From the Guidelines
Shave biopsies are not recommended for diagnosing suspected melanoma due to their inability to accurately determine the depth of invasion, which is crucial for melanoma staging and treatment planning. The most recent and highest quality study, published in 2019 in the Journal of the American Academy of Dermatology 1, recommends excisional biopsies as the ideal method for diagnosing primary cutaneous melanoma, as they allow for the removal of the entire lesion with a small margin of normal skin, providing accurate staging information. While shave biopsies may be appropriate for other skin lesions, they are suboptimal for melanoma diagnosis, and their use may lead to incorrect diagnosis or staging, potentially complicating treatment decisions.
Some studies, such as the one published in 2012 in the Journal of the National Comprehensive Cancer Network 1, suggest that patients diagnosed with melanoma through shave biopsy may not need to be managed differently than those diagnosed with excisional biopsy. However, this study is not as recent or of the same quality as the 2019 study, and its findings should be considered with caution.
The key points to consider when diagnosing suspected melanoma are:
- Excisional biopsies are the preferred method for diagnosing primary cutaneous melanoma
- Shave biopsies are suboptimal for melanoma diagnosis due to their inability to accurately determine the depth of invasion
- Incisional biopsies may be acceptable in certain circumstances, but excisional biopsies are generally preferred
- The goal of biopsy is to provide accurate staging information, which is crucial for treatment planning.
In summary, excisional biopsies are the recommended method for diagnosing suspected melanoma, as they provide the most accurate staging information, which is essential for treatment planning, and ultimately, for improving patient outcomes in terms of morbidity, mortality, and quality of life.
From the Research
Diagnosis of Melanoma using Shave Biopsy
- Shave biopsy can be used to diagnose melanoma, with studies showing its accuracy and reliability in the overwhelming majority of cases 2.
- A study published in the Journal of the American College of Surgeons found that shave biopsy was accurate in 97% of cases, with only 3% of patients experiencing T-stage upstaging 2.
- Another study published in The Journal of surgical research found that shave biopsy was the most frequent method of diagnosis of cutaneous melanoma, and that while it may underestimate true T-stage, it did not affect the need for reoperation due to T-upstaging 3.
Accuracy of Shave Biopsy in Predicting Breslow Depth
- A study published in The American surgeon found that shave biopsy underestimated the final Breslow depth of melanoma in 13% of patients, but changed the management of few patients 4.
- Another study published in the American journal of surgery found that shave biopsy results showed significantly more positive deep margins, and a higher risk of finding residual tumor in the wide local excision 5.
- A study published in the Journal of the American Academy of Dermatology found that deep shave biopsy was preferable to superficial shave or punch biopsy for thin and intermediate depth melanomas 6.
Comparison with Other Biopsy Methods
- A study published in the American journal of surgery found that excisional biopsy was the most accurate method of biopsy, with punch and shave biopsies demonstrating a significant risk of finding residual tumor in the wide local excision 5.
- Another study published in the Journal of the American Academy of Dermatology found that excisional biopsy was the most accurate method of biopsy, with deep shave biopsy being preferable to superficial shave or punch biopsy for thin and intermediate depth melanomas 6.