I have a bump on the dorsal (back) of my hand; how should it be evaluated and managed?

Evaluation and Management of a Bump on the Dorsal Hand

A bump on the back of the hand requires clinical examination to determine if it is a benign soft tissue lesion (most common), a malignant skin tumor, or an inflammatory process, with MRI being the imaging modality of choice when the diagnosis remains unclear after initial assessment.

Initial Clinical Assessment

The evaluation should focus on specific characteristics that distinguish benign from concerning lesions:

• Examine for features suggesting malignancy: asymmetry, irregular borders, color heterogeneity, diameter >6 mm, and recent evolution in size, color, or elevation (ABCDE criteria) 1
• Assess the lesion's consistency and mobility: soft tissue masses that are fixed, firm, or rapidly growing warrant heightened concern 2
• Document baseline characteristics: record the appearance, size, and exact location of the lesion, ideally with photographs if patient consent is obtained 3
• Palpate regional lymph nodes: examine epitrochlear and axillary nodes for any enlargement that might suggest metastatic disease 1

Diagnostic Approach Based on Clinical Findings

For Suspected Benign Lesions (Ganglion Cysts, Lipomas, etc.)

Most focal hand lesions are benign, but confirmation is essential 2:

• MRI is the imaging modality of choice for evaluating soft tissue masses on the hand, as it accurately determines the nature, enhancement pattern, and exact anatomical location in relation to surrounding structures 2
• MRI features can help classify lesions as "benign," "intermediate grade" (histologically benign but locally aggressive), or "malignant" based on margin characteristics, enhancement patterns, and bony involvement 2

For Suspected Malignant Skin Lesions

If the bump has concerning features (irregular borders, ulceration, rapid growth, or atypical appearance):

• Perform full-thickness excisional biopsy with a 2 mm margin of normal skin around the lesion for definitive diagnosis 1
• The biopsy should be processed by an experienced pathology institute and include assessment of maximum thickness (Breslow), level of invasion (Clark), surgical margin clearance, and presence of ulceration 1
• Never use destructive techniques (laser, electrocautery) for initial diagnosis, as tissue destruction compromises histological evaluation 1

For Inflammatory or Infectious Processes

If the lesion appears inflamed, erythematous, or has signs of infection:

• Apply topical mupirocin 2% ointment for suspected bacterial infection, as it is highly effective against Staphylococcus aureus and beta-hemolytic streptococci 3
• Consider neutrophilic dermatosis if bilateral symmetrical hand lesions are present, as approximately 78% of neutrophilic dermatosis of the dorsal hands cases show bilateral involvement 4
• Instruct the patient to keep the area clean and dry between applications 3

Management of Confirmed Malignancies

For squamous cell carcinoma or melanoma of the dorsal hand:

• Wide excision is mandatory: use 1 cm margins for tumors with Breslow thickness of 1-2 mm, and 2-3 cm margins for thicker tumors 1
• Tissue-sparing excision has replaced amputation as the preferred approach in recent years, emphasizing preservation of function and cosmesis while achieving curative intent 5
• The dorsal hand skin can be more resistant to topical treatments than head and neck skin, warranting extended treatment periods for precancerous lesions 1

Critical Red Flags Requiring Urgent Evaluation

Instruct patients to seek immediate medical attention if:

• The lesion becomes increasingly painful, red, or swollen 3
• Fever or systemic symptoms develop 3
• The lesion bleeds spontaneously, grows significantly, or becomes protuberant 1
• Any new nodules or satellite lesions appear around the original bump 1

Common Pitfalls to Avoid

• Do not perform partial biopsies of suspicious pigmented lesions, as this risks misdiagnosis and inadequate assessment of prognostic factors 1
• Do not assume all hand bumps are benign ganglion cysts without proper evaluation, as malignant tumors can present with varied and complex clinical appearances 5
• Do not delay biopsy of lesions with atypical clinical appearance or those that fail to respond to appropriate therapy 1