SECTION 19: SKIN SIGNS OF SYSTEMIC CANCERS

MUCOCUTANEOUS SIGNS OF SYSTEMIC CANCERS ICD-10: M8000/6

• Mucocutaneous findings may suggest systemic cancers in several ways:

  • Associations of heritable mucocutaneous disorders with systemic cancers.

  • By action at a distance, i.e., paraneoplastic syndromes.

• Or spread of cancer to the skin or mucosal sites by direct, lymphatic, or hematogenous extension (cutaneous metastasis).

CLASSIFICATION OF SKIN SIGNS OF SYSTEMIC CANCER

METASTATIC CANCERS

PERSISTENT TUMOR Lymphatic extension and hematogenous spread¹.

DIRECT EXTENSION Paget disease and extramammary Paget disease.

Lymphomas with secondary skin involvement (Section 21).

HERITABLE DISORDERS

Cowden Syndrome

Peutz–Jeghers Syndrome

Neurofibromatosis (see Section 16).

Tuberous sclerosis (see Section 16).

Multiple endocrine neoplasia (types 1 and 2b).

PARANEOPLASTIC SYNDROMES

Acanthosis nigricans, malignant, tripe palms

• Acquired ichthyosis

• Bazex syndrome

• Carcinoid syndrome

• Dermatomyositis (see Section 14)

• Ectopic ACTH syndrome

• Erythema gyratum repens

• Gardner syndrome

Glucagonoma syndrome

• Hypertrichosis lanuginosa

• Muir–Torre syndrome

• Palmar keratoses

Paraneoplastic pemphigus (paraneoplastic autoimmune multiorgan syndrome)

• Pruritus

• Pyoderma gangrenosum (see Section 7)

• Sweet syndrome (see Section 7)

• Vasculitis (see Section 14)

METASTATIC CANCER TO THE SKIN ICD-10: M8000/6

• Metastatic cancer to the skin is characterized by solitary or multiple dermal or subcutaneous nodules, occurring as metastatic cells from a distant noncontiguous primary malignant neoplasm*.

• They are transported to and deposited in the skin or subcutaneous tissue by one of the following routes:

  • Lymphatic routes.

  • Hematogenous spread.

  • Contiguous spread across the peritoneal cavity or other tissues.

• Skin lesions nodule (Figs. 19-1 and 19-2), raised plaque, thickened fibrotic area. First detected when <5 mm. The fibrotic area may resemble morphea; occurring on scalp, may produce alopecia. Initially, epidermis is intact and stretched over nodule; in time, the surface may become ulcerated (Fig. 19-3) or hyperkeratotic. It may appear inflammatory, i.e., pink to red or hemorrhagic. Firm to indurated. May be solitary, few, or multiple. May acquire considerable size and may be mistaken for a primary skin cancer (Fig. 19-3).