Progression-Free Survival and Time to Progression as Real Surrogate End Points for Overall Survival in Advanced Breast Cancer: A Meta-Analysis of 37 Trials

Patient eligibility for trials with imaging response assessment at the time of molecular tumor board presentation

PURPOSE

To assess the eligibility of patients with advanced or recurrent solid malignancies presented to a molecular tumor board (MTB) at a large precision oncology center for inclusion in trials with the endpoints objective response rate (ORR) or duration of response (DOR) based on Response Evaluation Criteria in Solid Tumors (RECIST version 1.1).

METHODS

Prospective patients with available imaging at the time of presentation in the MTB were included. Imaging data was reviewed for objectifiable measurable disease (MD) according to RECIST v1.1. Additionally, we evaluated the patients with MD for representativeness of the identified measurable lesion(s) in relation to the overall tumor burden.

RESULTS

262 patients with different solid malignancies were included. 177 patients (68%) had MD and 85 (32%) had non-measurable disease (NMD) at the time point of MTB presentation in accordance with RECIST v1.1. MD was not representative of the overall tumor burden in eleven patients (6%). The main reasons for NMD were lesions with longest diameter shorter than 10 mm (22%) and non-measurable peritoneal carcinomatosis (18%). Colorectal cancer and malignant melanoma displayed the highest rates of MD (> 75%). In contrast, gastric cancer, head and neck malignancies, and ovarian carcinoma had the lowest rates of MD (< 55%). In case of MD, the measurable lesions were representative of the overall tumor burden in the vast majority of cases (94%).

CONCLUSION

Approximately one third of cancer patients with advanced solid malignancies are not eligible for treatment response assessment in trials with endpoints ORR or DOR at the time of MTB presentation. The rate of patients eligible for trials with imaging endpoints differs significantly based on the underlying malignancy and should be taken under consideration during the planning of new precision oncology trials.

Nomograms Predict PFS and OS for SCLC Patients After Standardized Treatment: A Real-World Study

Purpose

This study aims to investigate the process of small cell lung cancer (SCLC) patients from achieving optimal efficacy to experiencing disease progression until death. It examines the predictive value of the treatment response on progression free survival (PFS) and overall survival (OS) of SCLC patients.

Patients and Methods

We conducted a retrospective analysis on 136 SCLC patients diagnosed from 1992 to 2018. Important prognostic factors were identified to construct nomogram models. The predictive performance of the models was evaluated using the receiver operating characteristic curves and calibration curves. Survival differences between groups were compared using Kaplan-Meier survival curves. Subsequently, an independent cohort consisting of 106 SCLC patients diagnosed from 2014 to 2021 was used for validation.

Results

We constructed two nomograms to predict first-line PFS (PFS1) and OS of SCLC. The area under the receiver operating characteristic curves for the PFS1 nomogram predicting PFS at 3-, 6-, and 12-months were 0.919 (95% CI: 0.867-0.970), 0.908 (95% CI: 0.860-0.956) and 0.878 (95% CI: 0.798-0.958), and for the OS nomogram predicting OS at 6-, 12-, and 24-months were 0.814 (95% CI: 0.736-0.892), 0.819 (95% CI: 0.749-0.889) and 0.809 (95% CI: 0.678-0.941), indicating those two models with a high discriminative ability. The calibration curves demonstrated the models had a high degree of consistency between predicted and observed values. According to the risk scores, patients were divided into high-risk and low-risk groups, showing a significant difference in survival rate. And these findings were validated in another independent validation cohort.

Conclusion

Based on the patients' treatment response after standardized treatment, we developed and validated two nomogram models to predict PFS1 and OS of SCLC. The models demonstrated good accuracy, reliability and clinical applicability by validating in an independent cohort.

Correlation between pathologic complete response, event-free survival/disease-free survival and overall survival in neoadjuvant and/or adjuvant HR+/HER2-breast cancer

Purpose

The study's purpose was to evaluate the correlation between overall survival (OS) and its potential surrogate endpoints: pathologic complete response (pCR) and event-free survival (EFS)/disease-free survival (DFS) in neoadjuvant and/or adjuvant HR+/HER2- breast cancer.

