Nevoid basal cell carcinoma syndrome
Encyclopedia
Nevoid basal cell carcinoma syndrome (NBCCS), also known as basal cell nevus syndrome, multiple basal cell carcinoma syndrome, Gorlin syndrome, and Gorlin–Goltz syndrome, is an inherited medical condition involving defects within multiple body systems such as the skin
, nervous system
, eyes, endocrine system
, and bone
s. People with this syndrome are particularly prone to developing a common and usually non-life-threatening form of non-melanoma
skin cancer
s.
About 10% of people with the condition do not develop basal cell carcinoma
s (BCCs). the name Gorlin syndrome refers to researcher Robert J. Gorlin
(1923–2006).
First described in 1960, NBCCS is an autosomal dominant condition that can cause unusual facial appearances and a predisposition for basal cell carcinoma
, a malignant type of skin cancer. The prevalence is reported to be 1 case per 56,000-164,000 population. Recent work in molecular genetics
has shown NBCCS to be caused by mutations in the PTCH (Patched
) gene found on chromosome
arm 9q
. If a child inherits the defective gene from either parent, he or she will have the disorder.
s (BCCs) occur each year in the United States. Ultraviolet
(UV) radiation from the sun is the main trigger of these cancers, and people with fair skin are especially at risk. Most sporadic BCCs arise in small numbers on sun-exposed skin of people over age 50, although younger people may also be affected.
By comparison, NBCCS has an incidence of 1 in 50,000 to 150,000 with higher incidence in Australia. One aspect of NBCCS is that basal cell carcinomas will occur on areas of the body which are not generally exposed to sunlight, such as the palms and soles of the feet and lesions may develop at the base of palmar
and plantar pits.
One of the prime features of NBCCS is development of multiple BCCs at an early age, often in the teen years. Each person who has this syndrome is affected to a different degree, some having many more characteristics of the condition than others.
The major criteria consist of the following:
The minor criteria include the following:
People with NBCCS need education about the syndrome, and may need counseling and support, as coping with the multiple BCCs and multiple surgeries is often difficult. They should reduce UV light exposure, to minimize the risk of BCCs. They should also be advised that receiving Radiation therapy
for their skin cancers may be contraindicated. They should look for symptoms referable to other potentially involved systems: the CNS, the genitourinary system, the cardiovascular system, and dentition.
Genetic counseling
is advised for prospective parents, since one parent with NBCCS causes a 50% chance that their child will also be affected.
the condition.
Human skin
The human skin is the outer covering of the body. In humans, it is the largest organ of the integumentary system. The skin has multiple layers of ectodermal tissue and guards the underlying muscles, bones, ligaments and internal organs. Human skin is similar to that of most other mammals,...
, nervous system
Nervous system
The nervous system is an organ system containing a network of specialized cells called neurons that coordinate the actions of an animal and transmit signals between different parts of its body. In most animals the nervous system consists of two parts, central and peripheral. The central nervous...
, eyes, endocrine system
Endocrine system
In physiology, the endocrine system is a system of glands, each of which secretes a type of hormone directly into the bloodstream to regulate the body. The endocrine system is in contrast to the exocrine system, which secretes its chemicals using ducts. It derives from the Greek words "endo"...
, and bone
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
s. People with this syndrome are particularly prone to developing a common and usually non-life-threatening form of non-melanoma
Melanoma
Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...
skin cancer
Skin cancer
Skin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...
s.
About 10% of people with the condition do not develop basal cell carcinoma
Basal cell carcinoma
Basal-cell carcinoma is the most common type of skin cancer. It rarely metastasizes or kills. However, because it can cause significant destruction and disfigurement by invading surrounding tissues, it is still considered malignant. Statistically, approximately 3 out of 10 Caucasians may develop a...
s (BCCs). the name Gorlin syndrome refers to researcher Robert J. Gorlin
Robert J. Gorlin
Robert James Gorlin was a professor and researcher at the University of Minnesota known for pioneering research into craniofacial disorders.Gorlin was born in Hudson, New York on January 11, 1923, and died in Minneapolis, Minnesota on August 29, 2006....
