Muscle psoas metastasis from uterine squamous cell carcinoma

Abstract

Muscle psoas metastasis from uterine squamous cell carcinomaIntramuscular metastases distant from primary tumour are rare (1%), some authors have reported 16% in autopsied cases. 1 There have been many suggestions for the rarity of neoplastic cells implanted in skeletal muscle, such as constant movement, lactic acid production and lymphocytes, natural killer cells and peptidic factors/protease inhibitors.The affected muscles are psoas, iliopsoas, proximal musculature of the upper and lower limbs and paraspinal muscles. Tumours known to metastasize more frequently to the muscle are melanomas and kidney, lung and thyroid cancers.We report a 29-year-old European patient, who underwent Wertheim-Meigs-Novak radical hysterectomy in July 2005 for moderately differentiated squamous cell carcinoma of uterine portio. The International Federation of Gynecology and Obstetrics stage was III. She underwent 5 weeks of adjuvant external radiotherapy with cisplatin. She was admitted to our unit in December 2006 for a left leg pain that irradiated anteriorly on the muscle quadricipitis femoris and was resistant to drugs. Ultrasound, magnetic resonance imaging and computed tomography scan showed a ovalar lesion (4.5 cm · 7 cm) involving the left psoas muscle (Fig. 1), causing a medial dislocation of the ureter with homolateral hydronephrosis and a dislocation of common iliac artery. Fine-needle aspiration showed metastasis from squamous cell carcinoma. Complete removal of the left psoas muscle, including the lesion, and left ovariectomy were carried out. Metastasis of portio uterine squamous cells carcinoma was confirmed by histopathological examination, pT1b2N1M0, ANZ J. Surg. 2008; 78: 213-219