An inflammatory polyp with marked stromal atypia (or a low grade malignant fibrous histiocytoma) of the nasal cavity: A report of a case with literature review

Both choanal inflammatory polyp with marked stromal atypia (IPSA) and malignant fibrous histiocytoma (MFH) of the paranasal region are extremely rare lesions. We present a case of recurrent choanal polyposis with marked stromal cell atypia, followed-up longer than any of the reported IPSA and MFH cases in the literature. The lesion was initially thought to be compatible with IPSA. However, because of the development of deep invasion 9 years after the initial presentation, which otherwise had all the described features of IPSA, the diagnosis of a low-grade MFH is considered. The literature on both lesions was reviewed with special emphasis on the biological behavior, such as the recurrence rate, local invasion and distant metastases