Methods

Systematic search was performed in MEDLINE, EMBASE, Cochrane Library databases and other relevant sources to identify literature that have reported outcomes of interest in the target setting. The strength of correlation of EFS/DFS with OS, pCR with OS, and pCR with EFS/DFS was measured using Pearson's correlation coefficient (r) based on weighted regression analysis. For Surrogate Endpoint-True Endpoint pairs where correlation was found to be moderate, surrogate threshold effect (STE) was estimated using a mixed-effects model. Sensitivity analyses were conducted on the scale and weights used and removing outlier data.

Results

Moderate correlation was observed of relative measures [log(HR)] of EFS/DFS and OS (r = 0.91; 95% CI: 0.83, 0.96, p < 0.0001). STE for HR_EFS/DFS was estimated to be 0.73. Association between EFS/DFS at 1, 2 and 3 years with OS at 4- and 5-year landmarks was moderate. Relative treatment effects of pCR and EFS/DFS were not strongly associated (r: 0.24; 95% CI: -0.63, 0.84, p = 0.6028). Correlation between pCR and OS was either not evaluated due to inadequate sample size (relative outcomes) or weak (absolute outcomes). Results obtained in the sensitivity analyses were similar to base scenario.

Conclusion

EFS/DFS were moderately correlated with OS in this trial-level analysis. They may be considered as valid surrogates for OS in HR+/HER2- breast cancer.

Anti-HER2 antibody prolongs overall survival disproportionally more than progression-free survival in HER2-Positive metastatic breast cancer patients

Background

This meta-analysis aimed to test the hypothesis that the HER2-positive metastatic breast cancer (mBC) patients treated with anti-HER2 antibodies in trial intervention arms have a greater prolongation of overall survival (OS) than of progression-free survival (PFS) and this extra-prolongation of median survival time in OS relates specifically to the anti-HER2 antibody.

Methods

The NCBI/Pubmed and Cochrane databases were searched systematically for HER2-positive or mBC trials published in English during January 1999–November 2017. Treatment arms with shorter PFS were considered as the “control” arm, whereas those with longer PFS as the “test” arm. The between-treatment drug differences were grouped into nine categories. Groups with or without anti-HER2 antibodies were pooled respectively for comparisons. The interrelationships between PFS and OS hazard ratios (HRs) and median survival time differences were investigated by conducting fixed-effects and mixed-effects linear meta-regression analyses.

Results

Twenty-eight trials (10,928 patients) from 438 articles were collected, and four with missing data were excluded in meta-regression analysis. Overall median PFS (HR = 0.73, 95% CI: 0.68–0.78) and median OS (HR = 0.82, 95% CI: 0.77–0.87) weakly favored the longer PFS arm with a weak correlation between the PFS and OS HRs. However, the between-treatment drug difference was anti-HER2 antibody, the absolute increment in median OS time was double that of median PFS time (p < 0.001) and linearly correlated, which was not found with any non-anti-HER2 antibody drug differences.

Conclusions

Anti-HER2 antibody in patients with HER2-positive mBC prolonged OS more than PFS and mandates further investigation.

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Our study dissected the overall survival benefit over progression-free survival in HER-2 positive metastatic breast cancer treated with anti-HER2 antibody by meta-analysis.

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Use of anti-HER2 antibodies, but not other anticancer drugs, to treat HER2-positive metastatic breast cancer independently predicted the OS compared with PFS.

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The design of future clinical trials should consider anti-HER2 antibodies carefully in the treatment armamentarium for HER2-positive metastatic breast cancer.

Definition and risk factors of early recurrence based on affecting prognosis of esophageal squamous cell carcinoma patients after radical resection

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21 months was defined as the optimal threshold of RFS for dividing patients into early and late recurrence according to the influence on OS by minimum P-value method.

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Primary tumor location, pathological T stage, positive lymph nodes, and TLNs were shown to be independently associated with early recurrence.

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For the late recurrent patients, there was a significant survival advantage after recurrence for concurrent chemoradiotherapy than sequential chemoradiotherapy and radiotherapy alone.

