Cutaneous Metastases

Synonyms

Skin metastases.

Epidemiology

Prevalence is around 2 %, incidence varying from 8 - 10% . In up to 10% of visceral tumors skin manifestation is the first sign, most commonly in breast, colon and lung carcinomas as well as in leukemias.

Definition

Cutaneous spread of malignant tumours of internal organs or hematological system, direct penetrating or via blood vessels, perineural sheet or lymphatics.

Aetiology & Pathogenesis

There is no clear pathological mechanism behind why metastases spread to the skin except by direct penetrating. Some homing factors can play a role in leukemia dissemination. Sometimes skin metastases hone into herpes zoster scars.

Signs & Symptoms

Solitary or multiple, aggregated, zosteriform or disseminated firm blue-red to yellow papules and nodules in various levels of the skin with rapid growth with a short history. Sometimes erysipelas or lymphangiosis-like pattern (cancer en cuirasse ) in breast cancer.

Localisation

If the skin metastasis is contiguous with the underlying primary, the precise type of cancer may be deduced, however this is usually not the case.

Special localisations of metastasis

Breast cancer metastases are often thoracic
Prostate: suprapubic
Sister Mary Joseph nodules located at the umbilicus derive from the ovarian and gastro-intestinal origin

Oesophageal, gastric and colonic cancers, biliary tract, pulmonary and renal carcinomas prefer hairy scalp, neck and face.

Classification

No clear classification of cutaneous metastases.

Laboratory & other workups

Histological, immunohistochemical or molecular in conjunction with tumor screening.

Dermatopathology

Immunohistochemical profiling of tumor cells.

Course

Often metastases appear in tumor-free interval. Survival after detection of metastases in most cases less than 1 year.

Complications

Depending on the type of primary tumor, stage and pretreatment. Some metastases melt away, become necrotic, bleed or become superinfected.

Diagnosis

Metastasis has to be considered in case of a rapidly growing non-classifiable lesion in the skin.

Differential diagnosis

Primary skin tumours and primary skin lymphomas, granulomatous inflitrates.

Prevention & Therapy

There is no prevention. Histological evaluation is a first step to decision algorithms for therapy of the primary tumor.

Special

Interdisciplinary approach and tumor boards to be involved.

3.3.10 Cutaneous Metastases