Department of Skin Oncology/Dermatology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan

Sadao Inoue, Shigeru Koizumi, Takaya Komori & Yasuhiro Nakamura

Department of Dermatology, Dokkyo Medical University, Mibu, Tochigi, Japan

Sadao Inoue & Ken Igawa

Department of Dermatology, Chiba University, Chiba, Japan

Shigeru Koizumi, Yosuke Yamamoto & Takashi Inozume

Department of Dermatologic Oncology, National Cancer Center Hospital, Tokyo, Japan

Naoya Yamazaki, Eiji Nakano & Dai Ogata

Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan

Yuki Ichigozaki & Satoshi Fukushima

Department of Dermatology, Mie University, Tsu, Japan

Hiroshi Kitagawa

Department of Dermatology, Shinshu University, Matsumoto, Japan

Yukiko Kiniwa

Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo, Japan

Sayuri Sato & Hisashi Uhara

Department of Dermatology, Hyogo Cancer Center, Akashi, Japan

Toshihiro Takai

Department of Dermatology, Kurume University School of Medicine, Kurume, Japan

Reiichi Doi & Kenta Nakama

Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan

Takamichi Ito

Department of Dermatology, Gunma University, Maebashi, Gunma, Japan

Masahito Yasuda

Department of Dermatology and Allergology, Nagasaki University Hospital, Nagasaki, Japan

Yutaka Kuwatsuka

Department of Dermatology, Jichi Medical University, Shimotsuke, Tochigi, Japan

Takeo Maekawa

Department of Dermatology, Saitama Medical Center, Jichi Medical University, Saitama, Japan

Takeo Maekawa

Department of Dermatology, Kyoto Prefectural University of Medicine, Kyoto, Japan

Jun Asai

Department of Dermatology, University of Tokyo, Tokyo, Japan

Takuya Miyagawa

Department of Dermato-Oncology, NHO Kagoshima Medical Center, Kagoshima, Japan

Shigeto Matsushita

Department of Dermatology, Keio University School of Medicine, Tokyo, Japan

Takeru Funakoshi

Department of Dermatology, Toranomon Hospital, Tokyo, Japan

Akiko Kishi

Department of Dermatology, Niigata Cancer Center Hospital, Niigata, Japan

Tatsuya Takenouchi

Department of Dermatology, Shiga University of Medical Science, Otsu, Japan

Hiraku Kokubu

Department of Dermatology, Hitachi General Hospital, Hitachi, Ibaraki, Japan

Shusaku Ito

Department of Dermatology, Kawasaki Medical School, Kurashiki, Japan

Yoshiyasu Umeda

Department of Dermatology, Wakayama Medical University, Wakayama, Japan

Yuki Yamamoto

Department of Dermatology, University of Tsukuba, Tsukuba, Japan

Shoichiro Ishizuki

Department of Dermatology, University of Fukui, Fukui, Japan

Shiro Iino

Department of Dermatology, NHO Kyushu Cancer Center, Fukuoka, Japan

Hiroshi Uchi

Department of Dermatology, Asahikawa Medical University, Asahikawa, Japan

Tomoe Nakagawa

Department of Dermatology, Kimitsu Chuo Hospital, Kisarazu, Japan

Kazuhiro Inafuku

Department of Dermatology, Kesennuma City Hospital, Kesennuma, Miyagi, Japan

Takahiro Haga

Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Japan

Takahide Kaneko

Department of Plastic and Reconstructive Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan

Masahiro Nakagawa

Department of Dermatology, Central Japan International Medical Center, Gifu, Japan

Hideki Kamiya

Department of Dermatology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan

Masaru Arima

Department of Dermatology, Nippon Medical School Hospital, Tokyo, Japan

Toshihiko Hoashi

Department of Dermatology, Teikyo University, Tokyo, Japan

Azusa Hiura

Department of Dermatology, Hyogo Medical University, Nishinomiya, Hyogo, Japan

Nobuo Kanazawa

Department of Dermatology, Takamatsu Red Cross Hospital, Takamatsu, Japan

Keiko Manabe

Department of Dermatology, Saitama Cancer Center, Saitama, Japan

Masashi Ishikawa

Department of Dermatology, NHO Okayama Medical Center, Okayama, Japan

Kenji Asagoe

Department of Dermatology, Metropolitan Hiroo Hospital, Tokyo, Japan

Utsugi Iwasawa

Department of Dermatology, St. Marianna University, Kawasaki, Japan

Takafumi Kadono

Department of Dermatology, Toyama Prefectural Central Hospital, Toyama, Japan

Naohito Hatta

Department of Dermatology, Itami City Hospital, Itami, Japan

Shoichiro Minami

Yasuhiro Nakamura and Sadao Inoue designed the study. Sadao Inoue and Shigeru Koizumi performed the data collection. Takashi Inozume, Yosuke Yamamoto, Naoya Yamazaki, and Ken Igawa supervised the study and verified the analytical methods. All authors contributed to data interpretation and manuscript writing. All authors read and approved the final manuscript.