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Clinical Outcomes and Prognostic Factors for Extramammary Paget’s Disease Treated with Radiation Therapy: A Multi-Institutional Observational Study
by
, , , , , , , and
Masanari Niwa
1,*, 
Natsuo Tomita
1
,
Hiromichi Ishiyama
2,
Hijiri Kaneko
2,
Yukihiko Oshima
3,
Hirota Takano
4,
Masayuki Matsuo
4,
Mayu Kuno
5,
Akifumi Miyakawa
6,
Shinya Otsuka
7,
Taiki Takaoka
1,
Dai Okazaki
1,
Akira Torii
1,
Nozomi Kita
1,
Seiya Takano
1,
Motoki Nakamura
8,
Hiroshi Kato
8,
Akimichi Morita
8 and
Akio Hiwatashi
1 1
Department of Radiology, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan
2
Department of Radiation Oncology, Kitasato University Hospital, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0375, Japan
3
Department of Radiology, Aichi Medical University Hospital, Nagakute, Japan, 1-1 Yazako-Karimata, Nagakute 480-1195, Japan
4
Department of Radiation Oncology, Gifu University Hospital, 1-1 Yanagido, Gifu 500-1194, Japan
5
Department of Radiation Oncology, Ichinomiya Municipal Hospital, 2-2-22, Bunkyo, Ichinomiya 491-8558, Japan
6
Department of Radiation Oncology, National Hospital Organization Nagoya Medical Center, 4-1-1, Sannomaru, Nakaku, Nagoya 460-0001, Japan
7
Department of Radiology, Okazaki City Hospital, 3-1, Kouryuuji-cho Gosyoai, Okazaki 444-8553, Japan
8
Department of Geriatric and Environmental Dermatology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan
*
Author to whom correspondence should be addressed.
Cancers 2025, 17(9), 1507; https://doi.org/10.3390/cancers17091507 (registering DOI)
Submission received: 14 March 2025
/
Revised: 24 April 2025
/
Accepted: 28 April 2025
/
Published: 29 April 2025
(This article belongs to the Section Clinical Research of Cancer)
Simple Summary
Extramammary Paget’s disease (EMPD) is a rare skin cancer that usually affects older adults and appears in the genital and perianal regions. This study analyzed the outcomes of radiation therapy in 81 patients with EMPD. The three-year local control, progression-free survival, and overall survival rates were 75%, 52%, and 80%, respectively. The results showed that lymph node metastasis, not having surgery, and using local radiation only without treating nearby lymph nodes were linked to worse outcomes. Side effects were generally mild, with only one patient experiencing moderate skin infection and another having severe lymphedema, while no very severe side effects occurred. These findings suggest that surgery and treating nearby lymph nodes in addition to radiation may improve outcomes for EMPD patients. Further research is needed to determine the best treatment approach, especially for older patients with poor prognostic factors.
Abstract
Background: Extramammary Paget’s disease (EMPD) is a rare cutaneous carcinoma that typically affects the elderly and is frequently observed in genital and perianal regions. We analyzed the outcomes and prognostic factors for EMPD after radiation therapy (RT). Methods: We analyzed data from 81 patients with non-metastatic EMPD who received either RT alone or in combination with surgery and/or chemotherapy. The median radiation dose was 56 Gy in 28 fractions. Local control (LC), progression-free survival (PFS), and overall survival (OS) rates were calculated using the Kaplan–Meier method. Multivariate analyses were performed using the Cox proportional hazards model. Late adverse events were evaluated by NCI-CTCAE version 5.0. Results: The median age was 78 years, and the median follow-up period was 36 months. The three-year LC, PFS, and OS rates were 75%, 52%, and 80%, respectively. Multivariate analyses identified the presence of lymph node (LN) metastasis, the absence of surgery, and the omission of elective nodal irradiation (i.e., local irradiation only) as significant factors for unfavorable LC (p = 0.01, 0.02, and 0.006) and PFS (p = 0.001, 0.04, and 0.03). LN metastasis was also a significant factor for unfavorable OS (p = 0.005). One patient developed grade 2 skin infection, and another developed grade 3 lymphedema; no grade 4 or higher toxicity was observed. Conclusion: The present results revealed prognostic factors for EMPD after RT and suggest that the absence of surgery and omission of elective nodal irradiation worsened outcomes. A prospective study is needed to establish an optimal treatment strategy for this rare malignancy, which is common in the elderly.
