Uterine leiomyoma (UL), commonly known as fibroids, are benign tumors of the uterine myometrium. They represent the most prevalent pelvic tumors in women and are found in more than 75% of women of reproductive age. Approximately 20 to 25% of women with UL exhibit symptoms including menorrhagia, infertility, pelvic pain, and a range of complications during pregnancy. UL are the leading cause for hysterectomy in the United States, accounting for 30% of all hysterectomies (summary by Eggert et al., 2012).

Uterine leiomyoma (UL), commonly known as fibroids, are benign tumors of the uterine myometrium. They represent the most prevalent pelvic tumors in women and are found in more than 75% of women of reproductive age. Approximately 20 to 25% of women with UL exhibit symptoms including menorrhagia, infertility, pelvic pain, and a range of complications during pregnancy. UL are the leading cause for hysterectomy in the United States, accounting for 30% of all hysterectomies (summary by Eggert et al., 2012).

FH tumor predisposition syndrome is characterized by cutaneous leiomyomata, uterine leiomyomata (fibroids), and/or renal tumors. Pheochromocytoma and paraganglioma have also been described in a small number of families. Cutaneous leiomyomata appear as skin-colored to light brown papules or nodules distributed over the trunk and extremities, and occasionally on the face, and appear at a mean age of 30 years, increasing in size and number with age. Uterine leiomyomata tend to be numerous and large; age at diagnosis ranges from 18 to 53 years, with most women experiencing irregular or heavy menstruation and pelvic pain. Renal tumors are usually unilateral, solitary, and aggressive. They are associated with poor survival due to clinical aggressiveness and propensity to metastasize despite small primary tumor size. The median age of detection is approximately age 40 years.

SADDAN dysplasia (severe achondroplasia with developmental delay and acanthosis nigricans) is a very rare skeletal dysplasia characterized by the constellation of these features. Radiology reveals 'ram's horn' shaped clavicles and reverse bowing of lower limbs. Approximately half of patients die before the fourth week of life secondary to respiratory failure (summary by Zankl et al., 2008).

Familial adenomatous polyposis-4 is an autosomal recessive tumor predisposition syndrome characterized by the development of multiple colonic adenomas in adulthood, often with progression to colorectal cancer. Proliferative lesions in other tissues may also occur (summary by Adam et al., 2016). For a discussion of genetic heterogeneity of familial adenomatous polyposis, see FAP1 (175100).