#MetaplasticBreastCancer
RPL39 A14V, a risk variant for TNBC overall survival, is observed in 39/40 MpBC vs 0/40 basal-like TNBC
2 intriguing RPL39 downstream
ADAR1 & iNOS 🤠
iNOS IHC expression➡️⏬MpBC overall survival n=40
L-NMMA ⏬MpBC xenograft growth
#JNCI 2016
academic.oup.com/jnci/article...
#MetaplasticBreastCancer
#CaseReport
N=7 MpBC with heterogeneous mesenchymal & matrix components
c-MYC amplification (ISH) in 6/7 cases
#AnnDiagnPathol 2026
www.sciencedirect.com/science/arti...
#MetaplasticBreastCancer
#CaseReport
MpBC with melanocytic components (melanA+S100+HMB45+Sox10+GATA3-)
Non-tolerated immunotherapy (ipilimumab nivolumab) ⏫TIL in melanocytic, not carcinomatous compartment
Mutation
TP53 PIK3CD TSC2 PTCH1
#IntJSurgPathol 2026
journals.sagepub.com/doi/10.1177/...
#MetaplasticBreastCancer #CaseReport
42 y/o
12 x 10.5 x 8 cm recurrent breast mass
Irregular surface
Spindle-cell
p63+PanCK+
Focal myxoid degeneration
Focal osteoclastic giant cells
J Cancer Res Ther 2025
journals.lww.com/cancerjourna...
#MetaplasticBreastCancer
Comparing somatic mutational burden of paired primary tumors vs metastasis
N=17 (8 +lymph node metastasis; 1 +distal metastasis)
Predominantly < 10 mutation/Mb
TP53 PIK3CA PTEM MCL1 MYC
No microsatellite instability
#BreastCancer 2026
www.dovepress.com/clonal-dynam...
#MetaplasticBreastCancer
N=91
21 with immunotherapy
49/58 with genetic testing have no pathogenic mutations!🧐 (On which gene panel?🧐)
61% primary tumors are on left-sided
79% 5-yr overall survival
Baraah Mohamed group #Cureus 2026
www.cureus.com/articles/443...
#MetaplasticBreastCancer
Re-analysis of scRNAseq (CellxGENE)▶️
A small population (7%, 170/3274 cells) of malignant MpBC cells with a hybrid epithelial-phyllodes signature
Love to see IHC validation & spatial omics🧐
#Pharmaceut_MDPI 2026
www.mdpi.com/1424-8247/19...
#MetaplasticBreastCancer
🇸🇪 2008-2018
n=127 MpBC vs n=245 invasive breast cancer of no special type
48 mo f/up
5-yr breast cancer mortality 26% vs 18%
5-yr overall survival 60% vs 75%
Marie Bergman lab #CancerMedicineJ 2026
onlinelibrary.wiley.com/doi/10.1002/...
#MetaplasticBreastCancer
#CaseReport
A 90-gene clinical panel on FFPE section (Ye, J Mol Diagn. 2020), in combination with IHC, to differentiate breast cancers of unknown primary
#cytojournal 2025
cytojournal.com/the-applicat...
#MetaplasticBreastCancer
n=44🇬🇷
YAP/TAZ immunoreactivity in MpBC
Not corr. CTGF CCND1
Not corr. Histological/Molecular subtype
Not corr. Disease-free survival
Marginal corr. Overall survival
Chemo➡️⏫survival
Recurrence➡️⏬ survival HR>100😨
#CurrIssuesMolBiol 2025
www.mdpi.com/1467-3045/47...
#MetaplasticBreastCancer
N=102, 63 mo f/up➡️ 46 recurrence (~90% in 24 mo)🇧🇷
Adjuvant chemotherapy (done in 46% patients)➡️ 3.9-fold ⬆️disease-free survival
Other risk factors - affected lymph nodes, surgical tumor size
No effect - radiotherapy
#FrontOncol 2025
www.frontiersin.org/journals/onc...
#MetaplasticBreastCancer
Spindle cell/Sarcomatous histologic type N=36 is associated with ⏬3-/5-yr Recurrence-free survival & Overall survival
vs other histologic types N=70
MpBC N=106 vs non-Mp TNBC N=106 have similar survival
#CBCjournal 2025
www.clinical-breast-cancer.com/article/S152...
#MetaplasticBreastCancer #Immunotherapy
Pathological complete response was achieved in
1⃣2/33 Neoadjuvant Chemo
2⃣2/7 Neoadjuvant Chemo + Immunotherapy
Love to see some immunopathology on tumor-infiltrating lymphocytes & PD-L1
#BreastCancer 2025
www.dovepress.com/promising-re...
#MetaplasticBreastCancer
Neoadjuvant chemo-immunotherapy response predicts long-term survival
KEYNOTE-522
N=32 stage I-III
high stromal tumor-infiltrating lymphocytes corr. pCR
pCR (n=7)➡️no recurrence
2/3 of residual disease➡️recurrence in 14 mo
#NPJBreastCancer2025
www.nature.com/articles/s41...
#MetaplasticBreastCancer
Non-surgical patient
N=92 + 30
In both cohorts, chemotherapy is associated with improved Overall survival
"Radiotherapy can improve quality of life by alleviating debilitating symptoms" in advanced MpBC
#FrontOncol 2025
www.frontiersin.org/journals/onc...
