Evidence map›Paper›PMID 42142352›Full record

ArticleThe American journal of case reports2026

Long-Term Response to Pembrolizumab in Metastatic Metaplastic Breast Carcinoma: A Case Report.

Yuki Oshima, Takamasa Suzuki, Yumi Fukaya, Keiko Hosoya, Yuko Tanaka, Makoto Wakahara, Yoshihisa Umekita, Yugo Tanaka

Abstract readCase Reports
In one paragraph

Article in The American journal of case reports, 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

8 authors.

Yuki OshimaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Takamasa SuzukiDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Yumi FukayaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Keiko HosoyaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Yuko TanakaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Makoto WakaharaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Yoshihisa UmekitaDepartment of Pathology, Division of Pathology, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Yugo TanakaDepartment of Surgery, Division of General Thoracic Surgery and Breast and Endocrine Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BACKGROUND Metaplastic breast carcinoma (MpBC), a rare subtype of breast malignancy characterized by low response rates to conventional chemotherapy, often presents as triple-negative breast cancer (TNBC). Recently, systemic therapy including immune checkpoint inhibitors (ICIs) has emerged as a promising treatment option for TNBCs in perioperative or metastatic settings. However, evidence regarding the efficacy of ICIs for MpBC remains limited. CASE REPORT A 52-year-old Japanese woman underwent radical surgery for primary MpBC of the breast, which confirmed the triple-negative subtype. Despite adjuvant chemotherapy with epirubicin and cyclophosphamide, metastases to the sternum and lungs developed during treatment. Because the initial surgical specimen was PD-L1-positive, the treatment was changed to chemoimmunotherapy consisting of pembrolizumab, gemcitabine, and carboplatin based on the KEYNOTE-355 trial. Although the precordial mass and multiple lung metastases temporarily increased in size soon after treatment initiation, the metastatic lesions subsequently showed marked shrinkage. The patient developed treatment-related adrenal insufficiency, rash, pruritus, and anemia, all categorized as Grade 2. Hydrocortisone replacement therapy was initiated for adrenal insufficiency, while pembrolizumab was continued without interruption. Ten months after treatment initiation, carboplatin plus gemcitabine was discontinued because of adverse events, including myelosuppression, and the patient was transitioned to pembrolizumab monotherapy. At 30 months after the initiation of chemoimmunotherapy, PET/CT showed only mild ¹⁸F-fluorodeoxyglucose uptake in the sternal metastasis, with no evidence of disease progression. CONCLUSIONS This report describes the successful treatment of metastatic MpBC with pembrolizumab-containing chemoimmunotherapy. Pembrolizumab combination therapy may be a promising treatment option for metastatic MpBC.

Indexed as

Antibodies, Monoclonal, HumanizedAntineoplastic Agents, ImmunologicalBreast NeoplasmsLung NeoplasmsTriple Negative Breast NeoplasmsFemaleHumansMiddle AgedAntibodies, Monoclonal, HumanizedAntineoplastic Agents, Immunologicalpembrolizumab

Identifiers

PMID42142352
PMCPMC13189029

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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.