Human papillomavirus-related multiphenotypic sinonasal carcinoma

Surgical treatment for uncommon malignancies of the paranasal sinuses and anterior cranial fossa: report of two cases and literature review

Malignant tumors of the nasal and paranasal cavities account for only 3-5% of all head and neck neoplasms. Among these tumors, rare instances of human papillomavirus (HPV)-positive multiphenotypic carcinomas and biphenotypic sarcomas have been documented. Two such cases are reported here, along with the respective treatment approaches. The first involved a 39-year-old male patient diagnosed with HPV-positive multiphenotypic carcinoma. Surgical treatment was performed through a craniofacial and transfacial approach, en bloc resection, and reconstruction of the anterior cranial base with a fascia lata graft and pericranial flap. The second involved a 41-year-old female patient diagnosed with biphenotypic sarcoma. Surgical treatment was performed through centripetal endoscopic tumour resection. In both cases, adjuvant radiotherapy was performed after obtaining the histopathological result and negative margins. Both patients were free of disease during postoperative follow-up. Given the rarity of these cases, there are no established guidelines outlining specific treatments. It is recommended that such tumours are assessed in interdisciplinary committees to determine the optimal treatment options. Typically, this will involve surgical resection via craniofacial and transfacial approaches or endoscopic surgery, depending on the diagnosis, extent of anatomical involvement, and tumour aggressiveness. Additionally, the potential benefits of adjuvant radiotherapy should be evaluated, as it has demonstrated promising outcomes, even in cases with positive margins.

HPV-Related Multiphenotypic Sinonasal Carcinoma: A Clinicoradiological Series of 3 Cases With Full Endoscopic Surgical Outcome

Context: Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC), formerly known as HPV-related carcinoma with adenoid cystic like features, is a rare tumor subtype with unusual correlation between radiological, histopathological, and surgical findings. The shared histological characteristics with other sinonasal tumors make the diagnosis challenging. Optimal surgical and oncological treatments for this rare condition remains to be clearly defined. Methods: The objective of the study was to describe the unique characteristics and endoscopic surgical treatment of this rare tumor. In this retrospective case series, all patients with an HMSC diagnosis treated in our tertiary center were selected. Results: Three HMSC cases were identified, including 2 male and 1 female patients. All cases originated from the posterior nasal cavity. One case presented with a tumor of 8.9 cm × 6.4 cm × 8.7 cm, which is the largest tumor volume described to date. All patients received exclusively endoscopic surgical treatment, followed by adjuvant radiation therapy. No patient showed clinical or radiological sign of disease recurrence, or regional or distant metastasis, with a follow-up ranging from 9 months to 4 years. In 2 cases, initial diagnoses incorrectly suggested adenoid cystic or basaloid squamous cell carcinoma. HPV-DNA testing confirmed the presence of HPV in all cases, with identification of strains 16 and 18. Conclusion and Relevance: HMSC represents a newly identified diagnosis that constitutes a significant challenge for both clinicians and pathologists. It is crucial to acknowledge its indolent clinical course and the apparent contradiction between aggressive radiological features and the noninvasive nature of surgical findings. Skull base surgeons should be aware that, despite these complexities, endoscopic treatment is achievable in the majority of cases. This understanding is essential for the effective management of HMSC.

Radiological features of human papillomavirus-related multiphenotypic sinonasal carcinoma: systematic review and case series

PURPOSE

To comprehensively summarize the radiological characteristics of human papillomavirus (HPV)-related multiphenotypic sinonasal carcinomas (HMSCs).

METHODS

We reviewed the findings for patients with HMSCs who underwent computed tomography (CT) and/or magnetic resonance imaging (MRI) and included nine cases from nine publications that were identified through a systematic review and three cases from our institution. Two board-certified radiologists reviewed and evaluated the radiological images.

RESULTS

The locations in almost all cases included the nasal cavity (11/12, 91.7%). The involved paranasal sinuses included the ethmoid sinus (6/12, 50.0%) and maxillary sinus (3/12, 25.0%). The mean long diameter of the tumors was 46.3 mm. The margins in 91.7% (11/12) of the cases were well-defined and smooth. Heterogeneous enhancement on contrast-enhanced CT, heterogeneous high signal intensities on T2-weighted images and heterogeneous enhancement on gadolinium-enhanced T1-weighted images were noted in 2/2, 5/5, and 8/8 cases, respectively. Mean apparent diffusion coefficient values in two cases of our institution were 1.17 and 1.09 × 10^-3 mm²/s. Compressive changes in the surrounding structures were common (75%, 9/12). Few cases showed intraorbital or intracranial extension. None of the cases showed a perineural spread, neck lymph node metastasis, or remote lesions.

CONCLUSIONS

We summarized the CT and MRI findings of HMSCs. Knowledge of such characteristics is expected to facilitate prompt diagnosis and appropriate management.