A 48-year-old man who had previously experienced a seminoma 25 years earlier, came to our attention with a left kidney mass and some masses in the right side of the neck and base of the skull. Before the pathologic examination was completed, the patient and his family did not inform the healthcare professionals about his history of seminoma also there were no records regarding the stage or treatment of seminoma. unfortunately, the patient passed away one month after receiving a diagnosis of metastatic seminoma.

After undergoing multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI), the patient showed some mass-like lesions at the base of the skull and in the right cervical region that also included lymph nodes. Prior to a pathologic examination, radiologic findings pointed to several potential diagnoses, such as lymphoma or kidney-originated tumors that had metastasis to the base of the skull and neck.

Radiologic findings include:

Temporal bone M.D.C.T scan showed Soft tissue density in the middle ear cavity and mastoid antrum in the Rt side, tissue mass lesion in the base of the skull in the Rt side at the foramen jugular region with the destruction of the adjacent bony structure also retention cyst in the sphenoid sinus.

Brain M.D.C.T scan showed a heterogeneous mass lesion in Rt Petrus apical portion reaching the level of the nasopharynx and Post-surgical changes at Rt mastoidectomy, soft-tissue edema, and emphysema in Rt temporal region.

Brain MRI with multiplanar images in different pulse sequences was performed. Diffuse signal changes can be seen in the right side of the skull base, including the petrous apex, right side of the clivus, and C1 vertebra, with intermediate signal intensity on T1W and T2W sequences. Diffusion restriction and enhancement are also seen, extending to the ipsilateral jugular foramen and carotid canal as well as invading the Dorellos canal abducens nerve.

Histologic and immunohistologic findings include:

Seminomas have a nest-like or sheet-like growth pattern, distinct cell membranes, big polygonal nuclei, pale to clear eosinophilic cytoplasm, and nest-like or sheet-like shape in the histological inspection. Lymphocytes could make up the septa. In some metastatic situations, the histological morphology is a little out of the ordinary. Additionally, germ cell characteristics of primary and metastatic seminoma tumors, such as the positivity of the tumor markers OCT3/4, CD117, and PLAP, are similar. ⁹

The neoplastic proliferation of malignant tumoral cells is visible as diffuse patterns in the left kidney mass core needle biopsy (Fig.1). These cells range in size from medium to big, with a high N/C ratio, eosinophilic cytoplasm, and hyperchromic nuclei that are rounded. There are mitotic figures and necrotic tissues. Vimentin, PLAP, CD117, and CD10 IHC staining are all positive in tumor cells (Fig.2).