Imaging predictors for malignant transformation of inverted papilloma

Carol H Yan; Charles C L Tong; Mrudula Penta; Vishal S Patel; James N Palmer; Nithin D Adappa; Jayakar V Nayak; Peter H Hwang; Zara M Patel

doi:10.1002/lary.27582

Imaging predictors for malignant transformation of inverted papilloma

Laryngoscope. 2019 Apr;129(4):777-782. doi: 10.1002/lary.27582. Epub 2018 Dec 4.

Authors

Carol H Yan¹, Charles C L Tong², Mrudula Penta³, Vishal S Patel¹, James N Palmer², Nithin D Adappa², Jayakar V Nayak¹, Peter H Hwang¹, Zara M Patel¹

Affiliations

¹ Department of Otolaryngology-Head and Neck Surgery, Stanford, California.
² Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A.
³ Department of Radiology, Stanford University, Stanford, California.

PMID: 30515841
DOI: 10.1002/lary.27582

Abstract

Objectives/hypothesis: Inverted papillomas (IPs) are benign tumors of the sinonasal tract with a malignant transformation potential. Predicting the transformation propensity of IPs and corresponding risk factors has long been a challenge. In this study, we aimed to use radiographic findings on magnetic resonance imaging (MRI) and computed tomography (CT) to help differentiate IP from IP-transformed squamous cell carcinomas (IP-SCC).

Study design: Retrospective cohort study.

Methods: A retrospective analysis was performed at two institutions comparing IP (n = 76) and IP-SCC (n = 66) tumors, evaluating preoperative radiographic imaging with corresponding surgical pathology reports. The presence of a convoluted cerebriform pattern (CCP) using postcontrast T1-weighted and T2-weighted MRI was evaluated. Using MRI diffusion-weighted imaging (DWI), we calculated the apparent diffusion coefficient (ADC) value of each tumor. We also determined the tumor origin, attachment sites, and presence of bony erosion using CT imaging.

Results: Benign IPs had a higher prevalence of CCP on MRI compared to IP-transformed SCC (P = .0001. The mean value ADC of malignant IP-SCC (ADC_b0,1000 = 1.12 × 10^-3 mm² /s) was significantly lower than that of benign IPs (ADC_b0,1000 = 1.49 × 10^-3 mm² /s, P = .002). IP-SCC tumors were more likely to be have orbital wall attachment (P = .002) and bony erosion (P < .0001) compared to IPs.

Conclusions: Evaluation of CCP and DWI with ADC values on MRI are promising qualitative and quantitative methods to help differentiate benign IP tumors from their transformed malignant counterparts. Malignant IP-SCCs are associated with a loss of CCP and lower ADC values. Findings of orbital wall involvement and bony erosion on CT may also help determine presence of malignancy.

Level of evidence: 4 Laryngoscope, 129:777-782, 2019.

Keywords: Inverted papilloma; computed tomography; magnetic resonance imaging; malignancy; sinonasal cancer; sinus cancer; squamous cell carcinoma.

Publication types

Evaluation Study

MeSH terms

Aged
Carcinoma, Squamous Cell / diagnostic imaging*
Carcinoma, Squamous Cell / pathology
Cell Transformation, Neoplastic
Diagnosis, Differential
Diffusion Magnetic Resonance Imaging / statistics & numerical data*
Female
Humans
Male
Middle Aged
Nasal Cavity / diagnostic imaging
Nasal Cavity / pathology
Nose Neoplasms / diagnostic imaging*
Nose Neoplasms / pathology
Papilloma, Inverted / diagnostic imaging*
Papilloma, Inverted / pathology
Predictive Value of Tests
Retrospective Studies
Risk Assessment / methods
Risk Factors
Tomography, X-Ray Computed / statistics & numerical data*