Aged ; Aged, 80 and over ; Carcinoma, Squamous Cell ; chemistry ; pathology ; Female ; Head and Neck Neoplasms ; chemistry ; pathology ; Humans ; Immunohistochemistry

OBJECTIVETo investigate the clinicopathologic characteristics, differential diagnosis and biological behavior of extracardiac rhabdomyoma.

METHODSNine cases of extracardiac rhabdomyoma diagnosed between January of 1997 and July of 2014 were reviewed. The clinical, pathologic and immunohistochemical profiles were evaluated.

RESULTSThere were 5 males and 4 females at diagnosis with age ranging from 2 years and three months to 59 years (mean, 37.6 years). Sites included the head and neck region (7 cases), chest (1 case ) and vagina wall (1 case). Clinically, most cases manifested as a subcutaneous nodule or as a submucosal polypoid lesion with a mean diameter of 3.2 cm. Histologically, 4 were adult-type rhabdomyoma characterized by tightly packed large round or polygonal rhabdomyoblasts with abundant eosinophilic to clear cytoplasm; 3 were myxoid variant of fetal rhabdomyoma composed of immature myofibrils, spindled and primitive mesenchymal cells embedded in a myxoid background, 1 was an intermediate form of fetal rhabdomyoma consisting of densely arranged differentiated myoblasts with little myxoid stroma; 1 was a genital rhabdomyoma composed of elongated or strap-like myoblasts scattered in loose fibrous connective tissue. By immunohistochemistry, they showed diffuse and strong positivity for desmin, MSA and myoglobin with variable expression of myogenin. A case of intermediate type also stained for α-smooth muscle actin. Follow up data (2 months ~ 17 years) showed local recurrence in one patient 6 months after surgery.

CONCLUSIONSRhabdomyoma is a distinctively rare benign mesenchymal tumor showing skeletal muscle differentiation, which may occassionally recur if incompletely excised. Familiarity with its clinical and morphological variants is essential to avoid misdiagnosing this benign lesion as embryonal rhabdomyosarcoma.

Adolescent ; Adult ; Cell Differentiation ; Child ; Child, Preschool ; Desmin ; analysis ; Diagnosis, Differential ; Female ; Head and Neck Neoplasms ; chemistry ; pathology ; Humans ; Immunohistochemistry ; Male ; Mesenchymoma ; pathology ; Middle Aged ; Myogenin ; analysis ; Neoplasm Recurrence, Local ; Rhabdomyoma ; chemistry ; pathology ; Rhabdomyosarcoma, Embryonal ; pathology ; Thoracic Neoplasms ; chemistry ; pathology ; Thoracic Wall ; pathology ; Vaginal Neoplasms ; chemistry ; pathology

This study reviewed 65 cases of polymorphic reticulosis (PR) with respect to clinical and histopathologic bases, and immunohistochemical studies were done using MT1 and UCHL as T-cell markers, MB2 as a B-cell marker and alpha-1-antichymotrypsin as a histiocytic marker. The results obtained were as follows: 1. The male to female ratio was 2.4:1 and the mean age of patients was 44.5 years. The sites involved primarily were the nasal cavity, tonsil and pharynx and about one-fourth of the total cases showed extensive involvement of two anatomical sites at initial presentation. 2. Almost all cases showed characteristic histologic features similar to those of peripheral T-cell lymphoma and showed positive reaction to the T-cell marker. The above immunohistochemical findings suggest strongly that quite a significant portion of PR is in fact T-cell lymphoma.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antigens, Differentiation, T-Lymphocyte/*analysis ; Antigens, Neoplasm/analysis ; Blood Sedimentation ; Comparative Study ; Female ; Head and Neck Neoplasms/chemistry/*pathology ; Human ; Lymphoma, T-Cell/*pathology ; Male ; Middle Age ; Nasopharyngeal Neoplasms/chemistry/pathology ; Neoplasm Proteins/analysis ; Reticuloendotheliosis/metabolism/*pathology ; Support, Non-U.S. Gov't ; Tumor Markers, Biological/analysis

Animals ; Carcinoma, Squamous Cell ; genetics ; Colorectal Neoplasms ; genetics ; metabolism ; Enzyme Activation ; Esophageal Neoplasms ; genetics ; Genome-Wide Association Study ; Head and Neck Neoplasms ; genetics ; Humans ; Neoplasms ; chemically induced ; enzymology ; genetics ; Phosphoinositide Phospholipase C ; chemistry ; genetics ; metabolism ; physiology ; Signal Transduction ; Skin Neoplasms ; chemically induced ; enzymology ; Stomach Neoplasms ; genetics ; Urinary Bladder Neoplasms ; metabolism ; pathology ; ras Proteins ; metabolism