Basal cell nevus syndrome is an inherited condition that features the early onset of basal cell cancer in adolescent or young adulthood. This affects several parts of the body with increased risk of developing cancerous and non-cancerous tumors. This usually occurs in the face, chest and the back. The common features of this condition include the multiple basal skin cancers and jaw cysts. However, the features and the severity of the condition can vary greatly among the affected individuals.
Causes
Basal cell nevus syndrome is inherited in an autosomal dominant manner meaning a single defective gene from the parents can cause this condition. In most of these cases, the affected individual inherits the mutated gene, while the other cases have no evidence of its prevalence in the family suggesting a new spontaneous mutation. The gene PTCH1 is responsible for ensuring the cells in the body do not proliferate rapidly. When the mutation of this gene occurs, it affects the normal growth and cell division process. As a result, the body is unable to prevent the development of various types of cancer.
Symptoms
Some of the individuals affected with this condition may not develop any basal cell carcinomas, while the others may be presented with hundreds of these cancers. In addition, the other features include large sized head, depressions in the palms of the hands and soles of the feet, skin cysts, a protruding jaw, spinal abnormalities, wide spaced eyes, anomaly of the ribs and skull. The noncancerous tumors of the jaw known as keratocystic odontogenic tumors may also develop causing infections, pain, swelling and problems with the bone. On some occasions, this can displace their teeth. These affected individuals are at higher risk of developing other forms of cancers which include a brain tumor called medulloblastoma during childhood, ovarian cancer and heart fibromas that affect the blood flow.
Diagnosis
The diagnosis is based on the evaluations of the individual’s history and the physical findings of features associated with this condition that can include abnormalities of the spine, keratocystic odontogenic tumors or fluid on the brain that causes head swelling. In addition, other tests can include an echocardiogram, MRI of the head, x-ray of the head and jaw. A genetic molecular testing can confirm the diagnosis with the presence of the mutated gene responsible for this condition.
Treatment
The first indication of basal cell nevus syndrome is the medulloblastomas in children aged 2 to 5, although this is uncommon. However, the early detection can be treated with surgery or chemotherapy. Most cases require a surgical removal of the jaw tumor. The dermatologist can treat the basal cell carcinomas when detected early, hence these individuals are advised to have regular skin examinations. Sun protection is essential to decrease the risk of developing cancer from sun exposure; however, these individuals cannot entirely prevent the onset of all basal cell carcinomas.
References
http://www.dermnetnz.org/topics/basal-cell-naevus-syndrome/
http://www.cancer.net/cancer-types/nevoid-basal-cell-carcinoma-syndrome
https://ghr.nlm.nih.gov/condition/gorlin-syndrome#diagnosis
