SPECTRUM OF RHABDOMYOSARCOMA–A STUDY OF 53 CASES AT ARMED FORCES INSTITUTE OF PATHOLOGY, RAWALPINDI (PAKISTAN)

Spectrum of Rhabdomyosarcoma

Abstract

Objective: To study the spectrum of rhabdomyosarcoma, diagnosed at Armed Forces Institute of Pathology (AFIP), Rawalpindi (Pakistan).
Study Design: Descriptive study.
Place and Duration of Study: AFIP, Rawalpindi from 1st Jan 2009 to 31st Dec 2013.
Material and Methods: The study included all the cases diagnosed as rhabdomyosarcoma from 1st January 2009 to 31st Dec 2013. Records of the malignant tumors of soft tissue that presented during this period were analyzed and out of these spectrums rhabdomyosarcoma was studied. The data analysis included the age, gender, site of tumor and histopathological pattern of Rhabdomyosarcoma.
Results: A total of 19140 malignant tumors were diagnosed at AFIP Rawalpindi from 1st Jan 2009 to 31st Dec 2013. Out of these, 512 (2.67%) were malignant soft tissue tumors. Out of these 53 cases were rhabdomyosarcoma with an overall frequency of 0.27% of the malignant neoplasm and 10.3% of soft tissue sarcomas. The age ranged from 1–70 years. Out of these 53 cases 36 were males and 17 were females with a male to female ratio of 2.1:1. The most common subtype of tumor seen was embryonal rhabdomyosarcoma n=22 (41.5%). The age for embryonal rhabdomyosarcoma ranged from 3 to 71 years with median age of 16 years while most of the patients are effected during 1st decade of life (55%). Out of 20 cases of rhabdomyosarcoma during the first two decades of life 18 (90%) were embryonal rhabdomyosacoma. Thirty cases of rhabdomyosarcoma encountered during the adult life contained only 4 cases (11%) of embryonal rhabdomyosarcoma. The majority of the tumors originated from lower extremities (41%) and in lower extremities most common site was thigh (27%). A total of 18% of the tumors originated in head and neck region. Second most common type of the tumor was pleomorphic rhabdomyosarcoma n=21 (39.6%) with age range 40 to 78 years and median age of 60 years. Ten cases were reported during 6th and 7th decade of life. Majority of the cases occurred in lower extremities (47.6%) and thigh was the most common site (42%). Alveolar rhabdomyosarcoma n=6 (11.32%) was the 3rd most common tumor with age range of 15 to 46 years and median age of 29 years. Four cases (67%) occurred in 3rd and 4th decades of life. The most commonly involved region was lower extremities (50%) followed by upper extremities (17%). Among lower extremities again thigh was the most common site (33%). Anaplastic rhabdomyosarcoma n=4 (7.54%) was the least common type of rhabdomyosarcoma with age range of 12 to 45 years and median age of 31 years. Three cases (75%) occurred in the 3rd and 4th decade of life. Two cases (50%) occurred in lower extremities and one case (25%) in the upper extremity.
Conclusion: Embryonal rhabdomyosarcoma is the most common rhabdomyosarcoma during the first two decades of life. While pleomorphic rhabdomyosarcoma is the most common rhabdomyosarcoma encountered in adults. Extremities are most common site of involvement by rhabdomyosarcoma followed by the head and neck and abdomen in our setup. This finding needs to be evaluated by a larger scale study.