Pathologic collision of inverted papilloma with esthesioneuroblastoma

Sinonasal inverted papilloma associated with small cell neuroendocrine carcinoma: A case report and literature review of rare malignancies associated with inverted papilloma

We report a rare case of sinonasal inverted papilloma (IP) associated with small cell neuroendocrine carcinoma (SNEC). To our knowledge, this is the first report to describe SNEC found during the treatment of sinonasal IP. Surgery and five cycles of cisplatin plus etoposide with concurrent intensity modulated radiation therapy were performed. Neither local recurrence nor distant metastasis was noted during 6 years of post-diagnostic follow-up. The prognosis of SNEC is very poor. Treatment planning for sinonasal IP should consider a possible association with this rare but aggressive malignancy, whose treatment is completely different from that of squamous cell carcinoma, a malignancy which is commonly associated with IP. We also performed a PubMed review of the literature to identify the incidence and pathological diagnosis of associated malignancy. Among a total of 5286 cases of sinonasal IP (61 studies), the incidence of associated malignancy was 8.02% in squamous cell carcinoma, 0.19% in transitional cell carcinoma, 0.04% in mucoepidermoid carcinoma, 0.02% in verrucous cell carcinoma and 0.02% in adenocarcinoma. The incidence of associated malignancy was significantly higher in East and Southeast Asia (11.0%) and North America (10.4%) than in Europe (3.9%) (p=0.04 and p=0.03, respectively; T-test).

Whole-Exome Sequencing of Sinonasal Small Cell Carcinoma Arising within a Papillary Schneiderian Carcinoma In Situ

OBJECTIVE

The pathogenetic underpinnings of extrapulmonary small cell carcinomas (EPSCCs) of the head and neck are poorly understood. We sought to describe the clinical case and whole-exome DNA sequencing data of a patient with sinonasal Schneiderian carcinoma in situ whose tumor progressed to small cell carcinoma (SCC).

STUDY DESIGN

Case report and whole-exome sequencing of tumor DNA.

SETTING

Academic medical center.

SUBJECTS AND METHODS

A 52-year-old man with sinonasal Schneiderian carcinoma in situ whose tumor progressed to small cell carcinoma. We performed whole-exome genetic sequencing and copy-number variation (CNV) analysis of tumor and normal DNA extracted from flash-frozen, paraffin-embedded (FFPE) samples.

RESULTS

A total of 93 high-confidence, nonsynonymous somatic mutation events were identified in sinonasal SCC, including loss-of-function mutations in TP53, MAML3, a transcriptional coactivator of the Notch pathway, and GAS6, an activating ligand of the TAM family of tyrosine kinase receptors. Focal amplifications of chromosomal regions 6p25-11.1, containing SOX4 and VEGFA, and 14q32.1-32.3, containing AKT1 and the Notch inhibitory ligand DLK1, were also seen. Further CNV analysis revealed deletions in the critical cell cycle regulators CDKN2A, RB1, RBL1, and RBL2 and the chromatin modifier EP300.

CONCLUSIONS

Small cell carcinoma may rarely arise from sinonasal Schneiderian carcinoma in situ and exhibits similar genomic aberrations (eg, SOX amplification, Notch pathway inactivation) to pulmonary small cell carcinoma.

Advances in recurrence and malignant transformation of sinonasal inverted papillomas

Sinonasal inverted papilloma (SIP) is a benign tumor of the nasal cavity and sinus. SIP is characterized by aggressive malignant transformation and a high rate of recurrence. Inadequate removal of the tumor during surgery is one of the most significant contributors to SIP recurrence. A growing body of evidence suggests that molecular alteration in SIP, including human papilloma virus infections, single nucleotide polymorphisms of key genes, deregulation of signaling pathways and immunological changes, may lead to SIP occurrence and malignant transformation. However, the extent to which these molecular mechanisms contribute to SIP pathology and transformation remains unclear due to limited research. Further studies are warranted to elucidate the primary dependent factors that contribute to SIP etiology. The present article reviewed risk factors of progression and recurrence of SIP, including outdoor and industrial occupational exposure, smoking, septal deviation, SIP location, recurrent cases, stage of SIP-associated squamous cell carcinoma and choice of surgical method.

Inability of PET/CT to identify a primary sinonasal inverted papilloma with squamous cell carcinoma in a patient with a submandibular lymph node metastasis: A case report

The present study describes the first reported case of a sinonasal inverted papilloma (IP) with squamous cell carcinoma (SCC) that presented as a cancer of unknown primary in the English-language literature. In July 2010, a 66-year old male presented with a 6-month history of a painless, progressive mass in the right submandibular region. Physical examination revealed a 3×4-cm smooth, non-tender mass and subsequently, excision of the right submandibular gland was performed. Post-operative pathological examination indicated poorly-differentiated SCC of the submandibular lymph node. Positron-emission tomography/computed tomography (PET/CT) was unable to identify the primary tumour site in this case, and 14 months later the patient presented with nasal obstruction, leading to the diagnosis of right sinonasal IP with coexistent SCC. The patient received pre-operative radiotherapy, a right total maxillectomy and post-operative radiotherapy. However, the patient succumbed to a distant metastasis 37 months after the initial presentation. ¹⁸F-fluorodeoxyglucose uptake on PET/CT may be not a reliable predictor of malignancy in sinonasal IPs. Therefore, we suggest emphasis of the use of multiple biopsies for suspected sinonasal IPs in order to improve diagnostic accuracy.