Ovarian mass in a patient with invasive breast carcinoma: A case report of an unexpected diagnosis

Introduction Ovarian steroid cell tumors not otherwise specified (OSCT-NOS) are extremely rare ovarian sex cord stromal tumors, accounting for <0.1 % of all ovarian tumors. In 25 % of cases, they are asymptomatic leading to a delay in diagnosis. We, herein, report a singular case of OSCT-NOS diagnosed incidentally during the spread assessment of an invasive breast carcinoma of no special type (IBC-NOS). To the best of our knowledge, this is the first reported case of co-occurrence of OSCT-NOS and IBC-NOS. We aim to study the clinic-pathological characteristics of this rare tumor. Case presentation A 56-years old postmenopausal female, with no previous medical history, was diagnosed with an invasive IBC-NOS. The tomography performed during the spread assessment of IBC-NOS showed a suspicious mass of the right ovary. Pelvic MRI revealed an ovarian solid T1 isointense and T2 hyperintense mass. The first evoked diagnosis was an ovarian metastasis of the IBC-NOS. The patient underwent bilateral salpingo-oophorectomy. On gross examination, an ovarian solid mass measuring 2,5x2cm, with a firm gray yellowish cut surface was noted. Microscopic examination and immunostaining concluded to OSCT-NOS and ruled out the diagnosis of an ovarian metastasis of IBC-NOS. Conclusion OSCT-NOS are rare neoplasms. Their diagnosis might be challenging especially in absence of hormonal symptoms. A better knowledge of this rare entities would enable early diagnosis.