Evidence map›Paper›PMID 42601812›Full record

ArticleThoracic cancer2026

Exceptional Response of HER2-Positive Breast Cancer to Osimertinib: A Case Report.

Hirotoshi Yasui, Misaki Hatasa, Ko Ohara, Kaito Sano, Yasutaka Mori, Tomofumi Shibata, Yasutaka Fukui, Mitsuru Odate, Yoshifumi Arai, Masahiro Fujii and 1 more

Abstract readCase Reports
In one paragraph

Article in Thoracic cancer, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Hirotoshi YasuiDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.ORCID https://orcid.org/0009-0006-6036-2486
Misaki HatasaDepartment of Breast Surgery, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Ko OharaDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Kaito SanoDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.ORCID https://orcid.org/0009-0003-3889-0926
Yasutaka MoriDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Tomofumi ShibataDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Yasutaka FukuiDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Mitsuru OdateDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Yoshifumi AraiDepartment of Clinical Pathology, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.ORCID https://orcid.org/0000-0003-1496-7610
Masahiro FujiiDepartment of Breast Surgery, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.
Yasushi MakinoDepartment of Respiratory Medicine, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Osimertinib is standard therapy for EGFR-mutant lung cancer, and HER2 amplification is a known resistance mechanism. We report HER2-positive breast cancer showing durable regression during osimertinib monotherapy for synchronous EGFR-mutated lung adenocarcinoma. Post-treatment analysis showed marked regression, HER2 amplification, no detectable EGFR, HER2, or PIK3CA mutations, ER/PgR negativity, preserved PTEN, and reduced proliferative activity. These findings suggest ERBB pathway inhibition may have contributed, although the mechanism remains speculative without functional validation. This hypothesis-generating observation describes unexpected breast cancer regression during osimertinib treatment.

Indexed as

AcrylamidesAniline CompoundsBreast NeoplasmsErb-b2 Receptor Tyrosine KinasesFemaleHumansIndolesPyrimidinesAcrylamidesAniline CompoundsERBB2 protein, humanErb-b2 Receptor Tyrosine KinasesIndolesosimertinibPyrimidinesbreast cancerEGFR lung cancerERBB signalingHER2 amplificationosimertinib

Identifiers

PMID42601812
PMCPMC13476526

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.