(1923–2006).
First described in 1960, NBCCS is an autosomal dominant condition that can cause unusual facial appearances and a predisposition for basal cell carcinoma
Basal cell carcinoma
Basal-cell carcinoma is the most common type of skin cancer. It rarely metastasizes or kills. However, because it can cause significant destruction and disfigurement by invading surrounding tissues, it is still considered malignant. Statistically, approximately 3 out of 10 Caucasians may develop a...
, a malignant type of skin cancer. The prevalence is reported to be 1 case per 56,000-164,000 population. Recent work in molecular genetics
Molecular genetics
Molecular genetics is the field of biology and genetics that studies the structure and function of genes at a molecular level. The field studies how the genes are transferred from generation to generation. Molecular genetics employs the methods of genetics and molecular biology...
has shown NBCCS to be caused by mutations in the PTCH (Patched
PTCH1
Protein patched homolog 1 is a protein that is the member of the Patched family and in humans is encoded by the PTCH1 gene.- Function :PTCH1 is a member of the patched gene family and is the receptor for sonic hedgehog, a secreted molecule implicated in the formation of embryonic structures and in...
) gene found on chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
arm 9q
Chromosome 9 (human)
125px|rightChromosome 9 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome, as they normally do with all chromosomes...
. If a child inherits the defective gene from either parent, he or she will have the disorder.
Incidence
About 750,000 new cases of sporadic basal cell carcinomaBasal cell carcinoma
Basal-cell carcinoma is the most common type of skin cancer. It rarely metastasizes or kills. However, because it can cause significant destruction and disfigurement by invading surrounding tissues, it is still considered malignant. Statistically, approximately 3 out of 10 Caucasians may develop a...
s (BCCs) occur each year in the United States. Ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
(UV) radiation from the sun is the main trigger of these cancers, and people with fair skin are especially at risk. Most sporadic BCCs arise in small numbers on sun-exposed skin of people over age 50, although younger people may also be affected.
By comparison, NBCCS has an incidence of 1 in 50,000 to 150,000 with higher incidence in Australia. One aspect of NBCCS is that basal cell carcinomas will occur on areas of the body which are not generally exposed to sunlight, such as the palms and soles of the feet and lesions may develop at the base of palmar
Palmar
Palmar may refer to:* a directional anatomical term of location* El Palmar de Troya, a small village near Utrera, in Andalusia, Spain* Palmar Sur , a town the Osa region, Puntarenas province, Costa Rica...
and plantar pits.
One of the prime features of NBCCS is development of multiple BCCs at an early age, often in the teen years. Each person who has this syndrome is affected to a different degree, some having many more characteristics of the condition than others.
Components
Some or all of the following may be seen in someone with Gorlin Syndrome:- Multiple basal cell carcinomas of the skin
- Odontogenic keratocystOdontogenic keratocystA keratocystic odontogenic tumour , abbreviated KCOT, is a rare and benign but locally aggressive developmental cystic neoplasm. It most often affects the posterior mandible....
: Seen in 75% of patients and is the most common finding. There are usually multiple lesions found in the mandible. They occur at a young age (19 yrs average). - Rib and vertebrae anomalies
- Intracranial calcification
- Skeletal abnormalities: bifid ribs, kyphoscoliosis, early calcification of falx cerebri (diagnosed with AP radiograph)
- Distinct faces: frontal and temporopariental bossing, hypertelorism, and mandibular prognathism
Diagnostic criteria
Diagnosis of NBCCS is made by having 2 major criteria or 1 major and 2 minor criteria. http://www.gorlingroup.org/index.php?option=com_content&view=article&id=20:diagnostic-criteria&catid=16:diagnosis&Itemid=4The major criteria consist of the following:
- more than 2 BCCs or 1 BCC in a person younger than 20 years;
- odontogenic keratocystOdontogenic keratocystA keratocystic odontogenic tumour , abbreviated KCOT, is a rare and benign but locally aggressive developmental cystic neoplasm. It most often affects the posterior mandible....