Early recurrence after surgery could affect cancerous patients’ prognosis, but the definition of early recurrence and its risk factors for esophageal squamous cell carcinoma (ESCC) patients are still unclear. This study analyzed the clinical data of 468 post-surgery recurrent ESCC patients retrospectively. A minimum p-value approach was used to evaluate the optimal cut-off value of recurrence free survival (RFS) to define early recurrence. Risk factors of early recurrence were developed based on a Cox model. The optimal cut-off value of RFS to distinguish early recurrence was 21 months (p <0.001). Independent risk factors for early recurrence included tumor locations (HR=0.562, p <0.001), pathological T stage (HR=1.829, p <0.001), tumor diameter (HR=1.344, p = 0.039), positive lymph nodes (HR=1.361, p <0.001), and total resected lymph nodes (HR=1.271, p = 044). For the late recurrent patients, there was a much more significant survival advantage for recurrence after concurrent chemoradiotherapy than that after sequential chemoradiotherapy and radiotherapy alone (p = 0.0066). In conclusion, this study defined 21 months of RFS as early recurrence and also identified its risk factors. Concurrent chemoradiotherapy was suggested as preferred post-relapse treatment for late recurrent ESCC patients.

Meta-analyses on progression-free survival as a surrogate endpoint for overall survival in triple-negative breast cancer

PURPOSE

Earlier studies suggest progression-free survival (PFS) may be used as a surrogate endpoint for overall survival (OS) in metastatic breast cancer, which could shorten follow-up duration and speed up assessment of treatment effects. However, to our knowledge, the association between them is still unclear in advanced or metastatic triple-negative breast cancer (TNBC).

METHODS

A literature-based meta-analysis followed by correlation analysis was conducted in advanced or metastatic TNBC. Weighted multiple regression analysis was then used to test the strength of the association between medians of PFS and OS, and the association between HR_PFS and HR_OS.

RESULTS

Fourteen randomized clinical trials published between January 2007 and August 2019, 31 median pairs for PFS and OS, and 17 pairs for HR_PFS and HR_OS from 3,880 patients were selected. The Pearson correlation coefficient between medians of PFS and OS was 0.84 (95% confidence interval (CI) 0.68-0.92, p < 0.001), and the correlation coefficient between HR_PFS and HR_OS was 0.86 (95% CI 0.63-0.95, p < 0.001). Weighted multiple regression analysis showed HR_PFS was the most significant predictor of HR_OS among covariates analyzed (p < 0.001). Both the medians of PFS and OS correlation, and the HR_PFS and HR_OS correlation were 0.79 (p < 0.001), 0.80 (p = 0.001), respectively, in the 11 trials excluding immunotherapy and bevacizumab-based therapy trials.

CONCLUSIONS

Our analysis suggests PFS can be strongly correlated with OS and considered a valid surrogate endpoint for OS in advanced or metastatic TNBC.

Evaluating the evidence behind the surrogate measures included in the FDA's table of surrogate endpoints as supporting approval of cancer drugs

BACKGROUND

In July 2018, the FDA first published a table listing all surrogate measures that it has used, and may accept for future use, in regulatory approval. However, the strength of surrogacy for those measures was not formally assessed. Using the case example of breast cancer, we aimed to evaluate the strength of correlation of surrogate measures listed in the FDA's Table with overall survival.

METHODS

This cross-sectional study of the FDA's Table of Surrogate Endpoints was conducted in May 2019. All surrogate measures listed in the FDA table as appropriate for accelerated or regular approval for breast cancer were extracted. We identified studies evaluating the correlation of treatment benefit in the surrogate with treatment benefit in overall survival and extracted results from the correlation analysis.

FINDINGS

Five surrogate endpoints were listed for breast cancer in the FDA website: pathological complete response rates (pCR), event-free survival (EFS), disease-free survival (DFS), objective response rates (ORR), and progression-free survival (PFS), of which pCR was listed as appropriate only for accelerated approval, while the rest were considered appropriate for accelerated or regular approval. No correlation study evaluated the correlation of treatment effects on EFS with that on OS. The results from correlation studies evaluating pCR, DFS, ORR, and PFS suggest that the treatment effects on none of these surrogate measures were strongly correlated with treatment effects on OS (r<0.85 or R²  < 0.7, except for DFS in HER2 positive early breast cancer (R²  = 0.75).

INTERPRETATION

Using breast cancer as an example, we evaluated the underlying evidence for the surrogate endpoints for solid tumors listed in the FDA's Table of Surrogate Endpoints and found weak or missing correlations of treatment effects on these surrogates with treatment effects on OS . Surrogate measures should be predictive of clinical benefit to be useful in supporting regular FDA approval.

