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 types. Genital types are recognized, but are often part of either the fetal or juvenile types. The fetal type is thought to recapitulate immature skeletal muscle at about week six to ten of gestational development. Signs and symptoms
Most fetal rhabdomyomas are tumors that develop in the head and neck or in the genital region. There are a number of cases which have been seen in association with Gorlin syndrome. However, cardiac myxomas are known to be associated with tuberous sclerosis. Pathophysiology
Gross pathology
The tumor may be seen within the subcutaneous tissues (below the skin), mucosal surfaces or in soft tissue. Within the head and neck, the posterior ear region, skin of the face, and the tongue are the most commonly affected sites (about a 2:1 ratio of soft tissue to mucosa). The tumors are well defined, non-specific usually solitary masses, but when seen in the head and neck (or genital region), they may be polypoid. Tumors range in dimension from a few millimeters up to 12.5 cm, with a mean of about 3.0 cm. Although there are isolated case reports, multifocality is very rare. Microscopic pathology
Fetal rhabdomyoma are separated into two histologic types: Myxoid and cellular. However, irrespective of histologic type, these tumors almost never show necrosis or increased mitoses. However, a cambium layer, abnormal mitoses and nuclear pleomorphism is not seen.
Cluttons joints is a term describing the finding of symmetrical joint swelling seen in patients with congenital syphilis. It most commonly affects the knees, presenting with synovitis and joint effusions (collections of fluid within the joint capsules) lasting up to a year. It has also been reported affecting the ankles, elbows, wrists and fingers. It is usually painless, although pain in the absence of trauma can occur in a few cases. There is usually no disability associated with the joint swelling, and recovery is usually complete. It occurs between 5 and 20 years of age in both sexes.The condition was described in 1886 by Henry Hugh Clutton in The Lancet. == References ==