s of the jaw - 3 or more palmar or plantar pits
- ectopic calcificationEctopic calcificationEctopic calcification is a pathologic deposition of calcium salts in tissues. This can be a symptom of hyperphosphatemia.-References:*...
or early (<20 years) calcification of the falx cerebriFalx cerebriThe falx cerebri, also known as the cerebral falx, so named from its sickle-like form, is a strong, arched fold of dura mater which descends vertically in the longitudinal fissure between the cerebral hemispheres.... - bifid, fused, or splayed ribs
- first-degree relative with NBCCS.
The minor criteria include the following:
- macrocephalyMacrocephalyMacrocephaly , occurs when the head is abnormally large; this includes the scalp, the cranial bone, and the contents of the cranium.-Causes:...
. - congenital malformations, such as cleft lip or palateCleftCleft lip and cleft palate , which can also occur together as cleft lip and palate, are variations of a type of clefting congenital deformity caused by abnormal facial development during gestation. A cleft is a fissure or opening—a gap. It is the non-fusion of the body's natural structures that...
, frontal bossing, eye anomaly (cataract, colobma, microphtalmia, nystagmus). - other skeletal abnormalities, such as Sprengel deformity, pectus deformityPectus excavatumPectus excavatum is the most common congenital deformity of the anterior wall of the chest, in which several ribs and the sternum grow abnormally. This produces a caved-in or sunken appearance of the chest...
, polydactyly, syndactylySyndactylySyndactyly is a condition wherein two or more digits are fused together. It occurs normally in some mammals, such as the siamang and kangaroo, but is an unusual condition in humans.-Classification:...
or hypertelorismHypertelorismHypertelorism is an abnormally increased distance between two organs or bodily parts, usually referring to an increased distance between the orbits . In this condition the distance between the inner eye corners as well as the distance between the pupils is greater than normal...
. - radiologic abnormalities, such as bridging of the sella turcicaSella turcica-External links:*...
, vertebral anomalies, modeling defects or flame-shaped lucencies of hands and feet. - ovarian and cardio fibromaFibromaFibromas are benign tumors that are composed of fibrous or connective tissue. They can grow in all organs, arising from mesenchyme tissue. The term "fibroblastic" or "fibromatous" is used to describe tumors of the fibrous connective tissue...
or medulloblastomaMedulloblastomaMedulloblastoma is a highly malignant primary brain tumor that originates in the cerebellum or posterior fossa.Previously, medulloblastomas were thought to represent a subset of primitive neuroectodermal tumor of the posterior fossa...
(the latter is generally found in children below the age of two).
People with NBCCS need education about the syndrome, and may need counseling and support, as coping with the multiple BCCs and multiple surgeries is often difficult. They should reduce UV light exposure, to minimize the risk of BCCs. They should also be advised that receiving Radiation therapy
Radiation therapy
Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...
for their skin cancers may be contraindicated. They should look for symptoms referable to other potentially involved systems: the CNS, the genitourinary system, the cardiovascular system, and dentition.
Genetic counseling
Genetic counseling
Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...
is advised for prospective parents, since one parent with NBCCS causes a 50% chance that their child will also be affected.
Treatment
Treatment is usually supportive treatment, that is, treatment to reduce any symptoms rather than to cureCure
A cure is a completely effective treatment for a disease.The Cure is an English rock band.Cure, or similar, may also refer to:-Film and television:* The Cure , a short film starring Charlie Chaplin...
the condition.
- Enucleation of the odontogenic cysts can help but new lesions, infections and jaw deformity are usually a result.
- The severity of the basal cell carcinoma determines the prognosis for most patients. BCCs rarely cause gross disfigurement, disability or death http://dermatology.cdlib.org/DOJvol6num1/case_reports/bcc/00-1m.html.
- Genetic counseling