Evidence map›Paper›PMID 40353952›Full record

ArticleBreast cancer (Tokyo, Japan)2025

Impact of the COVID-19 pandemic on breast cancer diagnosis and treatment trends in Japan.

Minoru Miyashita, Hiraku Kumamaru, Naoki Hayashi, Fuyo Kimura, Hiroyuki Yamamoto, Naoki Niikura, Yasuaki Sagara, Hiromitsu Jinno, Masakazu Toi, Shigehira Saji

Abstract readComparative Study
PubMed Full text at PMC Publisher
In one paragraph

Article in Breast cancer (Tokyo, Japan), 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Minoru MiyashitaDepartment of Breast and Endocrine Surgical Oncology, Tohoku University School of Medicine, 1-1 Seiryo-Machi, Aoba-Ku, Sendai, 980-8574, Japan. minoru.miyashita.c6@tohoku.ac.jp.ORCID http://orcid.org/0000-0002-4151-8725
Hiraku KumamaruDepartment of Healthcare Quality Assessment, University of Tokyo, 7-3-1 Hongo, , Bunkyo-Ku, Tokyo, 113-8655, Japan.
Naoki HayashiDivision of Breast Surgical Oncology, Department of Surgery, Showa University School of Medicine, Tokyo, Japan.
Fuyo KimuraDepartment of Breast, Tokyo Medical University Hospital, 6-7-1 Shinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
Hiroyuki YamamotoDepartment of Healthcare Quality Assessment, University of Tokyo, 7-3-1 Hongo, , Bunkyo-Ku, Tokyo, 113-8655, Japan.
Naoki NiikuraDepartment of Breast Oncology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
Yasuaki SagaraDepartment of Breast Surgical Oncology, Social Medical Corporation Hakuaikai, Sagara Hospital, 3-28 Matsubara, Kagoshima, 892-833, Japan.
Hiromitsu JinnoDepartment of Surgery, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8606, Japan.
Masakazu ToiTokyo Metropolitan Komagome Hospital, 3 Chome-18 Honkomagome, Bunkyo City, Tokyo, Japan.
Shigehira SajiDepartment of Medical Oncology, Fukushima Medical University, Fukushima, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThere is no comprehensive report regarding which patient groups were disrupted by the COVID-19 pandemic in Japan having universal health insurance system. To provide the guidance regarding how to act in future pandemics, we investigated the changes in breast cancer (BC) diagnosis and treatment during the COVID-19 pandemic.

methodsThe trends of monthly data were calculated in relation to the variables of a total of 291,018 primary BCs registered on the Japanese National Clinical Database between January 2018 and April 2021.

resultsAn analysis of the nationwide data during the pandemic showed 9% decrease of newly identified BC compared with before the pandemic. The impact was more relevant in the 40-50, 51-60 and 61-70-years age groups (13%, 8% and 9% decrease, respectively). The most substantial reduction was noted in patients identified through screenings without symptoms with a 17% decrease. These effects were also apparent in cT1, cN0, cStage 0, and cStage I (11%, 9%, 8% and 11% decrease, respectively). In breast surgery procedures, there was a notable decrease in breast-conserving surgery (13%) as well as post-operative radiation therapy (11%). During this period, strategies using neoadjuvant endocrine therapy or chemotherapy were implemented to avoid treatment delays for especially Stage I patients (1.5 folds increase).

conclusionsWe have identified the patient groups that are more vulnerable to the effects of the pandemic. The changes during the pandemic might provide the guidance regarding how to act in future emergencies to minimize disadvantages for BC patients.

Indexed as

Breast NeoplasmsCOVID-19Early Detection of CancerMass ScreeningAdultAgedAged, 80 and overAntineoplastic Agents, HormonalChemotherapy, AdjuvantFemaleHealth Services AccessibilityHumansJapanMastectomy, SegmentalMiddle AgedNeoadjuvant TherapyAntineoplastic Agents, HormonalBreast cancerCOVID-19Japanese Breast Cancer SocietyNational clinical databasePandemicRegistry

Identifiers

PMID40353952
PMCPMC12394362

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