Koji Oba

9.0k total citations · 3 hit papers
273 papers, 5.7k citations indexed

About

Koji Oba is a scholar working on Oncology, Pulmonary and Respiratory Medicine and Surgery. According to data from OpenAlex, Koji Oba has authored 273 papers receiving a total of 5.7k indexed citations (citations by other indexed papers that have themselves been cited), including 124 papers in Oncology, 98 papers in Pulmonary and Respiratory Medicine and 85 papers in Surgery. Recurrent topics in Koji Oba's work include Colorectal Cancer Treatments and Studies (71 papers), Gastric Cancer Management and Outcomes (65 papers) and Colorectal Cancer Surgical Treatments (42 papers). Koji Oba is often cited by papers focused on Colorectal Cancer Treatments and Studies (71 papers), Gastric Cancer Management and Outcomes (65 papers) and Colorectal Cancer Surgical Treatments (42 papers). Koji Oba collaborates with scholars based in Japan, United States and Belgium. Koji Oba's co-authors include Hideaki Shimada, Junichi Sakamoto, Manabu Ohashi, Yutaka Takahashi, Tamaki Noie, Michiya Kobayashi, Takanori Matsui, Satoshi Morita, Toshio Ogihara and Takao Saruta and has published in prestigious journals such as JAMA, Journal of Clinical Oncology and SHILAP Revista de lepidopterología.

In The Last Decade

Koji Oba

253 papers receiving 5.5k citations

Hit Papers

align trajectories

What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

Effect of Intensive Therapy on the Microvascular Complications of Type 1 Diabetes Mellitus

2002 697 citations Koji Oba profile →
Clinical significance of serum tumor markers for gastric cancer: a systematic review of literature by the Task Force of the Japanese Gastric Cancer Association

2013 393 citations Koji Oba et al. Gastric Cancer profile →
Safety and efficacy of rituximab in systemic sclerosis (DESIRES): a double-blind, investigator-initiated, randomised, placebo-controlled trial

2021 142 citations Koji Oba et al. profile →

Peers

Countries citing papers authored by Koji Oba

Since Specialization

Citations

This map shows the geographic impact of Koji Oba's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Koji Oba with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Koji Oba more than expected).

Fields of papers citing papers by Koji Oba

Since Specialization

Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Koji Oba. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Koji Oba. The network helps show where Koji Oba may publish in the future.

Co-authorship network of co-authors of Koji Oba

This figure shows the co-authorship network connecting the top 25 collaborators of Koji Oba. A scholar is included among the top collaborators of Koji Oba based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Koji Oba. Koji Oba is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