FUNDING

Work on this project was funded by the Arnold Ventures. Dr. Kesselheim is also supported by the Harvard-MIT Center for Regulatory Science. The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Endocrine treatment versus chemotherapy in postmenopausal women with hormone receptor-positive, HER2-negative, metastatic breast cancer: a systematic review and network meta-analysis

BACKGROUND

Although international guidelines support the administration of hormone therapies with or without targeted therapies in postmenopausal women with hormone-receptor-positive, HER2-negative metastatic breast cancer, upfront use of chemotherapy remains common even in the absence of visceral crisis. Because first-line or second-line treatments, or both, based on chemotherapy and on hormone therapy have been scarcely investigated in head-to-head randomised controlled trials, we aimed to compare these two different approaches.

METHODS

We did a systematic review and network meta-analysis with a systematic literature search on PubMed, Embase, Cochrane Central Register of Clinical Trials, Web of Science, and online archives of the most relevant international oncology conferences. We included all phase 2 and 3 randomised controlled trials investigating chemotherapy with or without targeted therapies and hormone therapies with or without targeted therapies as first-line or second-line treatments, or both, in postmenopausal women with hormone-receptor-positive, HER2-negative metastatic breast cancer, published between Jan 1, 2000, and Dec 31, 2017. Additional recently published randomised controlled trials relevant to the topic were also subsequently added. No language restrictions were adopted for our search. A Bayesian network meta-analysis was done to compare hazard ratios (HRs) for progression-free survival (the primary outcome), and to compare odds ratios (ORs) for the proportion of patients achieving an overall response (the secondary outcome). All treatments were compared to anastrozole and to palbociclib plus letrozole. This study is registered in the Open Science Framework online public database, registration DOI 10.17605/OSF.IO/496VR.

FINDINGS

We identified 2689 published results and 140 studies (comprising 50 029 patients) were included in the analysis. Palbociclib plus letrozole (HR 0·42; 95% credible interval [CrI] 0·25-0·70), ribociclib plus letrozole (0·43; 0·24-0·77), abemaciclib plus anastrozole or letrozole (0·42; 0·23-0·76), palbociclib plus fulvestrant (0·37; 0·23-0·59), ribociclib plus fulvestrant (0·48; 0·31-0·74), abemaciclib plus fulvestrant (0·44; 0·28-0·70), everolimus plus exemestane (0·42; 0·28-0·67), and, in patients with a PIK3CA mutation, alpelisib plus fulvestrant (0·39; 0·22-0·66), and several chemotherapy-based regimens, including anthracycline and taxane-containing regimens, were associated with better progression-free survival than was anastrozole alone. No chemotherapy or hormone therapy regimen was significantly better than palbociclib plus letrozole for progression-free survival. Paclitaxel plus bevacizumab was the only clinically relevant regimen that was significantly better than palbociclib plus letrozole in terms of the proportion of patients achieving an overall response (OR 8·95; 95% CrI 1·03-76·92).

INTERPRETATION

In the first-line or second-line setting, CDK4/6 inhibitors plus hormone therapies are better than standard hormone therapies in terms of progression-free survival. Moreover, no chemotherapy regimen with or without targeted therapy is significantly better than CDK4/6 inhibitors plus hormone therapies in terms of progression-free survival. Our data support treatment guideline recommendations involving the new combinations of hormone therapies plus targeted therapies as first-line or second-line treatments, or in both settings, in women with hormone-receptor-positive, HER2-negative metastatic breast cancer.

FUNDING

None.

Evaluation of MET T1010I and MET rs40239 single-nucleotide polymorphisms in triple-negative breast cancer: a case-control study

Aim: The purpose of this study is to evaluate the role of MET T1010I and MET rs40239 as potential risk factor and/or prognostic markers in patients with triple-negative breast cancer (TNBC).

Methods: 114 samples of DNA from paraffin-embedded breast normal tissues of patients with TNBC and 124 samples of healthy controls were collected and analyzed for MET T1010I and MET rs40239 polymorphisms.

Results: MET T1010I CT genotype was associated with increased risk of TNBC in both univariate and multivariate analysis. The status of rs40239 was not associated with a higher risk for TNBC at either the univariate or the multivariate analysis. None of the examined polymorphisms was associated with overall survival at the univariate or multivariate Cox regression analysis (adjusted HR=1.35, 95% CI: 0.31–5.97 for MET T1010I CT/TT vs CC; adjusted HR=1.78, 95% CI: 0.73–4.35 for rs40239 AG/GG vs AA).

