Malignant psoas syndrome associated with gynecological malignancy: Three case reports and a review of the literature

Malignant psoas syndrome (MPS) is a rare and unique cancer-associated syndrome caused by the malignant involvement of the psoas major muscle, and is characterized by ipsilateral lumbosacral plexopathy and painful hip flexion. The pain in MPS is often distressing and intractable, and there is no established effective treatment approach. Herein, the present study reports on three cases of MPS associated with gynecological malignancies, wherein symptom improvement was observed following chemotherapy or radiotherapy. Among 39 cases documented in the literature, female genital tract malignancies were the most frequent causes of MPS; however, the condition may be under-diagnosed, owing to the lack of general recognition. Considering the development of recent high-precision radiation therapy, palliative radiotherapy may serve an important role in the management of MPS. For physicians treating gynecological cancers, early detection of MPS is clinically important as this may allow patients to receive possible therapies and improve their quality of life in end-stage cancer. Further prospective studies should be performed to evaluate effective therapeutic approaches for MPS.