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20 of 20 papers shown

#	Work	Indexed citations
1	A multicenter randomized open-label phase 2 study investigating optimal antiemetic therapy for patients with advanced/recurrent gastric cancer treated with trastuzumab deruxtecan: the EN-hance study 2025 ·International Journal of Clinical Oncology ·Toru Aoyama, Akira Ooki, Koji Oba, Kazuhiro Nishikawa, Ryohei Kawabata, Michitaka Honda, Hiromichi Maeda, Mitsuro Kanda, Keiji Sugiyama, (unknown), Kenki Segami, Masazumi Takahashi, (unknown), Tsutomu Namikawa, (unknown), (unknown), Kazuhito Shiosakai, Junichi Sakamoto	0
2	Association between immune checkpoint inhibitors and uveitis in patients with lung cancer, renal cell carcinoma, or malignant melanoma 2025 ·Canadian Journal of Ophthalmology ·(unknown), (unknown), Akira Okada, (unknown), (unknown), Koji Oba, Yohei Hashimoto, Hideo Yasunaga	0
3	Thermal oxidation of CeB6 single-crystal surfaces: effects on field emission 2025 ·Applied Surface Science ·(unknown), (unknown), Marina Arai, Koji Oba, (unknown), Y. Yamada	0
4	Circulating tumor DNA for predicting radiographic and pathologic response to total neoadjuvant therapy in locally advanced rectal cancer: ENSEMBLE-1. 2024 ·Journal of Clinical Oncology ·Yoshinori Kagawa, Jun Watanabe, (unknown), Koji Ando, Akira Inoue, Yujiro Nishizawa, Yusuke Suwa, Keigo Chida, Tsuyoshi Hata, Yuki Sekido, (unknown), Koichi Okuya, Masaaki Miyo, Koji Oba, George Laliotis, Yoshiaki Nakamura, Hideaki Bando, Takayuki Yoshino, Ichiro Takemasa, Eiji Oki	0
5	Short‐term outcomes of a prospective multicenter phase II trial of total neoadjuvant therapy for locally advanced rectal cancer in Japan (ENSEMBLE‐1) 2023 ·Annals of Gastroenterological Surgery ·Yoshinori Kagawa, Jun Watanabe, Mamoru Uemura, Koji Ando, Akira Inoue, Koji Oba, Ichiro Takemasa, Eiji Oki	5
6	Glycemic Control, Renal Progression, and Use of Telemedicine Phone Consultations Among Japanese Patients With Type 2 Diabetes Mellitus During the COVID-19 Pandemic: Retrospective Cohort Study 2023 ·JMIR Diabetes ·Akiko Sankoda, (unknown), Kayo Waki, (unknown), Koji Oba, Makiko Mieno, Masaomi Nangaku, Toshimasa Yamauchi, Kazuhiko Ohe	2
7	Modification Effects of Albuminuria on the Association Between Kidney Function and Development of Anemia in Diabetes 2023 ·The Journal of Clinical Endocrinology & Metabolism ·Akira Okada, Satoko Yamaguchi, Takahiro Imaizumi, Koji Oba, (unknown), Toshimasa Yamauchi, Takashi Kadowaki, Masaomi Nangaku	2
8	Phase II Study of Continued Trastuzumab Plus Irinotecan in Patients with HER2-positive Gastric Cancer Previously Treated with Trastuzumab (HGCSG 1201) 2022 ·The Oncologist ·Yasuyuki Kawamoto, Satoshi Yuki, Takashi Meguro, Kazuteru Hatanaka, Minoru Uebayashi, Michio Nakamura, Hiroyuki Okuda, Ichiro Iwanaga, Takashi Kato, (unknown), Atsushi Satō, (unknown), Koji Oba, Yuh Sakata, Naoya Sakamoto, Yoshito Komatsu	5
9	Focused Assessment with Sonography for Trauma (FAST) training for first-year resident physicians at a university hospital in Japan: A longitudinal, observational study 2021 ·SHILAP Revista de lepidopterología ·(unknown), Koji Oba, Yuri Ito, (unknown), (unknown), Akira Takasu	2
10	Association between hospital treatment volume and survival of women with gynecologic malignancy in Japan: a JSOG tumor registry-based data extraction study 2021 ·Journal of Gynecologic Oncology ·Hiroko Machida, Koji Matsuo, Koji Oba, Daisuke Aoki, Takayuki Enomoto, Aikou Okamoto, Hidetaka Katabuchi, Satoru Nagase, Masaki Mandai, Nobuo Yaegashi, Wataru Yamagami, Mikio Mikami	5
11	Efficacy and Safety of Polaprezinc (Zinc Compound) on Zinc Deficiency: A Systematic Review and Dose–Response Meta-Analysis of Randomized Clinical Trials Using Individual Patient Data 2020 ·Nutrients ·(unknown), (unknown), Takaki Miwa, Yuji Naito, Koji Oba, Masafumi Sakagami	5
12	Risk factors for outlet obstruction after laparoscopic surgery and diverting ileostomy for rectal cancer 2020 ·Surgery Today ·(unknown), Toshiya Nagasaki, Koji Oba, Takashi Akiyoshi, Toshiki Mukai, Tomohiro Yamaguchi, Yosuke Fukunaga, Yoshiya Fujimoto	21
13	Protocol of the QUATTRO-II study: a multicenter randomized phase II study comparing CAPOXIRI plus bevacizumab with FOLFOXIRI plus bevacizumab as a first-line treatment in patients with metastatic colorectal cancer 2020 ·BMC Cancer ·Masaaki Miyo, Takeshi Kato, Takayuki Yoshino, Takeharu Yamanaka, Hideaki Bando, Hironaga Satake, Kentaro Yamazaki, Hiroya Taniguchi, Eiji Oki, Masahito Kotaka, Koji Oba, Yoshinori Miyata, Kei Muro, Yoshito Komatsu, Hideo Baba, Akihito Tsuji	8
14	Relationship Between the Waiting Times for Surgery and Survival in Patients with Gastric Cancer 2020 ·World Journal of Surgery ·(unknown), Koji Oba, Tsutomu Hayashi, Takanobu Yamada, Kentaro Hara, (unknown), (unknown), (unknown), Shinsuke Nagasawa, Yasushi Rino, Munetaka Masuda, Takashi Ogata, Takaki Yoshikawa, Takashi Oshima	8
15	Association of blood mercury levels during pregnancy with infant birth size by blood selenium levels in the Japan Environment and Children's Study: A prospective birth cohort 2019 ·Environment International ·Sumitaka Kobayashi, Reiko Kishi, Yasuaki Saijo, Yoshiya Ito, Koji Oba, Atsuko Araki, Chihiro Miyashita, Sachiko Itoh, Machiko Minatoya, Keiko Yamazaki, Yu Ait Bamai, Tosiya Sato, Shin Yamazaki, Shoji F. Nakayama, Tomohiko Isobe, Hiroshi Nitta	37
16	Prognostic value of metastatic lymph node regression grade after neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer 2019 ·Surgery ·Tetsuro Tominaga, Takashi Akiyoshi, Noriko Yamamoto, Koji Oba, Toshiya Nagasaki, Tomohiro Yamaguchi, Tsuyoshi Konishi, Yosuke Fukunaga, Masashi Ueno	12
17	Does a laparoscopic approach attenuate the body weight loss and lean body mass loss observed in open distal gastrectomy for gastric cancer? a single-institution exploratory analysis of the JCOG 0912 phase III trial 2017 ·Gastric Cancer ·Toru Aoyama, Tsutomu Sato, Tsutomu Hayashi, Takanobu Yamada, Haruhiko Cho, Takashi Ogata, Koji Oba, Takaki Yoshikawa	14
18	Prospective phase II trial of second-line FOLFIRI in patients with advanced colorectal cancer including analysis of UGT1A1 polymorphisms: FLIGHT 2 study. 2014 ·PubMed ·Keiji Hirata, Naoki Nagata, Takeshi Kato, Yusuke Okuyama, (unknown), Kenichi Takahashi, Koji Oba, Junichi Sakamoto, Shoichi Hazama, Hideyuki Mishima	9
19	1 Trends of Large-scale Clinical Trials of Cardiovascular Diseases in Japan(Clinical Trials Update in Japan and Future Perspective, The 71st Annual Scientific Meeting of the Japanese Circulation Society) 2007 ·Japanese Circulation Journal-english Edition ·Kenji Ueshima, Koji Oba, Kiichiro Tsutani, Kazuwa Nakao	0
20	Studies on the Antianaphylactic Components of Asarum forbesii MAXIM. 1989 ·Koji Oba, Mitsuko Asai, Toshihiro Ishiguro, Toyokazu Kishi, (unknown), Qiang-min Xie	4

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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