Pelvic rhabdomyosarcoma: a review of the RPMI experience

Perianal rhabdomyosarcoma presenting as a perirectal abscess: A report of 11 cases

BACKGROUND PURPOSE

The organs and soft tissues of the pelvis are some of the most common primary sites for rhabdomyosarcoma (RMS) in children and adolescents. In most cases a mass is detectable on clinical examination, and the initial concern is focused on the possibility of a neoplasm. The current report concerns 11 patients, each presented with a painful perineal-perianal mass suggesting an abscess to the extent that each one of these patients was treated initially with antibiotics or incision and drainage for several weeks to months before the pathologic diagnosis of RMS was established.

METHODS

The authors reviewed the clinical histories of all patients with perirectal/perianal RMS from their respective institutions to identify cases in which the initial clinical diagnosis or impression was that of a perirectal abscess. Pathologic material was reviewed in all cases.

RESULTS

Eleven patients, 7 of whom were girls, ranged in age from 1 to 16 years at diagnosis (median age, 14 years). Fever accompanied the clinical presentation in 2 patients. None of the patients had a past medical history of illness that may have predisposed them to a perirectal abscess, although one patient had a family history of inflammatory bowel disease. Duration of symptoms ranged from 1 month to 1 year (mean, 4.6 months). Each patient presented with a tender perianal/perineal nodule or mass. Inguinal adenopathy was present in 6 patients at diagnosis. White blood cell counts ranged from 6,600/mm(3) to 24,500/mm(3). LDH levels ranged from 414 to 3,432 U/L. The average time from presentation to pathologic diagnosis of RMS was 2.1 months. Nine of the 11 cases showed an alveolar pattern. All were high-stage disease. Of 7 patients with follow-up longer than 1 year, 2 (29%) are alive without disease.

CONCLUSION

This report presents the need to consider the possibility of a malignant neoplasm, in this case RMS, in a child or adolescent with a putative perirectal abscess that fails to respond in the expected manner to incision and drainage and antibiotic therapy.

Prostatic embryonal rhabdomyosarcoma in adults. A clinicopathologic review

Embryonal rhabdomyosarcoma of the prostate is a rare, highly malignant tumor that occurs predominantly in male infants and children, in whom it is the most common prostatic sarcoma. Six cases occurring in adults have been published, and the authors report three additional cases. The natural history is characterized by rapid growth, with the typical formation of large pelvic or abdominal masses, often leading renal failure due to bilateral ureteric obstruction. The tumor eventually disseminates widely, mainly to the lungs, bone, liver, and serosal surfaces, and unlike most other sarcomas, regional lymph node metastases are common. Combined modality therapy has resulted in marked improvement in survival rates and reduced surgical morbidity for children with these tumors. However, in adults the prognosis remains poor, with all patients dying of disseminated disease within 16 months of histologic diagnosis (mean survival, 8 months).