16 May 2026
: Case report 
Long-Term Response to Pembrolizumab in Metastatic Metaplastic Breast Carcinoma: A Case Report
Unusual clinical course, Unusual or unexpected effect of treatment
Yuki Oshima ABCDEF 1, Takamasa Suzuki D 1, Yumi Fukaya D 1, Keiko Hosoya D 1, Yuko Tanaka D 1, Makoto Wakahara ABCDEF 1*, Yoshihisa Umekita CD 2, Yugo Tanaka ABCDEF 1DOI: 10.12659/AJCR.952330
Am J Case Rep 2026; 27:e952330
Figure 1 Pretreatment imaging. Magnetic resonance imaging revealing a tumor measuring 5.9×5.8×4.5 cm, with suspected invasion into the pectoralis major muscle.