Malignant tumors of the seminal vesicles are rare; they may be of epithelial or mesenchymal origin. Carcinomas are the most common and pelvic sarcoma may be confused with a primary tumor of the seminal vesicles. Little is known of the prognosis and best sequence of treatment in such sarcoma. We report a rare case of extra-skeletal Ewing sarcoma/primitive neuroectodermal tumor of the seminal vesicles in a 54-year-old man who presented with chronic lower abdominal pain, urinary retention, and severe constipation. Pelvic CT scan and MRI confirmed the presence of a soft tissue mass lesion centered on seminal vesicles. A trans-gluteal Tru-cut biopsy confirmed the diagnosis. Three cycles of the preoperative chemotherapy VAC/IE (vincristine, Adriamycin and cyclophosphamide, followed by ifosfamide and etoposide) protocol achieved an excellent clinical response.

We present a case of neglected atypical high grade prostatic stromal sarcoma (PSS) at the transitional zone , invading the peripheral zone, prostatic capsule & peri prostatic fat reaching to pelvic side wall, it showed T2WI hyperintense signal (compared to typical cases of PSS showing T2WI hypointense signal) corresponding to developing on top of pre-existing nodular hyperplasia. Careful reviewing of prostatic central / transitional zone lesions is mandatory especially at T2WI, diffusion & contrast images to exclude malignancy which can be easily missed due to multiple signal patterns described. Most common tumors at transitional zone is stromal sarcoma which could be typical showing T2 hypointense signal or atypical showing T2 hyperintense signal intensity.