Liver Surgery for Breast Cancer That Has Spread to the Liver: What Patients Need to Know

Table of Contents

• Key Points
• Background: Why This Research Matters
• Study Methods: How the Research Was Conducted
• The Studies Included in This Analysis
• Key Findings: Survival Rates at 1, 3, and 5 Years
• Clinical Implications: What This Means for Patients
• Limitations: What This Study Couldn't Prove
• Recommendations: What Patients Should Consider
• Frequently Asked Questions
• Source Information

Key Points

• Meta-analysis of 1,732 patients across 9 studies linked liver resection to 31% lower mortality risk versus no surgery.
• Five-year survival was 46.0% with surgery versus 24.7% without, but no randomized trials were included.
• Likely candidates have few liver lesions, no extrahepatic disease, over 24 months since diagnosis, and non-triple-negative tumors.
• Liver resection was added to systemic therapy, not used instead of it, in the reviewed studies.
• Quality of life and cost were not assessed; surgery is major and requires careful multidisciplinary discussion.

Background: Why This Research Matters

Breast cancer is the most common cancer in women worldwide, with 2.3 million new diagnoses made in 2020. Thanks to improvements in diagnostics, therapeutic strategies, and personalized care, survival rates have improved dramatically — some patients now have anticipated 5-year overall survival rates of 90%. Yet despite these advances, more than 43,000 patients were expected to die from breast cancer in the United States in 2021 alone.

About 6–10% of patients present with metastatic disease (cancer that has spread to other organs) at the time of their initial diagnosis. Additionally, 20–30% of those initially diagnosed with early-stage breast cancer will eventually develop distant metastases. The liver is one of the most common sites for breast cancer to spread, and it is the first site of distant metastasis in 1.0–8.0% of cases.

Historically, breast cancer with liver metastases has been associated with poor outcomes. The estimated 5-year overall survival rate after liver recurrence is just 8.5%. This poor prognosis has led to uncertainty about whether aggressive surgical treatment — removing the liver metastases — can improve outcomes.

In colorectal cancer, liver resection (surgical removal of liver tumors) is well-established as an effective, sometimes curative treatment, and it is recommended in European Society for Medical Oncology (ESMO) guidelines where feasible. However, there is no widely accepted consensus for managing liver metastases that originate from breast cancer. The 4th ESO–ESMO International Consensus Guidelines for Advanced Breast Cancer (ABC4) suggest that local therapy should only be proposed in very carefully selected cases — patients with good performance status, limited liver involvement (no extrahepatic lesions), and demonstrated disease control after adequate systemic therapy. Meanwhile, the National Comprehensive Cancer Network (NCCN) guidelines in the United States do not currently recommend liver resection as a curative option for BCLM at all.

This uncertainty was the driving force behind the current study. The authors set out to systematically review all available evidence and statistically combine the results (a meta-analysis) to determine whether liver resection offers a genuine survival benefit for women with BCLM.

Study Methods: How the Research Was Conducted

This systematic review and meta-analysis was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and MOOSE guidelines — internationally recognized standards for conducting and reporting high-quality research reviews.

The research team searched three major medical databases — PubMed Medline, EMBASE, and Scopus — using a predetermined search strategy. The search terms included combinations such as "breast liver metastases," "breast liver metastases resection," "hepatic metastases," "breast cancer survival," "breast cancer," and "hepatectomy," connected with the Boolean operator "AND." Two independent reviewers performed the search, and a third author was consulted to resolve any disagreements.

Only English-language studies were included, and while the search was not restricted by publication year, only studies published since 2013 were included in the meta-analysis. This deliberate choice reflects the fact that targeted therapeutics have revolutionized breast cancer management in recent years, making older data less relevant to today's treatment landscape. The final search was performed on July 7, 2021.

The study used the PICO framework to define its scope:

• Population: Female patients aged 18 years or older with newly diagnosed, histologically or radiologically confirmed breast cancer liver metastases
• Intervention: Surgical resection (removal) of the liver metastasis with curative intent
• Comparison: No surgical resection of the liver metastasis
• Outcomes: Annual survival rates after BCLM diagnosis, and overall survival expressed as hazard ratios

For statistical analysis, the researchers used the Mantel-Haenszel method to pool survival data as odds ratios (ORs) with 95% confidence intervals (CIs). Either fixed or random effects models were applied depending on whether significant heterogeneity (I² greater than 50%) existed between studies. Hazard ratios (HRs) for overall survival were extracted directly from study tables and text and combined using the generic inverse variance method. All tests were two-tailed, with P values below 0.050 considered statistically significant.

