Gardner syndrome

Gardner syndrome (also known as polyposis coli and multiple hard and soft tissue tumors) is a rare congenital genetically determined disorder. It is directly associated with the development of certain malignancies — particularly colorectal carcinoma—and therefore awareness of this syndrome is important. Gardner syndrome can be considered a form of familial adenomatous polyposis (FAP).

Individuals with this condition also have an increased risk of other tumors, including those of the pancreas, thyroid gland, central nervous system, liver, biliary tract, adrenal glands, and small intestine. In some patients, abnormalities of the teeth and bones may occur, such as osteomas, or benign soft tissue tumors such as epidermoid cysts, fibromas, or lipomas.

Causes

The cause is a mutation in the APC gene, which is a tumor suppressor gene. The functions of the APC gene are diverse; in simplified terms, its normal role is to regulate cell division and prevent tumor formation. Mutations in this gene are not uncommon and are responsible for other conditions in addition to Gardner syndrome.

The inheritance pattern is autosomal dominant, meaning that inheritance of a single mutated gene from one parent is sufficient for the disease to manifest.

Note:
A mutation in the APC gene is also responsible for the more common condition known as familial adenomatous polyposis (FAP). FAP is also characterized by the presence of polyps in the colon, but it lacks the extraintestinal manifestations typical of Gardner syndrome. From another perspective, Gardner syndrome can be regarded as a variant of FAP with additional features.

Diagnosis

The diagnosis is based on the presence of the clinical features, especially multiple colonic polyps. Definitive confirmation is provided by genetic testing.

Treatment

There is no prevention, and the syndrome itself cannot be cured. The prognosis is unfavorable.

The risk of malignant disease can be reduced through regular medical surveillance, including frequent examinations and imaging methods, particularly regular colonoscopies, allowing for early detection of cancer. In some cases, prophylactic surgical procedures are performed, including removal of the colon filled with polyps or other preventive surgeries (removal of organs before malignant transformation occurs).

However, it is impossible to fully control all the cells in the body, as the APC gene mutation is present in all cells, making the organism highly predisposed to tumor development (metaphorically, “a large powder keg”). Eventually, a malignant tumor is likely to develop.

Patients with Gardner syndrome rarely survive beyond 50 years of age. If the polyp‑filled colon is not removed in time, malignant transformation typically occurs around the age of 39.

• a large number (hundreds to thousands) of intestinal polyps in the colon – lesions arising from the mucosa, typically appearing on average around the age of 16. In Gardner syndrome, these are benign tumors that unfortunately have a tendency to undergo malignant transformation, i.e., they may progress to colorectal cancer
• increased occurrence of malignant tumors of the thyroid gland, liver, brain, kidneys, adrenal glands, and gallbladder
• relatively frequent development of multiple benign bone tumors (osteomas) and benign subcutaneous connective tissue tumors (fibromas)
• dental abnormalities
• adenomatous changes in the stomach and small intestine
• congenital hypertrophy of the retinal pigment epithelium (CHRPE)
• benign skin lesions such as epidermoid cysts, fibromas, and lipomas