Comment on skin biopsies for diagnosing intravascular lymphoma: A retrospective study of diagnostic accuracy

Recommendations for an Approach to Random Skin Biopsy in the Diagnosis of Intravascular B-Cell Lymphoma

“…Consideration of biopsy delay should occur if the patient was treated with oral or intravenous steroids in the previous three 3 to five 24 days as it increases the risk of false negatives. 3,24 IVBCL lesions in RSB are most consistently present in small vessels in the subcutaneous fat [12][13][14] . RSB does carry an inherent risk of bleeding, especially in this patient population where thrombocytopenia is common and in one case report 25 incisional biopsy (6 in total completed) may have contributed to hemorrhagic shock and death of a patient due to blood loss.…”

“…14 In 114 incisional RSB specimens from 111 patients in Matsue et al, 3 the sensitivity, specificity and positive and negative predictive values were 77.8%, 98.7%, 96.6% and 90.6%, respectively. Some authors have questioned the diagnostic utility of using a superficial 4 mm punch biopsy for RSB to consistently diagnose IVBCL 10,[12][13][14] citing that these 4 mm punch biopsies sample the superficial 4-5mm of skin and do not sample a deep enough section of subcutaneous fat 10 where the diagnosis of IVBCL via RSB is more consistently made. 13,14 Some authors have championed incisional biopsy down to the fascial plane noting 37% of IVBCL lesions were present only if the subcutaneous tissue had a minimum depth of 5 mm from the skin surface to the lesion.…”

“…23 This publication was a Clinical Image with no accompanying data on sensitivity and specificity, however did manage to achieve 12.8 mm depth of biopsy, likely conferring similar diagnostic yield to incisional biopsy as biopsy depth is comparable. 13,14 Others have noted telescoping punch biopsies may increase the risk of unintended prolonged post-procedure bleeding. 13 Site selection of RSB is also an important consideration.…”

“…13,14 Others have noted telescoping punch biopsies may increase the risk of unintended prolonged post-procedure bleeding. 13 Site selection of RSB is also an important consideration. Owing to the depth of the biopsy needed for consistent diagnosis of IVBCL, the thigh, abdomen, and posterior upper arm are suitable sites for biopsy 3,14,22,23,25 with some studies opting to perform RSB on all three sites.…”

“…8 When the diagnosis is suspected, various areas may be targeted for a biopsy including the brain, lung, bone marrow and skin, with or without signs of cutaneous disease. 2,4,5,9,10 Over the last 20 years, there have been studies 3,[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] noting the utility of random skin biopsy (RSB) in the diagnosis of IVBCL with many of these touting the relatively minimally invasive nature of RSB. As a result of the sensitivity (77.8%), specificity (98.7%) and positive and negative predictive values (96.6% and 90.6%, respectively) put forth by Matsue et al 3 and the ease of cutaneous biopsy, dermatologists have become part of the care team responsible for the diagnosis of IVBCL.…”