Authorship list:
Author Contributions:
Kie Yamashiro , Katsuhisa Sekido, Yasushi Hariya contributed to the manuscript preparation. Michiko Okita, Masashi Harada, Yasushi Hariya, and Masaharu Tatetsu contributed to the patient management. All authors read and approved the final manuscript.
Acknowledgments: The authors would like to thank Dr. Eiji Nakayama, Professor at Health Sciences University of Hokkaido, for assistance with diagnostic imaging, and Dr. Tomoyuki Oouchi, Chief of the Department of Pathology at Keiyukai Sapporo Hospital, for assistance with the pathological investigation.