Gynaecological Perspective of Schwannoma: A Rare Pelvic Tumour

Abstract

Schwannomas are benign tumours that arise from Schwann cells of nerve fibres. They commonly occur in the head, neck, mediastinum and extremities but pelvic occurrence is rare. We report a rare case of retroperitoneal tumour with Gynaec presentation. A 26-year-old parous woman was admitted with abdominal mass, pain abdomen, painful menstruation and painful coitus for one year. Abdominal examination revealed firm mass filling the lower abdomen with restricted mobility. On bimanual examination cervix was hitched against pubic symphysis. Mass felt through anterior and left adnexa not tender, uterus felt close to the mass about 8-10 weeks size, right adnexa free. USG revealed broad ligament fibroid with cystic right ovary. Hence myomectomy was planned, but intraoperatively it was found that the mass was filling the pelvis close to bulky uterus with cystic right ovary. After informed consent while proceeding with hysterectomy, necrotic, yellow colour material came out from the capsule like structure of the mass which was close to lower part of posterior wall of uterus. Mass was removed except which was adherent to deeper structure left behind. Histopathological examination revealed Schwannoma undergoing cystic degeneration. Since Schwannoma was mostly diagnosed incidentally, high degree suspicion is necessary for diagnosis.

Keywords: Benign; Neurogenic; Pelvis.

[Table/Fig-1]:

Intraoperative picture showing the mass (arrow) close to uterus with bilateral ovaries.

[Table/Fig-2]:

Retroperitoneal tumour with the Necrotic yellowish material. (arrow)

[Table/Fig-3]:

Tumour with uterus after surgical removal.

[Table/Fig-4]:

Microscopically, the tumour was highly cellular; ill circumscribed, composed of spindle-shaped cells variably arranged in intersecting long or short fascicles (40X).

[Table/Fig-5]:

Spindle cells had moderate amounts of eosinophilic cytoplasm and wavy nuclei (100X).

[Table/Fig-6]:

Tumour contained numerous small to medium sized blood vessels with thick hyalinized walls (40X).

[Table/Fig-7]:

Areas of degenerative changes characterized by oedema, and abundant foamy histiocytes interspersed among fascicles of tumor cells were noted (100X).

[Table/Fig-8]:

Interestingly, a foci of bone formation composed of bony trabeculae enclosing marrow spaces, was seen (40X).

[Table/Fig-9]:

Immunohistochemistal staining for S100 was performed with mouse Antibody Clone: 4C4.9 S100 (Bio SB). The spindle cells exhibited positivity for S100 (100X).