Conclusion: Our case–control study suggests that MET T1010I seems to be a risk factor for TNBC in the Caucasian Greek population, in contrast with MET rs40239, where no correlation was found.

Chemotherapy Modulates Endocrine Therapy-Related Resistance Mutations in Metastatic Breast Cancer

PURPOSE: Accumulation of PIK3CA, ESR1, and GATA3 mutations results in resistance to endocrine therapy in breast cancer patients; however, the response of these genes to chemotherapy is unclear. Therefore, we sought to evaluate the genetic response of circulating tumor DNA (ctDNA) to chemotherapy in metastatic breast cancer patients. METHODS: The mutation frequency of 1021 genes was examined prior to chemotherapy in ctDNA of 44 estrogen receptor–positive metastatic breast cancer patients. These genes were evaluated again in a subset of patients (n=24) following chemotherapy. Mutation frequency was defined as the percentage of mutations found in ctDNA compared to total cell-free DNA. RESULTS: Prior to chemotherapy, PIK3CA was the most commonly mutated gene, with mutation found in 22 of the metastatic breast cancer patients. Following chemotherapy, 16 patients exhibited progressive disease (PD), and 8 patients experienced no progression (non-PD). PIK3CA mutation frequency increased in 56.25% (9/16) of the PD patients but decreased in 62.5% (5/8) of the non-PD patients. As a result, more PD patients exhibited increased PIK3CA mutation frequency than non-PD patients (56.25% vs 0%, P=.002). Further, ESR1 and GATA3 mutations correlated with PIK3CA mutation. Interestingly, patients receiving the mTOR inhibitor everolimus exhibited a lower progression rate (0% vs 62.5%, P=.001), and the combination of everolimus and chemotherapy effectively suppressed PIK3CA, ESR1, and GATA3 gene mutations. CONCLUSION: Together, these results suggest that mTOR inhibition may be a useful chemotherapy adjuvant to suppress chemotherapy-induced gene mutations that render tumors resistant to endocrine therapy in metastatic breast cancer patients with PD.

Trends in endpoint selection and result interpretation in advanced non-small cell lung cancer clinical trials published between 2000 and 2012: A retrospective cohort study

Background

The objective of this review was to investigate trends in clinical trial design, specifically, the primary outcomes used, interpretation of results, and the magnitude of the benefits described in phase III controlled clinical trials in the first‐line treatment of patients with advanced non‐small cell lung cancer (NSCLC).

Methods

Seventy‐six trials published between 2000 and 2012 were selected from a total of 122 identified in a structured search.

Results

Overall survival (OS) was evaluated as the primary study endpoint in 50 (65.8%) trials, followed by progression‐free survival (PFS) in 15 (19.7%), and other variables, such as toxicity, quality of life (QoL), and response rate in 11 (14.5%). Ten (66.7%) out of 15 clinical trials using PFS as the primary endpoint were published between 2010 and 2012. Median overall survival (mOS) was 9.90 months (interquartile range: 3.5) with an increase of 0.384 months per year of publication (P < 0.001). A statistically significant improvement in mOS was obtained in only 13 (18.8%) trials. A total of 41 (53.9%) studies concluded that the result was positive. Of these, only 16 (39.1%) showed a statistically significant benefit in OS. QoL was assessed in 46 trials (60.5%) and of these, 10 (21.7%) reported significant improvements.

Conclusions

These findings raise important questions about how clinical benefits are measured in clinical trials in advanced NSCLC. Appropriate clinically relevant outcome variables should be established and validated, and post‐marketing studies should be requested by regulatory authorities to ensure meaningful clinical benefits in OS and QoL.

Clinical and genetic risk factors for Fulvestrant treatment in post-menopause ER-positive advanced breast cancer patients

Background

Among breast cancer (BC) patients, near 40% are post-menopause, and 70%–80% are hormone receptor (HR)-positive. About 30%–40% BC patients who are diagnosed as invasive carcinoma HR-positive BC would eventually develop metastatic breast cancers. In 2016, FALCON trial proves Fulvestrant as an effective first-line endocrine therapy for post-menopause HR-positive advanced BC (ABC) patients. But even after FALCON published, Fulvestrant is rarely used as first-line in real world ABC patients in China.

