Biomarkers for selection of novel treatment regimens, including immunotherapeutic approaches, are warranted.

Human Papillomavirus-Associated Oropharyngeal High-Grade Neuroendocrine Carcinoma in an Adolescent: Case Report and Review of Literature

Oropharyngeal small cell carcinomas (OPSmCC) are rare with only few case reports and case series published in the literature. More recently, an association of these tumors with human papillomavirus (HPV) infection has been detected. However, unlike oropharyngeal squamous cell carcinomas which have a better outcome when associated with HPV, OPSmCC exhibit an aggressive behavior. In this article, we report a case of tonsillar carcinoma arising in a 14-year-old boy that was associated with HPV infection. The tumor exhibited morphologic features of small cell carcinoma with no overt squamous differentiation. Yet, by immunohistochemistry, it showed diffuse and strong co-expression of both squamous and neuroendocrine markers. In addition, we present the clinicopathologic features of all the cases of OPSmCC reported in the literature for which p16 and/or HPV testing have been done.

Cytopathologic characteristics of HPV-related small cell carcinoma of the oropharynx

BACKGROUND

Human papillomavirus (HPV)-related squamous cell carcinoma (SqCC) of the oropharynx is an epidemiologically and clinically distinct form of SqCC that is associated with an improved prognosis. However, HPV-related small cell carcinoma of the oropharynx is a rare and newly described variant that is associated with aggressive clinical behavior and poor outcomes. To date, fewer than 2 dozen reports of this entity exist in the literature, and there is no discussion of cytopathologic features. This article reports 6 cases and discusses the salient cytomorphologic findings, ancillary studies, and challenges when this entity is encountered.

METHODS

Anatomic pathology archives were searched to identify patients with a diagnosis of HPV-related small cell carcinoma of the oropharynx. Medical records were reviewed to document the following: age, sex, smoking status, other relevant clinical history, primary location, treatment, and clinical outcome. Both p16 and high-risk HPV in situ hybridization (ISH) studies were positive in at least 1 specimen from each patient. The pathologic diagnoses, cytomorphologic characteristics, immunocytochemical stains, and HPV ISH studies were reviewed and recorded for all available cases.

RESULTS

Six patients with 11 cytopathology specimens of HPV-related small cell carcinoma of the oropharynx were identified. The mean age was 61.3 years, and all patients died with widely metastatic disease (mean, 23 months; range, 12-48 months). Mixed small cell carcinoma and SqCC components were present in half of the cases.

CONCLUSIONS

The identification of a small cell component can be reliably performed with cytology preparations and is crucial because this (and not the HPV status) determines the prognosis.