Oncology

What we do

The Department of Medical Oncology delivers high-level, evidence-based systemic cancer therapies utilizing state-of-the-art global oncology knowledge.

Working seamlessly across surgical and medical specialties, we design and execute personalized treatment plans based on cancer type, stage, and individual patient health. Whether providing chemotherapy, targeted therapy, immunotherapy, or coordinating surgeries and radiation therapy, our oncologists maintain a holistic overview of each patient’s entire cancer care journey.

Key Strengths & Departmental Highlights

Multidisciplinary / Multimodality Cancer Care: Seamless coordination between Surgical Oncology, Radiation Oncology, and Medical Oncology to deliver the most effective treatment sequence.

Comprehensive Inpatient & Outpatient Integration: Close coordination with Kameda Medical Center in Kamogawa for specialized inpatient admissions, complex infusions, and supportive care.

English Consultations Available: Director Dr. Masaru Oyama provides full medical consultations in English for international patients and expatriates.

Advanced & Refractory Care: Welcoming new diagnoses, second opinions, disease recurrences, and complex or rare malignancies.

Accredited Training Center:

Certified Training Facility by the Japanese Society of Medical Oncology (JSMO)
Certified Training Facility by the Japanese Board of Cancer Therapy

Conditions we handle

We provide comprehensive systemic evaluation, chemotherapy, targeted therapy, and medical management for a wide spectrum of adult malignancies:

Thoracic & Respiratory: Lung Cancer (NSCLC/SCLC), Thymoma/Thymic Carcinoma, Thoracic Sarcoma, Malignant Pleural Mesothelioma.

Gastrointestinal (GI): Esophageal, Gastric (Stomach), Small Intestine, Colorectal, Pancreatic, Gallbladder/Biliary Tract, and Liver Cancers.

Breast & Gynecologic: Breast Cancer, Primary Breast Sarcoma, Ovarian, Uterine/Cervical, Primary Peritoneal Cancers, and Gynecologic Sarcomas.

Sarcomas & Soft Tissue Malignancies: Leiomyosarcoma, Malignant Fibrous Histiocytoma (MFH), Liposarcoma, Angiosarcoma, Rhabdomyosarcoma, Osteosarcoma, Ewing Sarcoma, and Cardiac Tumors.

Urologic & Head/Neck: Kidney (Renal Cell), Bladder, Testicular, Prostate Cancers, Pharyngeal, Laryngeal, and Tongue Cancers.

Brain & Neuro-Oncology: Glioblastoma, Oligodendroglioma, Astrocytoma, and Metastatic Brain Tumors.

Skin, Rare & Special Malignancies: Skin Cancers, Malignant Melanoma, Neuroendocrine Tumors (NET/NEC), and Cancer of Unknown Primary (CUP).

Number of cases

Total Outpatient Consultations: 11,394 patients
Total Inpatient Admissions/Care: 22,719 patient days (or admissions)

(FY2024 Track Record)

Operation results

none

List of Doctors

Chief of Oncology

Yu OYAMA

Subspeciality
Hematology， Oncology， Bone Marrow Transplantation， Autoimmune associated diseases.

Department name	Oncology
Medical School	Nihon University School of Medicine
Special Qualifications	Board Certified Physician of Japanease Society of Internal Medicine Baord Certified Specialist of American Internal Medicine Board Certified Specialist of American Oncology Board Certified Specialist of American Hematology Board Advanced Certified Specialist of Japanese Society of Medical Oncology Baord Tentative instructor of Japan Board of Cancer Therapy
Education & Career	1991.Mar. Graduated from Nihon University School of Medicine 1991.Apr. Residency in Internal Medicine， St，Luke’ｓ International Hospital 1994.May. Clinical Fellow in Hematology/Pulmonary and Critical Care Medicine，Nihon University Hospitalｓ 1996.Jun. Residency in Internal Medicine， Thomas Jefferson University Hospital 1999.Jul. Clinical Fellow in Hematology/Oncology/Stem Cell Transplantation， Northwestern University Medical School 2002.Jul. Clinical Director，Division of Immunotherapy， Assistant Professor，Department of Medicine， Northwestern University Attending Physician，Department of Medicine，Northwestern Memorial Hospital 2006.Oct. Chief ofl Oncology， Kameda Medical Center

Chief Physician

Yasutomo MIYAJI

Department name	Oncology
Medical School	Kitasato University
Special Qualifications	Board-Certified Internist, Japanese Society of Internal Medicine
Education & Career	March 2013 - Graduated, Kitasato University School of Medicine April 2013 - Miyagi Kosei-kai Saka General Hospital October 2015 - Miyagi Kosei-kai Izumi Hospital April 2016 - Miyagi Kosei-kai Saka General Hospital April 2017 - Joined Kameda Medical Center as Oncology Senior Resident April 2020 - Oncology Staff Physician April 2022 - Chief Physician, Oncology

