Elevation of the nail bed can occur. In rare cases, the tumors may present in other body areas, such as the gastric antrum or glans penis. Treatment is essentially the same.Malignant glomus tumors, or glomangiosarcomas, are extremely rare and usually represent a locally infiltrative malignancy. However, metastases do occur and are usually fatal. Diagnosis
Cancerous glomus tumors are exceedingly rare. Criteria for the diagnosis of malignancy in glomus tumors are:
Tumor size of more than 2 centimeters and subfascial or visceral location. Atypical mitotic figures. Marked nuclear atypia and any level of mitotic activity. Pericytes of ZimmermanCancerous glomus tumors have been subdivided into three categories based on their histologic appearance: locally infiltrative glomus tumors (LIGT), glomangiosarcomas arising in benign glomus tumors (GABG), and glomangiosarcomas arising de novo (GADN).A few cases of cancerous glomus tumors have been reported; however, they are usually only locally invasive, and metastases are exceedingly rare. There is one report of widespread metastases of a malignant glomus tumor involving the skin, lungs, jejunum, liver, spleen, and lymph nodes. Another report of a malignant glomus tumor (glomangiosarcoma) with metastases from the skin. A malignant glomus tumor one arose from the kidneys. Differential
The probable misdiagnosis of many of these lesions as hemangiomas or venous malformations also makes an accurate assessment of incidence difficult. Treatment
Surgical excision is the preferred treatment for benign glomus tumors. Epidemiology
The exact rate of glomus tumors is unknown. The multiple variant is rare, accounting for less than 10% of all cases.
MORM syndrome is an autosomal recessive congenital disorder characterized by mental retardation, truncal obesity, retinal dystrophy, and micropenis". The disorder shares similar characteristics with Bardet–Biedl syndrome and Cohen syndrome, both of which are autosomal recessive genetic disorders. MORM syndrome can be distinguished from the above disorders because symptoms appear at a young age. The disorder is not dependent on sex of the offspring, both male and female offspring are equally likely to inherit the disorder. The syndrome is caused by a mutation in the INPP5E gene which can be located on chromosome 9 in humans. Further mapping resulted in the identification of a MORM syndrome locus on chromosome 9q34.3 between the genetic markers D9S158 and D9S905. Presentation
For individuals with MORM syndrome, symptoms do not appear until about one year of age. From conception to birth, individuals with MORM syndrome appear asymptotic, with no abnormal characteristics. Vision is negatively affected within the first year of life, particularly night vision. Individuals with MORM syndrome experience decreased visual acuity, meaning their ability to see distinct sharp lines decreases. Vision quality continues to deteriorate until age three. Any further reduction in vision acuity is not observed until the individual is between the ages thirty to forty. Delayed sentence processing and intellectual disability is associated with individuals with MORM syndrome, primarily observed at age four. Individuals continue to develop and grow until they are five to twelve years old.