Rhabdomyosarcoma of the Bladder

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Rhabdomyosarcoma accounts for 15% of all pediatric solid tumors. Of these, 20% arise in the urogenital tract, with most frequent localization in the prostate, bladder and paratesticular; rare locations are uterus and vagina. See also section sarcoma of the prostate for pathology and etiology.

Signs and Symptoms of Bladder Sarcoma

Subvesical obstruction with lower urinary tract symptoms, hematuria, urinary retention, disturbed defecation, abdominal pain and palpable lower abdominal tumor.

Diagnostic Work-Up of Bladder Sarcoma

• Cystoscopy, TURB
• TRUS with prostate biopsy
• Computed tomography or better MRI from the abdomen and pelvis
• Chest x-ray
• Bone scan

Treatment of Rhabdomyosarcoma of the Bladder

Therapy should be carried out within clinical trials to improve treatment of this rare disease. After diagnosis, the patients are stratified to an appropriate study protocol in relation the the tumor stage and risk group. The following factors are considered: tumor location, tumor size, histology, grading, lymph node involvement, metastases, and results of surgical treatment. Study protocolls are available at e.g. Children's Oncology Group (COG), which is the successor of the Intergroup Rhabdomyosarcoma Study Group (IRSG).

The goal of rhabdomyosarcoma treatment is healing and preserving a functional lower urinary tract. A tumor resection is performed when the bladder can be spared (partial cystectomy). Since the most common tumor sites are the trigone and the prostate, primary bladder-sparing surgery is not possible. This group of patients will receive a neoadjuvant treatment with chemotherapy and possibly radiation. The subsequent operation can be performed in a bladder-preserving technique in over half of the cases. Effective chemotherapeutic agents are vincristine, actinomycin D, cyclophosphamide, adriamycin, etoposide and ifosfamide, which are used in various combinations. The role of neoadjuvant radiation is controversial, because the resection of the tumor and reconstruction of the urinary tract becomes more difficult (Filipas et al, 2004). Also controversial is the technique of urinary diversion after cystectomy. Some authors advocate a transient incontinent urinary diversion until the oncological risk can be finally assessed and re-operations are unlikely. Others advocate continent urinary diversion with the primary tumor resection, this should be limited to situations with a good prognosis.

Prognosis of Rhabdomyosarcoma of the Bladder

The following clinical factors determine the prognosis: local tumor extension, tumor size, lymph node involvement, distant metastasis and the histological subtype. A goog prognosis (survival) depends critically on the response of neoadjuvant chemotherapy and complete surgical resection. Long-term survival is possible in 50–60% of the cases. In the further course after successful treatment, there is a risk for tumor recurrences, development of contracted bladders after irradiation and complications of urinary diversion.