A rhabdomyoma is a

benign Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous benign tumor, ''benign'' tumor in that a malign ...

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

striated muscle Striations means a series of ridges, furrows or linear marks, and is used in several ways: * Glacial striation * Striation (fatigue), in material * Striation (geology), a ''striation'' as a result of a geological fault * Striation Valley, in Ant ...

. Rhabdomyomas may be either "cardiac" or "extra cardiac" (occurring outside the heart). Extracardiac forms of rhabdomyoma are sub classified into three distinct types: adult type, fetal type, and genital type. Cardiac rhabdomyomas are the most common primary tumor of the heart in infants and children. It has an association with

tuberous sclerosis Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that causes non-cancerous tumours to grow in the brain and on other vital organs such as the kidneys, heart, liver, eyes, lungs and skin. A combination ...

. In those with tuberous sclerosis, the tumor may regress and disappear completely, or remain consistent in size. A common histological feature is the presence of Spider Cells, which are cardiac myocytes with enlarged glycogen vacuoles separated by eosinophilic strands, resembling the legs of a spider. It is most commonly associated with the

tongue The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surfa ...

, and

heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...

, but can also occur in other locations, such as the

vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

Malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

skeletal muscle tumors are referred to as

rhabdomyosarcoma Rhabdomyosarcoma (RMS) is a highly aggressive form of cancer that develops from mesenchymal cells that have failed to fully differentiate into myocytes of skeletal muscle. Cells of the tumor are identified as rhabdomyoblasts. There are four subt ...

. Only rare cases of possible malignant change have been reported in

fetal rhabdomyoma Rhabdomyoma is a benign mesenchymal tumor of skeletal muscle, separated into two major categories based on site: Cardiac and extracardiac. They are further separated by histology: fetal (myxoid and cellular), juvenile (intermediate), and adult typ ...

. The differential diagnosis in the tongue includes

ectomesenchymal chondromyxoid tumor Ectomesenchymal chondromyxoid tumor (ECT) is a benign intraoral tumor with presumed origin from undifferentiated (ecto)mesenchymal cells. There are some who think it is a myoepithelial tumor type. Controversies about origin * Derived from ectome ...

Additional images

Fetal intermediate cellular type rhabdomyoma

References

Benign neoplasms Heart neoplasia Oral neoplasia Pediatrics {{oncology-stub