Sentinel lymph-node biopsy after previous wide local excision for melanoma.

Area of Science:

• Oncology
• Surgical Pathology

Background:

• Sentinel lymph-node biopsy is often contraindicated after wide local excision for melanoma.
• This study evaluates the efficacy of sentinel lymph-node biopsy in patients with prior wide local excision.

Purpose of the Study:

• To assess the accuracy and false-negative rates of sentinel lymph-node biopsy in melanoma patients who have previously undergone wide local excision.
• To determine if prior wide local excision impacts the effectiveness of sentinel lymph-node biopsy.

Main Methods:

• Prospective cohort study of 100 patients with cutaneous melanoma (depth >1 mm or Clark level IV) after wide local excision.
• Sentinel lymph-node biopsy performed with preoperative lymphoscintigraphy for truncal lesions.
• Technetium-99m sulfur colloid injected around the scar; sentinel lymph node excised using a gamma detector.

Main Results:

• 31 out of 100 patients had sentinel lymph nodes positive for melanoma metastasis.
• The overall false-negative rate was 9% (3 patients), with two cases occurring after rotation flap closures.
• Two false-negative results were identified before the implementation of serial sectioning and immunohistochemical staining.

Conclusions:

• Sentinel lymph-node biopsy is a viable method for identifying occult nodal metastases in melanoma patients with a history of wide local excision.
• The false-negative rate, particularly in patients with rotation flap closures, warrants careful consideration.
• Improved histological examination techniques may further enhance the accuracy of sentinel lymph-node biopsy in this patient group.