Multiple cutaneous malignancies in a patient with pityriasis rubra pilaris and focal acantholytic dyskeratosis

The Incidence of Acantholysis in Pityriasis Rubra Pilaris—Histopathological Study Using Multiple-Step Sections and Clinicopathologic Correlations

“…In addition, there were reports of selected or collected PRP cases with acantholysis adding up to 27 of 47 (mean: 57%) biopsies with acantholysis. 2,[5][6][7][8][9][10][11][12][13]15 Acantholysis was not present in the initial sections of any of our PRP biopsies, but in 6.5%-46% (mean: 31%) of the step sections of 5 biopsies, suggesting that acantholysis may not be a constant histopathological characteristic of PRP, and it may be present in only the minority of the sections.…”

“…Proteolytic enzymes were speculated as causative agents, 2,11 in accordance with the nonspecific pattern of acantholysis seen in our cases and in previous ones. [2][3][4][5][6][7][8][9][10][11][12][13][14][15] Understanding the mechanism of acantholysis may shed more light on the molecular basis and the pathogenesis of PRP.…”

Pityriasis rubra pilaris

“…4). 59 , 89 , 94–98 These nonspecific histologic findings had been previously recognized in other conditions, such a Darier–White disease, Grover's disease, Hailey–Hailey disease, and pemphigus, but not PRP. Magro and Crowson 89 found acantholytic dyskeratosis in 23 of 32 biopsies from patients with PRP, and in zero of 23 biopsies in a control group with psoriasis, indicating that it is an important feature for distinguishing between the two diseases.…”

“…It has rarely been reported as the initial manifestation of an internal malignancy 56–58 . PRP occurred in a patient with multiple cutaneous malignancies 59 . Prominent 20 or increasing 60 seborrheic keratoses have been reported in erythrodermic PRP, but with no apparent malignancy as defined in the sign of Leser–Trélat.…”

Pityriasis rubra pilaris: the clinical context of acantholysis and other histologic features

“…Kao and Sulica 1 first described acantholytic dyskeratosis in pityriasis rubra pilaris (PRP) in 1989. Currently 32 cases of PRP with acantholysis on biopsy can be found in the English‐language literature, 2,3 mostly in dermatopathology journals 4–7 . Although the initial finding of acantholysis in PRP was thought to be incidental, 1 subsequent case reports 5,6 and a series by Magro and Crowson 4 documented persistent findings of acantholysis in PRP.…”