Immediate Excisional Biopsy is Required
This patient requires urgent excisional biopsy of the back lump within 2 weeks, performed by a dermatologist or surgeon with expertise in pigmented lesions, given the rapid growth, new pain, and family history of melanoma. 1, 2
Why This is Urgent
- Progressive change in lesion size is a major red flag for melanoma that mandates immediate referral or excision 1
- The doubling in size over 2 months with new pain represents concerning evolution that cannot be dismissed as a benign lipoma 2
- Family history of melanoma significantly increases this patient's risk and lowers the threshold for aggressive evaluation 3
- Even if this appears clinically like a lipoma, rapidly changing soft tissue masses require tissue diagnosis to exclude malignancy 2
Critical Next Steps
1. Urgent Specialist Referral (Within 2 Weeks)
- Refer to dermatologist or surgeon experienced in pigmented/suspicious lesions 1, 2
- Do not delay for imaging or other workup first 2
2. Complete Physical Examination Before Biopsy
- Full body skin examination to detect any additional suspicious lesions or primary melanoma 1, 2
- Palpate all regional lymph nodes (axillary, cervical, supraclavicular) as regional lymph node enlargement is highly suggestive of melanoma with nodal metastasis 1
- Document exact lesion location, size, color, borders, and any associated skin changes 2
3. Proper Biopsy Technique is Critical
- Full-thickness excisional biopsy with 2-5 mm margin of normal skin and subcutaneous fat is mandatory 3, 2
- Use a surgical scalpel, never laser or electrocautery, as tissue destruction compromises diagnosis 3, 2
- The entire lesion must be removed intact for accurate histopathological assessment 3
- Shave or punch biopsies are absolutely contraindicated as they prevent accurate Breslow thickness measurement if melanoma is present 4, 2
Why the Initial "Lipoma" Assessment Was Inadequate
- Clinical appearance alone cannot reliably distinguish benign from malignant lesions 2
- Any change in a previously stable lesion warrants tissue diagnosis, regardless of initial clinical impression 1, 2
- Amelanotic melanomas and other aggressive subtypes can mimic benign lesions 5
- Deep melanomas can present as subcutaneous nodules without overlying pigmentation changes 3
Required Histopathology Information
If melanoma is confirmed, the pathology report must include 3, 2:
- Breslow thickness in millimeters (most important prognostic factor) 1
- Clark level of invasion 3
- Presence and extent of ulceration 2
- Surgical margin clearance status 2
- Mitotic rate 3
- Presence of regression 3
Post-Biopsy Management Depends on Results
If Benign (e.g., confirmed lipoma):
- No further treatment needed if completely excised 2
- Continue routine skin surveillance given family history 3
If Melanoma Confirmed:
- Staging workup with complete lymph node examination and consideration of imaging (CT chest/abdomen/pelvis, brain MRI) if Breslow thickness ≥1 mm or other high-risk features 3
- Wide local excision with margins based on Breslow thickness: 1 cm for <1 mm, 1-2 cm for 1-2 mm, 2-3 cm for >2 mm 3, 4
- Sentinel lymph node biopsy should be discussed if thickness ≥0.8-1.0 mm or if ulceration/high mitotic rate present 4, 6
- Referral to multidisciplinary melanoma team for stage IB or higher disease 3
Common Pitfall to Avoid
Do not reassure and observe based on clinical appearance alone. The combination of rapid growth, new symptoms, and family history overrides any benign-appearing clinical features 1, 2. Delayed diagnosis of melanoma significantly worsens prognosis, as survival correlates directly with Breslow thickness at diagnosis 1, 6.