Malignancies masquarading as psoas abscesses: An unusual presentation in a developing country

Abstract

19675 Background: Psoas abscess is regarded as a rare disease in medical literature, more so as primary presentation of malignancy or its recurrence. We describe a series of 10 cancer patients who presented with psoas abscess seen in a 18 month period at a large tertiary care cancer hospital in northern India. They were subsequently diagnosed as having malignancy or recurrence of a past malignancy. Methods: A retrospective study of cancer patients who presented with psoas abscess was undertaken. We reviewed clinical data from patients who presented in the period from April 2005 to December 2006 at the Patel Cancer & Superspeciality hospital, Jalandhar, India. Results: In this period 10 cases of cancer met the diagnosis of psoas abscess at presentation. The average age was 51 years (range 20 to 85) with a male female ratio of 4:1. In 7 patients psoas abscess was the presentation at initial diagnosis while in 3 patients it was the presentation of recurrence/relapse. None of the patients had any predisposing conditions like IV drug use, diabetes mellitus, hematoma or HIV positivity.. Majority (7/10) of primary tumors were genito- urinary cancers (Renal - 2, Ureter - 1, Cervix - 1, Prostate - 1, Dysgerminoma - 1, Penis-1) while 3 were of unknown origin. Squamous cell carcinoma was the commonest histology (4/10), followed by metastatic adenocarcinoma (3/10). Majority of the abscess were left sided (7/10) corresponding to the side of primary lesion. Under lying destruction of iliac bone with metastasis was found in only 2 patients. Most of the patients (9/10) responded poorly to treatment ie chemotherapy and radiotherapy, all of them dying of disease progression within a year. Conclusions: Psoas abscess can be a rare presentation of intra abdominal malignancy. Pre disposing factors may not necessarily be present. Genito-urinary malignancies should be kept in the differential diagnosis of unexplained psoas abscesses. Development of psoas abscess does not always signify metastatic disease but portends a poor prognosis to treatment. No significant financial relationships to disclose.