Method

In this study, 136 Fulvestrant users were enrolled from 2015. To investigate the clinical and genetic risk factors for Fulvestrant treatment response in real world data, biostatistic and bioinformatic analysis tools were adopted.

Result

KM curves showed that Fulvestrant first-line users had a median progression-free survival (mPFS) of 15.67 months, which was longer than the second-line users and third (or higher)-line users (mPFS = 7.47 and 5.43 months, respectively). 16 s (or higher)-line users were voluntarily received circulating tumor DNA (ctDNA) testing after progression. ctDNA testing results showed that compared to patients with PFS longer than 6 months, Fulvestrant users with PFS less than 6 months had a significantly higher mutation rate of ESR1 or ERBB2 gene (0/6 vs 6/10, Fisher’s Exact p-value = 0.03). Multivariate COX regression analysis showed that clinical features, including lymph node metastasis and HER-2 positive, were significant risk factors for poor PFS [hazard ratio (HR) = 2.396 and 2.863, respectively]; high portion of estrogen receptor-positive cells was significant protective factor (HR = 0.663). Propensity-score matching (PMS) analysis suggested that visceral metastasis, prior palliative chemotherapy, and old age at Fulvestrant usage were not significant influential factor for PFS.

Conclusion

First-line Fulvestrant usage could guarantee a better prognosis than higher-line usage. ESR1 or ERBB2 mutation was found to be related to poor PFS in higher-line Fulvestrant users.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1734-x) contains supplementary material, which is available to authorized users.

Identifying Circulating Tumor DNA Mutation Profiles in Metastatic Breast Cancer Patients with Multiline Resistance

Purpose

In cancer patients, tumor gene mutations contribute to drug resistance and treatment failure. In patients with metastatic breast cancer (MBC), these mutations increase after multiline treatment, thereby decreasing treatment efficiency. The aim of this study was to evaluate gene mutation patterns in MBC patients to predict drug resistance and disease progression.

Method

A total of 68 MBC patients who had received multiline treatment were recruited. Circulating tumor DNA (ctDNA) mutations were evaluated and compared among hormone receptor (HR)/human epidermal growth factor receptor 2 (HER2) subgroups.

Results

The baseline gene mutation pattern (at the time of recruitment) varied among HR/HER2 subtypes. BRCA1 and MED12 were frequently mutated in triple negative breast cancer (TNBC) patients, PIK3CA and FAT1 mutations were frequent in HR+ patients, and PIK3CA and ERBB2 mutations were frequent in HER2+ patients. Gene mutation patterns also varied in patients who progressed within either 3 months or 3–6 months of chemotherapy treatment. For example, in HR+ patients who progressed within 3 months of treatment, the frequency of TERT mutations significantly increased. Other related mutations included FAT1 and NOTCH4. In HR+ patients who progressed within 3–6 months, PIK3CA, TP53, MLL3, ERBB2, NOTCH2, and ERS1 were the candidate mutations. This suggests that different mechanisms underlie disease progression at different times after treatment initiation. In the COX model, the ctDNA TP53 + PIK3CA gene mutation pattern successfully predicted progression within 6 months.

Conclusion

ctDNA gene mutation profiles differed among HR/HER2 subtypes of MBC patients. By identifying mutations associated with treatment resistance, we hope to improve therapy selection for MBC patients who received multiline treatment.

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Doctors felt difficult to design effective regimen for MBC patients after multi-line treatment.

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ctDNA testing provide potential treatment targets and reflect treatment response of tumors.

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ctDNA gene mutation pattern varies among four HR/HER2 subgroups.

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The gene mutation patterns also varied between resistant patients and sensitive patients.

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In COX model, ctDNA gene mutation pattern could successfully predict progression within 6 months.

In this study, we clarified the baseline ctDNA mutation pattern for metastatic breast cancer patients. We also selected out treatment-resistance related mutations by ctDNA testing. Here, we showed that PIK3CA were significantly related to HR+.

Moreover, in this study, we also showed a plenty of other rare mutations, including DDR2, CDK12, etc. For different HR/HER2 subtypes, MED12 was frequent in TNBC samples, FAT1 was frequent in HR+ samples, and DDR2 was frequent in HER2+ samples. These findings need further intensive investigations in larger samples.