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Case Reports
. 2025 Aug 20;17(1):483-487.
doi: 10.1159/000547242. eCollection 2025 Jan-Dec.

Grenz Ray Therapy for Porokeratosis Ptychotropica: A Case Report

Conor Larney  1 , Dale Jobson  1   2 , Belinda Welsh  3 , Andrew Ryan  4 , Michael Webster  3
Affiliations
Case Reports

Grenz Ray Therapy for Porokeratosis Ptychotropica: A Case Report

Conor Larney et al. Case Rep Dermatol. .

Abstract

Introduction: Porokeratosis ptychotropica (PP) is a rare form of porokeratosis that poses significant diagnostic and therapeutic challenges. Given the rarity of PP, there is a paucity of evidence about effective treatment options. We present the first case of PP being managed with Grenz therapy (a type of superficial, low radiation radiotherapy).

Case presentation: Our patient was a 56-year-old female with PP in the intergluteal cleft and on her right posterior thigh. She was previously unsuccessfully treated with topical, intralesional and oral corticosteroids, topical vitamin D analogues, topical simvastatin-cholesterol cream, topical fluorouracil cream, acitretin, and CO2 laser assisted photodynamic therapy. She underwent Grenz therapy for 6 sessions, a total dose of 18 Gy to all affected areas, with excellent clinical response. After 2 months of remission, her porokeratosis showed early signs of recurrence.

Conclusion: This is the first reported case of PP being treated with Grenz rays. With no effective treatment, Grenz therapy may present a potential effective treatment for some patients.

Keywords: Case report; Grenz ray therapy; Porokeratosis ptychotropica; Superficial radiation; Treatment.

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Conflict of interest statement

All authors have no conflicts of interest to declare.

Figures

Fig. 1.
Fig. 1.
Clinical photography showing PP prior to treatment (left panels) and 2 weeks after treatment (right panels).
Fig. 2.
Fig. 2.
Skin biopsy showing follicular cornoid lamellae. H&E stain, ×10 magnification.
See this image and copyright information in PMC

References

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