Which biopsy approach provides definitive diagnosis and assessment of nodal status for melanoma?

Which biopsy approach provides definitive diagnosis and assessment of nodal status for melanoma?

• A. Incisional biopsy only.
• B. Full thickness wide excisional biopsy plus lymph node biopsy.
• C. Shave biopsy only.
• D. Fine needle aspiration of lymph node only.

Answer: (B)

Obtaining an accurate diagnosis and staging for melanoma relies on two things: the depth and features of the primary tumor, and the status of regional lymph nodes. A full-thickness wide excisional biopsy removes the entire lesion with enough surrounding tissue to include the full depth of invasion. This is essential to measure Breslow depth, assess ulceration, mitotic rate, and other histologic features that determine prognosis and guide management. Other biopsy methods, like shave or partial/incisional sampling, often miss the deepest part of the tumor, which can underestimate depth and give a misleading diagnosis. For nodal status, biopsy of the draining lymph nodes is needed. This is typically done with a lymph node biopsy, ideally a sentinel lymph node biopsy, to determine whether the cancer has spread. Biopsy of the lymph node alone cannot establish the diagnosis on the skin and does not provide full staging, and superficial skin biopsies cannot reliably assess depth. Together, a full-thickness wide excisional biopsy of the lesion plus biopsy of the draining lymph node provides the definitive diagnosis and the nodal status needed for proper staging and treatment planning.

Obtaining an accurate diagnosis and staging for melanoma relies on two things: the depth and features of the primary tumor, and the status of regional lymph nodes. A full-thickness wide excisional biopsy removes the entire lesion with enough surrounding tissue to include the full depth of invasion. This is essential to measure Breslow depth, assess ulceration, mitotic rate, and other histologic features that determine prognosis and guide management. Other biopsy methods, like shave or partial/incisional sampling, often miss the deepest part of the tumor, which can underestimate depth and give a misleading diagnosis.

For nodal status, biopsy of the draining lymph nodes is needed. This is typically done with a lymph node biopsy, ideally a sentinel lymph node biopsy, to determine whether the cancer has spread. Biopsy of the lymph node alone cannot establish the diagnosis on the skin and does not provide full staging, and superficial skin biopsies cannot reliably assess depth.

Together, a full-thickness wide excisional biopsy of the lesion plus biopsy of the draining lymph node provides the definitive diagnosis and the nodal status needed for proper staging and treatment planning.