The location and appearance of second malignancies in patients with bilateral retinoblastoma

Leiomyosarcoma of the Nasal Cavity and Paranasal Sinuses: A Case Report and Comprehensive Review of the Literature

Sinonasal leiomyosarcoma (LMS) is a rare and aggressive mesenchymal tumor with smooth muscle differentiation. The sinonasal tract is an unusual primary site for LMS, as scant smooth muscle exists in this location, with only 75 cases reported in the English literature including the case presented herein. Sinonasal LMS is considered an aggressive head and neck tumor with significant potential for recurrence and metastasis. Since recurrence is high and the potential for late metastasis exists, lifelong follow-up in these patients would be beneficial, especially among those with previous history of RB.

Nasal sinus leiomyosarcoma in a patient with history of non-hereditary unilateral treated retinoblastoma

Hereditary patients with a history of treated retinoblastoma (RB) have a greatly increased risk of a broad spectrum of secondary malignancies appearing many years later, with a high incidence in the head and neck region. Leiomyosarcomas (LMS) account for up to 58% of these tumors. LMS in the sinonasal region generally are uncommon and are associated with a locally aggressive course and have a poor prognosis. RB may occur in two forms. The hereditary form is generally bilateral but can present unilaterally with a positive family history and typically exhibits a germline mutation in the RB1 gene on chromosome 13. The non-hereditary form is usually unilateral but can show the same germline mutation in up to 10% of cases. Patients with hereditary RB have been shown to have a significantly higher cumulative risk of developing secondary malignancies than those with the non-hereditary form (28 vs. 1.44% respectively). Most reported cases of sinonasal LMS are in patients with a history of the bilateral hereditary form of treated RB. We report a case of LMS of the nasal sinus area in a 35-year-old African American male with a history of non-hereditary unilateral RB and radiation therapy. To the best of our knowledge, this is the first reported case of sinonasal LMS arising in a patient with a history of non-hereditary unilateral RB. The clinical history, radiology, and pathology are presented along with a brief discussion of the literature.