Association between palisaded and interstitial granulomatous dermatoses and haematological neoplasms: evidence beyond coincidence?

Abstract Background Palisaded and interstitial granulomatous dermatoses are a spectrum of presumed reactive cutaneous disorders sometimes associated with underlying diseases, notably malignant haemopathies. Specific associations between some of these dermatoses and particular haematological neoplasms may exist. Objectives To describe the spectrum of haematologic neoplasms associated with palisaded and interstitial granulomatous dermatoses and to establish whether specific associations exist. Methods We conducted a retrospective monocentric study of all cases of palisaded and interstitial granulomatous dermatoses associated with haematologic neoplasms seen in our department, completed with a systematic literature review. Clinical and pathological data were extracted from patient files and articles. Results A hundred and forty-six cases were identified (31 from our institution, 115 from the literature review). Granuloma annulare (n=76) and elastolytic giant cell granulomas (n=9) were mainly associated with B- and T-cell lymphoid neoplasms (69.4% of cases). Four cases of necrobiosis lipoidica were identified, of which 2 were associated with plasma cell dyscrasias. Interstitial granulomatous dermatitis (n=22) were associated in half of cases with myeloid neoplasms. This association was even stronger (64.7%) for palisaded neutrophilic granulomatous dermatitis (n=17), especially with chronic myelomonocytic leukaemia (47.1%). We also identified 18 cases of unclassified granulomatous dermatoses which were most often associated with lymphoid neoplasm (55.6%). Anamnestic arguments suggestive of a non-coincidental link were identified in 40 cases in total (27.4%). Conclusion This work shows that there is a preferential link between some palisaded or interstitial granulomatous dermatoses and types of haematological neoplasms, the pathophysiological nature of which remains to be elucidated.