Cutaneous leiomyoma

Piloleiomyoma · angioleiomyoma · genital leiomyoma · cutaneous leiomyomata

Cutaneous leiomyomas are benign smooth-muscle tumours arising from arrector pili muscle (piloleiomyoma — most common), vascular smooth muscle (angioleiomyoma), or genital smooth muscle (dartoic). Multiple piloleiomyomata are a hallmark of hereditary leiomyomatosis and renal cell cancer (HLRCC / Reed syndrome) — an autosomal-dominant FH (fumarate hydratase) gene cancer-predisposition syndrome. Recognition prompts referral for genetic testing and renal surveillance.

CurrentLast reviewed 16 May 2026

Subtypes

Piloleiomyoma: from arrector pili; commonest cutaneous leiomyoma; multiple in HLRCC.
Angioleiomyoma (vascular leiomyoma): from vascular smooth muscle; typically solitary; lower limb of women.
Genital leiomyoma (vulval / scrotal / nipple): from smooth muscle of vulva, scrotum, nipple.

Pathology

Dermal / subcutaneous nodule of intersecting bundles of smooth-muscle cells.
Eosinophilic spindle cells with cigar-shaped nuclei, low N:C ratio, bland nuclei.
No atypia, no mitoses, no necrosis.
IHC: smooth muscle actin+, desmin+, h-caldesmon+; S100 negative.
HLRCC-associated piloleiomyoma: fumarate hydratase (FH) immunostain loss; 2-succinated cysteine (2SC) positive staining.

Clinical features

Piloleiomyoma:
- Multiple firm pink-brown / red-brown papules and nodules, 0.5-2 cm.
- Clustered or zosteriform distribution.
- Sites: trunk (especially shoulder, chest, back), extensor limbs.
- Painful — particularly with cold, pressure, emotional stress.
- Onset adolescence-early adulthood; progressive.
Angioleiomyoma:
- Solitary; lower limb common; women.
- 2-15 mm; painful on palpation.
- Slow growth.
Genital leiomyoma:
- Solitary; vulva (commonest), scrotum, nipple, mammary line.
- Asymptomatic or mildly painful.

HLRCC / Reed syndrome

Autosomal-dominant cancer predisposition; FH (fumarate hydratase) gene on chromosome 1q42.
Triad:
1. Multiple cutaneous piloleiomyomas.
2. Uterine fibroids (early-onset, multiple, aggressive).
3. Renal cell carcinoma — type 2 papillary, aggressive, early-onset.
RCC lifetime risk ~10-30%; often presents stage III/IV; metastasises early.
Referral for:
- Clinical genetics + germline FH testing.
- Annual renal MRI from age 8-10 years.
- Annual gynaecology review (fibroid burden).

Management

Cutaneous leiomyomas:
- Symptomatic management:
  - NSAIDs.
  - Calcium-channel blockers (nifedipine 10-30 mg TDS); α-adrenergic blockers (doxazosin); GABA-analogues (gabapentin / pregabalin).
  - Topical capsaicin.
- Excision of symptomatic lesions; new lesions may develop.
- Cryotherapy / electrosurgery — limited evidence.
HLRCC-confirmed:
- Clinical genetics + cascade family testing.
- Annual contrast-enhanced renal MRI from age 8-10.
- Counsel about RCC risk; urgent referral for any renal symptom.
- Gynaecological surveillance; early treatment of fibroids.
- Avoid tobacco / obesity (RCC risk factors).
Long-term multidisciplinary follow-up: dermatology, genetics, gynaecology, urology.

References

Reed WB et al. Multiple cutaneous and uterine leiomyomatosis associated with renal cell carcinoma. Arch Dermatol. 1973;108:683-686.

Tomlinson IP et al. Germline mutations in FH predispose to dominantly inherited uterine fibroids, skin leiomyomata and papillary renal cell cancer. Nat Genet. 2002;30:406-410.

Smit DL et al. Hereditary leiomyomatosis and renal cell cancer in families referred for fumarate hydratase germline mutation analysis. Clin Genet. 2011;79:49-59.

Schultz KAP et al. PTEN, DICER1, FH, and their associated tumor susceptibility syndromes: clinical features and surveillance recommendations. Clin Cancer Res. 2017;23:e76-e82.