Masses of the skin may be better termed nodules if they are larger than 0.5 cm and are not just neoplastic in origin. The term VINDICATEserves as a useful mnemonic to recall the important skin masses. When the physician is considering the cause of a mass in any part of the body, he or she must include a possible skin mass in the differential. Therefore, although I have limited the discussion of skin lesions in other sections, the reader should turn to this section if the mass is thought to originate in the skin.
· V—Vascular lesions include cavernous hemangiomas, varicose veins, hemorrhages from scurvy or coagulation disorders, and emboli from subacute bacterial endocarditis (SBE) (Osler nodules).
· I—Inflammatory masses include caruncles, furuncles, warts, condyloma latum and acuminatum, molluscum contagiosum, tuberculomas, gummas, and granulomas from coccidioidomycosis, sporotrichosis, and other fungi.
· N—Neoplasms constitute the largest group of skin masses. The important ones to remember are basal and squamous cell carcinomas, melanomas, nevi, sarcomas, metastatic nodules, Kaposi sarcomas, lipomas, neurofibromatosis, dermoid cysts, leiomyomas, lymphangiomas, and mycosis fungoides. Leukemic infiltration and Hodgkin disease may cause skin nodules or plaques.
· D—Degenerative diseases do not produce any skin masses worthy of mention but do predispose to pressure sores. Heberden nodes of osteoarthritis should be considered here.
· I—Intoxication suggests the lesions of bromism.
· C—Cystic lesions of the skin include sebaceous cysts, epithelial cysts, and dermoid cysts. Congenital lesions such as eosinophilic granulomas of the skin, tuberous sclerosis, and neurofibromatosis should not be overlooked.
· A—Autoimmune disease includes the aneurysms of periarteritis nodosa, rheumatoid and rheumatic nodules, localized lupus or amyloidosis, and Weber–Christian disease.
· T—Trauma induces contusions and edema of the skin.
· E—Endocrine and metabolic diseases that cause skin masses are diabetes mellitus (abscesses, necrobiosis lipoidica diabeticorum), hyperthyroidism (pretibial myxedema, acromegaly [tufting of the distal phalanges]), gout (tophaceous deposits), hyperlipemia and hypercholesterolemia with multiple xanthomas, and calcinosis in hypercalcemic states.
Approach to the Diagnosis
A biopsy or excision is the best approach to the diagnosis. If a systemic disease is suspected because of a lesion, appropriate studies for these are listed below.
Other Useful Tests
1. CBC (abscess)
2. Sedimentation rate (infection)
3. Incision and drainage (I & D) and culture of exudate
4. Tuberculin test
5. Skin tests and serology for fungi
6. Kveim test (sarcoidosis)
7. ANA analysis (collagen diseases)
8. Frei test (lymphogranuloma venereum)
9. Muscle biopsy (collagen disease)