Long-Term Follow-Up of Tamoxifen Treatment and the Use of Imaging in Psammocarcinoma: A Case Report, Review of the Literature and Discussion of Diagnostic and Therapeutic Challenges.

Psammocarcinoma (PsC) represents a rare form of low-grade serous tumor of the ovary or peritoneum. Although ovarian cancer generally has a poor prognosis in its late stages, PsC seems to have a more indolent course. We present a patient with a history of unspecific abdominal pain for more than a year, with sudden acute onset of severe inguinal pain. On admission to the hospital, a computed tomography (CT) revealed a pelvic mass of suspected ovarian origin. Radical surgery was attempted but not achieved due to widespread tumor growth. Histopathological evaluation revealed estrogen receptor-positive stage III PsC. Tamoxifen treatment was thus initiated, still maintaining stable disease 10 years later. The patient has undergone extensive radiological work-up, including CT, chest X-ray, 18F-fluoro-deoxy-glucose positron emission tomography (PET)/CT, 99mTc- hydroxymethylene diphosphonate (HDP) bone scintigraphy, 18F-fluoro-thymidine (FLT) PET/CT, Tc-99m depreotide scintigraphy and magnetic resonance imaging. In conclusion, we demonstrate that PsC has characteristic radiological features and different imaging modalities can be suitable in different clinical situations. In contrast to most other ovarian cancers, PsC does not always warrant adjuvant chemotherapy, even in advanced stages. This emphasizes the need for a deeper knowledge of the biological behavior of this rare tumor, to select the optimal treatment strategy.