#MetaplasticBreastCancer
Spindle cell histologic type N=36 is associated with⏬3-/5-yr Recurrence-free survival & Overall survival
vs other histologic types N=70
In this study, MpBC N=106 vs non-Mp TNBC N=106 have similar survival
#ClinBreastCanc 2025
www.clinical-breast-cancer.com/article/S152...
#MetaplasticBreastCancer
TNMpBC-NeoBCSS model predicts 3/5 yr breast cancer-specific survival
C-index 0.82
SEER🇺🇸+🇨🇳
N=1163
Non-metastatic, Tri-Neg, +adjuvant chemo ?radio?🧐
155 +NeoAdj: CR 45 PR 55 NR 55
LASSO regression▶️
NeoAj response
T stage
N stage
#SciRep 2025
www.nature.com/articles/s41...
#MetaplasticBreastCancer #DiffusionWeightedMRI
29🚺
19 squamous + 8 mesenchymal +unclassified histo-type
#ApparentDiffusionCoefficient & tumor size
mesenchymal > squamous
Likely associated with⏬5-y overall/disease-free survival
Dar-Ren Chen lab @plosone.org 2025
journals.plos.org/plosone/arti...
#MetaplasticBreastCancer #CaseReport
70 y/o
Irregular, heavily calcified mass
pT2N1aM0
Lumpectomy
adjuvant Chemo (FEC-Tx) & Radio
2.5 mm carcinoma, 1/9 lymph node invaded, no dist meta
Chondroid differentiation
Lympho-vascular involvement
Ann Med Surg 2025
journals.lww.com/annals-of-me...
Pathogenic Germline Variants in Patients With #MetaplasticBreastCancer
N=143
24 with breast cancer genes
17 BRCA1
5 BRCA2
1 PALB2
1 CHEK
Look forward to #WholeGenomeSequencing for MpBC, both germline & somatic🙏
#JAMANetworkOpen 2025
jamanetwork.com/journals/jam...
#MetaplasticBreastCancer
N=3076 SEER Cohort 2000-2019
Risk factors for Survival
TN MpBC Overall/Breast cancer-specific survival
HR<1
White
Radiotherapy
Chemotherapy (Overall survival only)
HR>1
Age
Tumor stage
Mastectomy
#BMCWomensHealth 2024
bmcwomenshealth.biomedcentral.com/articles/10....
#MetaplasticBreastCancer
A CatBoost model predicts 5-y/o survival MpBC with AUC=0.810
Outperforming RF XGBoost KNN SVM LightGBM
Variable contributions
T stage > N stage > Age > ChemoT > surgery type > M stage > Histo subtype > RadioT
Breast 2024
www.thebreastonline.com/article/S096...
#MetaplasticBreastCancer
Primary👤mammary basal epithelial cell
TGFβ inhibition (A83-01; KO Snai1, Snai2)
⏫Stasis-bypassing into a Pcad+/Ncad+ EMT but⏬metaplastic progenitorness
EZH2 inhibition enforces stasis
#BCRJournal 2024
breast-cancer-research.biomedcentral.com/articles/10....
www.linkedin.com/pulse/galera...
Galera’s Acquisition of Nova Pharmaceuticals Marks Major Shift to Combat Resistant Breast Cancer
kstrategyand.com/pharma-news
#GaleraTherapeutics #NovaPharmaceuticals #BreastCancerResearch #MetaplasticBreastCancer #InvestInCancer #Humanteconomy #Humantec
#MetaplasticBreastcancer Imaging
N=36🇨🇳
Mammography Echo MRI
70% cases exhibit irregular, even spiculated, shape
1/3~1/2 contain calcification
#AcadRadiol 2024
www.sciencedirect.com/science/arti...
#MetaplasticBreastCancer
N=707 N+ (regional lymph node metastasis) cases
SEER database 2000-2015
603 primary
104 secondary
Chemotherapy + radiotherapy
⬇️breast cancer-specific mortality HR=0.71
⬇️non-breast cancer-specific mortality HR=0.32
#FrontOncology 2021
www.frontiersin.org/journals/onc...
#MetaplasticBreastCancer
SEER database 2010-2014
1112 MpBC
21321 Tri-neg #BreastCancer
21~24 mo f/up
Chemotherapy-> No benefit
Radiotherapy-> HR=1.5
Compromised survivals of TN vs non-TN MpBC
Breast Cancer Res Treat 2018
link.springer.com/article/10.1...
#MetaplasticBreastCancer
N=54🇨🇳
51/54 Tri-neg
5-yr Overall Survival 68.5%
Risk factor
Axillary Lymph Node involvement
EGFR
Again, Chemotherapy (anthracycline) is Not independently associated with progression-free survival/PFS (HR=0.79 [0.43-6.33])
#Cytojournal 2024
cytojournal.com/analysis-of-...
#MetaplasticBreastCancer #CaseReport #Immnuotherapy
46y y/o +Lung Metastasis
Primary tumor PD-L1+
15-day #Pembrolizumab + gemcitabine/carboplatin
15-mo survival, lung meta shrunk, kidney meta appear
No germline mutation
Eriko Tokunaga lab Thorac Cancer 2024
onlinelibrary.wiley.com/doi/10.1111/...
Metastatic #MetaplasticBreastCancer DART Trial NCT02834013
Ipilimumab + Nivolumab
Phase II
3/17 (2 Spindle, 1 Chondromyxoid, low tumor mutational burden, microsatellite stable, 2/3 PD-L1-low/neg🧐) achieved durable (28/33/34 mo) Objective Response
#CCR_AACR 2022
aacrjournals.org/clincancerre...