Staff Physician

Hiroki KONTANI

Subspeciality
Palliative Care

Department name	Oncology
Medical School	Osaka City University
Education & Career	March 2019 - Graduated, Osaka City University School of Medicine April 2019 - National Hospital Organization Tokyo Medical Center April 2021 - Joined Kameda Medical Center as Oncology Resident April 2024 - Oncology Senior Resident April 2025 - Staff Physician, Oncology

Senior Resident

Shiho ITO

Subspeciality
Breast Diseases (mainly Breast Cancer), Endoscopic Breast Surgery

Department name	Oncology
Medical School	Yamagata University
Special Qualifications	Board-Certified Surgeon, Japanese Surgical Society Certified Mammography Reader, Japan Central Organization for Quality Assurance in Breast Cancer Screening
Education & Career	March 2017 - Graduated, Yamagata University School of Medicine April 2017 - Initial Residency, University of Tokyo Hospital April 2019 - Surgical Specialty Residency, University of Tokyo Hospital April 2022 - Staff Physician, Breast Surgery, Kameda Medical Center April 2025 - Senior Resident, Oncology

Internal Medicine Resident

Kotaro MEKARU

Subspeciality
Internal Medicine

Department name	Oncology
Medical School	University of the Ryukyus
Education & Career	March 2021 - Graduated, University of the Ryukyus School of Medicine April 2021 - Initial Residency, Heart Life Hospital, Kariyushi Medical Group April 2023 - Internal Medicine Resident, Oncology, Kameda Medical Center

Internal Medicine Resident

Toshiki OBA

Subspeciality
Hematology, Public Health

Department name	Oncology
Medical School	Kitasato University
Education & Career	March 2021 - Graduated, Kitasato University School of Medicine April 2021 - Initial Residency, Postgraduate Training Center, Kameda Medical Center April 2023 - Internal Medicine Resident, Oncology, Kameda Medical Center

Internal Medicine Resident

Ken FUJIMORI

Subspeciality
General Internal Medicine

Department name	Oncology
Medical School	Yamanashi University
Education & Career	March 2021 - Graduated, University of Yamanashi School of Medicine April 2021 - Yamanashi Prefectural Central Hospital April 2025 - Oncology, Kameda Medical Center

Internal Medicine Resident

Eri KIMURA

Department name	Oncology
Medical School	Yamagata University
Special Qualifications	AHA ACLS Provider AHA BLS Provider Completed Palliative Care Training ICLS Certified JMECC Certified Certified Occupational Physician, Japan Medical Association
Education & Career	March 2022 - Graduated, Yamagata University School of Medicine April 2022 - Kashiwa Municipal Hospital April 2023 - Tokyo University of Science Hospital April 2024 - Oncology, Kameda Medical Center

Internal Medicine Resident

Kanako YOKOMIZO

Subspeciality
Cancer Chemotherapy, General Internal Medicine

Department name	Oncology
Medical School	Shimane University
Special Qualifications	ICLS Certified JMECC Certified
Education & Career	March 2022 - Graduated, Shimane University School of Medicine April 2022 - Tsuyama Central Hospital, Tsuyama Jifukai Foundation April 2024 - Oncology, Kameda Medical Center

Internal Medicine Resident

Nae ITAGAKI

Department name	Oncology
Medical School	Juntendo University
Education & Career	March 2022 - Graduated, Juntendo University School of Medicine April 2022 - Postgraduate Training Center, Kameda Medical Center, Junior Resident April 2024 - Oncology, Kameda Medical Center, Internal Medicine Resident

Internal Medicine Resident (External Training)

Kaho SHIMIZU

Subspeciality
Pulmonology

Department name	Oncology
Medical School	Hirosaki University
Education & Career	March 2023 - Graduated, Hirosaki University School of Medicine April 2023 - Postgraduate Training Center, Kameda Medical Center, Junior Resident April 2025 - Oncology, Kameda Medical Center, Internal Medicine Resident

Internal Medicine Resident

Takumi SANO

Subspeciality
Cancer Genomics

Department name	Oncology
Medical School	Nippon Medical School
Special Qualifications	AHA BLS Provider AHA ACLS Provider
Education & Career	March 2023 - Graduated, Nippon Medical School April 2023 - Postgraduate Training Center, Kameda Medical Center, Junior Resident April 2025 - Oncology, Kameda Medical Center, Internal Medicine Resident

Internal Medicine Resident

Haruki SHIGETA

Subspeciality
Gastroenterology

Department name	Oncology
Medical School	Tohoku University
Education & Career	March 2024 - Graduated, Tohoku University School of Medicine April 2024 - Postgraduate Training Center, Kameda Medical Center, Junior Resident

Resident / Trainee Physician

Tomomi TOBA

Subspeciality
Palliative Care

Department name	Oncology
Medical School	Nihon University
Special Qualifications	Completed the Palliative Care Training Course for Physicians Involved in Cancer and Related Treatments
Education & Career	April 2022 - Graduated, Nihon University School of Medicine April 2022 - Seirei Hamamatsu Hospital April 2024 - Hitachi General Hospital, Hitachinaka April 2025 - Tokyo University of Science Hospital April 2026 - Kameda Medical Center, Oncology Resident

