Rhabdomyosarcoma

INTRODUCTION: We report a rare case of testicular rhabdomyosarcoma with endobronchial metastases in a 14-year old male who presented with shortness of breath and fatigue. Multiple nodular densities were seen on chest x-ray (CXR), with chest CT showing multiple metastatic lesions.

CASE PRESENTATION: A 14-year-old-male presented with a 6-month history of persistent asthma-like symptoms ana easy fatiguability, despite treatment with appropriate anti-asthma medications. On admission, he was tachypneic (35/min), with intercostal retractions. There was no cyanosis or significant lymphadenopathy. The chest was dull on percussion. Breath sound intensity was generally diminished; there were no adventitious sounds. There was no hepato-splenomegaly or ascites. Chest radiograph (CXR) and chest CT showed multiple nodular lesions, with the largest measuring approximately 3 cm. A thorough physical examination revealed a swollen right testicle, which the patient had first noticed 6 months earlier; he was reluctant to disclose this information to anyone. Initial work-up (complete blood and differential count, urea, creatinine, glucose, serum electrolytes, sedimentation rate, liver enzymes, bilirubin, alkaline phosphatase, urinalysis and protein electrophoresis) was normal. Capillary blood gas result showed pH: 7.43, pCO2: 35, HCO3: 25. Human Chorionic Gonadotropin and [alpha]-fetoprotein levels were normal. Lactate dehydrogenase (LDH) was elevated (962-IU/L). Sputum specimen was negative for malignant cells. A combined restrictive-obstructive pattern was evident on pulmonary function testing (body plethysmography). Enlarged mesenteric and retroperitoneal lymph nodes were seen on abdomino-pelvic CT scan. A cystic and solid mass measuring 4.4 x 4.4 cm arose from within the right testis with infiltration into the adjacent epididymis and spermatic cord and extension into the right inguinal canal. Biopsy of the testicular mass revealed embryonal rhabdomyosarcoma. His bone scan was abnormal and bone marrow aspirate showed infiltration and abnormal cells. He was classified as having Stage 3C (metastasis above the diaphragm) testicular cancer. After orchiectomy, the Oncology service began chemotherapy with alternating cycles of Ifosfamide and Etoposide with Vincristine, Actinomycin and Cyclophosphamide followed by Radiotherapy. Ten months into therapy, his repeat CXR and chest CT showed marked improvement; his bone marrow findings, LDH (196-IU/L) and lung function were normal.

DISCUSSIONS: When a child presents with discrete lung masses, apart from the more common differential diagnoses (infectious and immunologic causes), neoplasms (benign, malignant or metastatic) must also be considered. Majority of malignant lung lesions in children are metastatic, so it becomes essential to search for a primary site. Testicular tumors constitute a very small percentage of all malignant tumors in men, and account for 11.4% of deaths from cancer in males between 20-35 years old. Trauma, cryptochordism, and exogenous maternal estrogen (in utero) have 'all been associated with its development. The most common presentation is pain, swelling or hardness of the testis. A few patients may already have signs or symptoms of metastatic disease such as back pain, cough and dyspnea (indicating pulmonary metastasis), nausea and vomiting, bone pain, or central nervous system manifestations. Diagnosis is made by CT scans, serum tumor markers and surgical biopsy. Orchiectomy followed by chemotherapy and/or radiation is the treatment of choice for nonseminomatous tumors. Recurrence may occur within 2 years so intensive surveillance and follow up is necessary. Overall survival rate for this patient's disease stage is 48% at 5-years.

CONCLUSION: 1. This is the first reported pediatric case of embryonal rhabdomyosarcoma with metastasis to bone marrow and lung (Stage 3C). 2. When respiratory symptoms in a child do not respond to treatment, and discrete lung masses are seen on CXR, a thorough clinical history and physical examination is essential for diagnosis. 3. Most young males are unaware of testicular cancer, a highly curable neoplasm that can be detected by self-examination.

DISCLOSURE: Saleh Alharbi, None.

Saleh Alharbi MD * Raquel Consunji-Araneta MD Faisal Almohammadi MD University of Manitoba, Winnipeg, MB, Canada

COPYRIGHT 2005 American College of Chest Physicians
COPYRIGHT 2005 Gale Group