Enlargement of the Pineal Gland in Hereditary Retinoblastoma May Not Indicate Pineoblastoma

Abstract

Abstract: : Purpose:To describe benign pineal enlargement (pseudopineoblastoma) after chemotherapy for hereditary retinoblastoma and its differentiation from pineoblastoma. Methods: Case report Results:Two patients with hereditary retinoblastoma underwent chemotherapy and on MRI had significant enlargement of the pineal gland. Initially, the MR findings were diagnosed as pineoblastoma. Despite significant growth, the pineal glands were somewhat smaller and more regular in shape and showed a more homogeneous internal signal than most pineoblastomas. Immediate testing with unenhanced CT showed no calcification. Repeat MRI showed no further growth after 2 months and with serial studies for 1 year in both patients. Pineal cysts were seen at 18 and 30 months using the 3 Tesla MRI. Conclusions: Benign enlargement of the pineal gland may occur after chemotherapy for hereditary retinoblastoma. In cases with uncertain diagnosis, additional testing is important in order to avoid confusion of benign enlargement since the treatment of pineoblastoma is associated with significant morbidity.

Keywords: retinoblastoma • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • oncology