Resident / Trainee Physician

Masayuki MIYATA

Subspeciality
General Internal Medicine

Department name	Oncology
Medical School	Nara Medical University, School of Medicine
Education & Career	March 2022 - Graduated, Nara Medical University, School of Medicine April 2022 - Resident, Nara Medical University Hospital April 2024 - Oncology Resident, Kinki University Hospital April 2025 - Oncology Resident, Kinki University Nara Hospital April 2026 - Kameda Medical Center, Oncology Resident

Resident (External Training)

Ryoji OSHI

Subspeciality
General Internal Medicine, Infectious Diseases, Home Care, Preventive Medicine

Department name	Oncology
Medical School	University of the Ryukyus
Special Qualifications	BLS Provider
Education & Career	March 2024 - Graduated, University of the Ryukyus School of Medicine April 2024 - Joined Kameda Medical Center, Postgraduate Training Center, Junior Resident

Resident / Trainee Physician

Kanako NONAKA

Subspeciality
Genomic Medicine, Intensive Care, Public Health

Department name	Oncology
Medical School	Shimane University
Education & Career	March 2024 - Graduated, Shimane University, School of Medicine April 2024 - Uji Tokushukai Hospital April 2025 - Shimane University Hospital April 2026 - Kameda Medical Center, Oncology Resident

Part-time

Tomohiro ENOKIDA

Department name	Oncology
Medical School	榎田智弘
Special Qualifications	Board-Certified Internist & Specialist, Japanese Society of Internal Medicine Board-Certified Medical Oncologist & Instructor, Japanese Society of Clinical Oncology Certified Oncologist, Japan Board of Cancer Therapy ESMO Certificate in Medical Oncology Doctor of Medicine
Education & Career	March 2007 - Graduated, Miyazaki University, School of Medicine April 2007 - Fukuoka Saiseikai General Hospital, Junior Resident April 2009 - Kameda Medical Center, Oncology Fellow April 2012 - Kameda Medical Center, Part-time Oncology Physician

Yukinori OZAKI

Subspeciality
Chemotherapy

Department name	Oncology
Medical School	Keio University
Education & Career	2008 Mar. Graduate from Keiko University， School of Medicine 2008 Apr. Residency in Tokyo Dental University Ichikawa General Hospital 2010 Apr. Residency in Oncology， Kameda Medical Center 2013 Apr. Department of Oncology， Kameda Medical Center

Part-time

Yoriko HASEGAWA

Department name	Oncology
Medical School	University of Tsukuba
Education & Career	March 2010 - Graduated, University of Tsukuba, School of Medicine April 2010 - Initial Clinical Training, University of Tsukuba Hospital April 2012 - Advanced Clinical Training (Internal Medicine), University of Tsukuba Hospital April 2013 - Joined Kameda General Hospital, Oncology Department, as Senior Resident April 2016 - Part-time, Oncology Department

Part-time

Yumi FUJIMOTO

Subspeciality
Internal Medicine

Department name	Oncology
Medical School	Tokyo University of Science (formerly Tokyo Medical and Dental University)
Education & Career	March 2011 - Graduated, Tokyo University of Science (formerly Tokyo Medical and Dental University) School of Medicine April 2011 - Clinical Training, Ome Municipal General Hospital April 2012 - Clinical Training, Tokyo University of Science Hospital (Formerly TMU Hospital) April 2013 - Joined Kameda General Hospital, Internal Medicine Combined Program, Senior Resident April 2014 - Oncology Department, Senior Resident April 2016 - Part-time, Oncology Department

Part-time

Takao FUJISAWA

Department name	Oncology
Medical School	Kyoto University
Special Qualifications	Board-Certified Internist, Japanese Society of Internal Medicine
Education & Career	March 2011 - Graduated, Kyoto University School of Medicine April 2011 - Clinical Training, Kobe City Medical Center Central Hospital April 2013 - Joined Kameda General Hospital, Oncology Department, Senior Resident April 2016 - Part-time, Oncology Department

Part-time

Nobutaka WATANABE

Subspeciality
General Internal Medicine, General Practice

Department name	Oncology
Medical School	Nippon Medical School
Special Qualifications	Board-Certified Internist, Japanese Society of Internal Medicine Completed Palliative Care Training for Physicians Treating Cancer
Education & Career	March 2018 - Graduated, Nippon Medical School April 2018 - Tokyo Women’s Medical University Hospital April 2020 - Tokyo Bay Urayasu Ichikawa Medical Center April 2024 - Joined Kameda Medical Center, Oncology Department, Senior Resident April 2025 - Instructor, Department of General Medicine, Fujita Medical University May 2025 - Part-time, Oncology Department, Kameda Medical Center