Second primary malignant peripheral nerve sheath tumor of the paranasal sinuses after nasopharynx carcinoma

Demographic, Clinical and Histopathological Features of Oral Neural Neoplasms: A Retrospective Study

Intraoral neural neoplasms though unusual may be clinically significant. The aim of this study was to categorize and evaluate oral neural tumors in a large oral pathology biopsy service. With IRB approval, a retrospective search of all neural neoplasms of the oral cavity in the archives of the University of Florida Oral Pathology Biopsy Service spanning from 1994 to 2015 was performed. Extraoral cases as well as cases with insufficient patient information were excluded. A total of 340 out of 164,578 submitted specimens in a 22 year period (0.2%) were included with a mean age of 43.3 years (range: 6-89), and 44% male and 56% female. The most commonly affected locations were: tongue (37.5%), palate (22%), lip (19%), and gingiva (14%). The microscopic diagnoses rendered, in descending order of frequency were: neurofibromas (NFs): 123 (36%), granular cell tumor (GCT): 108 (32%), schwannomas: 61 (17%), palisaded encapsulated neuromas: 39 (11%), benign neural lesion not otherwise specified: 8 (2%), and mucosal neuroma c/w multiple endocrine neoplasia type 2B (MEN 2B): 1 (< 0.5%). Six cases of NF reported a history of neurofibromatosis Type 1 (NF 1). Four cases showed multifocal lesions. Immunohistochemical staining was performed on equivocal cases (25% of the lesions) and all were confirmed by their S-100 positivity. Intraoral neural neoplasms, though uncommon should be in the differential diagnosis of oral soft tissue entities and specific consideration to syndromal linkage is paramount as this may impact patient management.

Comparative Analysis of Head and Neck and Non–Head and Neck Malignant Peripheral Nerve Sheath Tumors

Objectives

Malignant peripheral nerve sheath tumors (MPNSTs) are a group of tumors that arise from peripheral nerves or from the various elements of the nerve sheath, including Schwann cells and perineural fibroblasts. Head and neck MPNSTs (HN-MPNSTs) are rare, accounting for 8% to 16% of all soft tissue sarcomas. This study analyzes the demographic, clinicopathologic, and survival characteristics of HN-MPNSTs and establishes comparisons with MPNSTs at other body sites (other-MPNSTs).

Study Design

Analysis of population-based tumor registry.

Setting

Academic medical center.

Subjects and Methods

The SEER database (Surveillance, Epidemiology, and End Results; 1973-2012) was queried for HN-MPNSTs (324 cases) and other-MPNSTs (1680 cases). Data were analyzed comparatively with respect to various demographic and clinicopathologic factors. Disease-specific survival was analyzed with the Kaplan-Meier model.

Results

Mean age at diagnosis for HN-MPNST was 49.1 years, compared with 46.1 years for other-MPNSTs ( P = .0169). There was a sex predilection for males in HN-MPNSTs (60.2%) versus a female predilection for other-MPNSTs (54.2%; P < .0001). Average tumor size for HN-MPNSTs was 4.9 cm, compared with 8.7 cm for other-MPNSTs ( P < .0001). HN-MPNSTs were more commonly of low histologic grade types, whereas other-MPNSTs were mostly of high histologic grade ( P = .0073). HN-MPNSTs had a higher 5-year disease-specific survival than other-MPNSTs (65.1% vs 57.4%; P = .0209).

Conclusions

HN-MPNSTs are rare entities. This study represents the largest series of HN-MPNSTs to date. Although HN-MPNSTs and other-MPNSTs share a common histology, there are important clinical differences between the 2 groups.