Recurrent inverted papilloma coexisted with skull base lymphoma: A case report

Background Inverted papilloma is an uncommon neoplasm in the nasal cavity. It is a histologically benign tumor, but has a high recurrence and local invasion rate. In addition, nasal or skull base lymphoma is another rare neoplasm. The coexistence of these two tumors in one case makes the diagnosis and related treatment difficult. Case summary We report a case of an immunocompetent patient, who had a history of inverted papilloma 20 years ago. The patient presented with an infiltrated mass lesion in the nasal cavity with extension to the frontal base. The repeated biopsies revealed inverted papilloma without any malignant transformation. After the patient underwent a frontobasal craniotomy with total tumor excision, the final pathological examination revealed nasal inverted papilloma coexisting with diffuse large B-cell lymphoma of the skull base. Conclusion Based on this case report, while managing a case of an aggressive recurrent inverted papilloma, not only squamous cell carcinoma transformation, but also other invasive malignancy, such as lymphoma, should be considered.