Excisional biopsy most accurately diagnoses cutaneous melanoma

January 01, 0001

Excisional biopsy most accurately diagnoses cutaneous melanoma

The aim of this study, a prospective case series, by researchers from Australia was to compare partial and excisional biopsy techniques in the accuracy of histopathologic diagnosis and microstaging of cutaneous melanoma. Consecutive cases from 1995 to 2006 were analysed from a tertiary referral, ambulatory care practice.

Increased odds of histopathologic misdiagnosis were associated with punch biopsy (OR, 16.6) and shave biopsy (OR, 2.6) compared with excisional biopsy. Punch biopsy was associated with increased odds of misdiagnosis with an adverse outcome (OR, 20). Other factors associated with increased odds of misdiagnosis included acral lentiginous melanoma (OR, 5.1), desmoplastic melanoma (OR, 3.8), and nevoid melanoma (OR, 28.4). Punch biopsy (OR, 5.1) and shave biopsy (OR, 2.3) had increased odds of microstaging inaccuracy over excisional biopsy. Tumor thickness was the most important determinant of microstaging inaccuracy when partial biopsy was used (odds of significant microstaging inaccuracy increased 1.8-fold for every 1 mm increase in tumor thickness). All results were significant.

The researchers concluded: "Among melanoma seen at a tertiary referral center, histopathologic misdiagnosis is more common for melanomas that have been assessed with punch and shave biopsy than with excisional biopsy. Regardless of biopsy method, adverse outcomes due to misdiagnosis may occur. However, such adverse events are more commonly associated with punch biopsy than with shave and excisional biopsy. The use of punch and shave biopsy also leads to increased microstaging inaccuracy."

Excisional biopsy appears to be the way to go for melanoma.

For the full abstract, click here.

Arch Dermatol  146(3):234-239, March 2010
© 2010 American Medical Association
The Impact of Partial Biopsy on Histopathologic Diagnosis of Cutaneous Melanoma. Jonathan C. Ng, Sarah Swain, John P. Dowling et al.

Category: S. Skin. Keywords: partial, biopsy, impact, histopathological, diagnosis, cutaneous, melanoma, prospective case series, journal watch.
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 9 April 2010

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