Quality assessment was performed using the Newcastle-Ottawa Scale, a validated tool for evaluating the quality of non-randomized studies. The review identified 2,618 studies in the initial database search. After removing 118 duplicates and 9 non-English articles, and screening titles and abstracts, 125 full-text articles were reviewed. Of these, 69 were excluded for not meeting inclusion criteria, leaving 56 studies for full review. Only 9 studies directly compared survival outcomes between patients who underwent liver resection and those who did not — and these 9 studies formed the basis of the meta-analysis.

The Studies Included in This Analysis

The 9 included studies were published between 2013 and 2020. One-third (3 of 9) were prospective in design (tracking patients forward in time), while the remaining two-thirds (6 of 9) were retrospective (looking back at patient records). The studies came from a variety of countries, including Italy, the United Kingdom, China, the United States, France, Germany, and the Czech Republic.

Here is a breakdown of each study:

• Polistina 2013 (Italy): 12 surgery patients vs. 14 non-surgery patients; mean age 58 years
• Abbas 2017 (United Kingdom): 23 surgery vs. 38 non-surgery; median age 54; median follow-up 48 months
• Feng 2020 (China): 65 surgery vs. 319 non-surgery; median age 50.9; mean follow-up 47 months
• Chun 2020 (USA): 136 surgery vs. 763 non-surgery
• Sadot 2016 (USA): 69 surgery vs. 98 non-surgery; median age 51; mean follow-up 31 months
• Mariani 2013 (France): 51 surgery vs. 51 non-surgery; median age 50
• Dittmar 2013 (Germany): 34 surgery vs. 6 non-surgery; median age 53
• Weinrich 2014 (Germany): 21 surgery vs. 8 non-surgery; median age 55; mean follow-up 22 months
• Treska 2014 (Czech Republic): 13 surgery vs. 11 non-surgery; mean age 50.9

In total, the analysis included 1,732 patients. Of these, 24.5% (424 patients) underwent surgical resection of their liver metastases, while 75.5% (1,308 patients) did not. All patients were female (100%), with a mean age at diagnosis of 52.9 years (ranging from 25 to 94 years).

Twenty-one percent of patients (369 of 1,732) had "synchronous" disease, meaning their liver metastases were discovered within 6 months of their primary breast cancer diagnosis. The remaining patients developed liver metastases later — a condition called "metachronous" disease.

The studies also reported on tumor characteristics. Among the patients for whom data was available:

• Histologic subtype: 285 had ductal carcinoma, 24 had lobular carcinoma, and 9 had other subtypes
• Hormone receptor status: 130 were estrogen receptor positive (ER+), 83 were progesterone receptor positive (PR+), and 66 were HER2 positive (HER2+)

In the Chun 2020 study specifically, 64.7% of surgery patients were ER+, 37.5% were PR+, and 34.6% were HER2+. In the Sadot 2016 study, 66% were ER+, 53% were PR+, and 38% were HER2+.

Key Findings: Survival Rates at 1, 3, and 5 Years

The meta-analysis produced striking results across every time point measured. Here is what the researchers found:

1-Year Survival

Patients who underwent liver resection had significantly better overall survival at 1 year compared with those who did not have surgery. The survival rates were 92.5% (124 of 134 patients) for the surgery group versus 79.7% (311 of 390 patients) for the non-surgery group — a difference that was statistically significant (P < 0.001). At meta-analysis, the odds ratio for mortality was 0.26 (95% CI: 0.12–0.55, P = 0.0004, I² = 32%), meaning surgery patients were about 74% less likely to die within the first year.

Individual study results at 1 year varied widely. In the Polistina 2013 study, 100% of surgery patients survived to 1 year versus 64.3% of non-surgery patients. In the Weinrich 2014 study, the gap was even larger: 85.7% versus 37.5%. Interestingly, in the Treska 2014 study, the non-surgery group actually did slightly better at 1 year (90.9% vs. 76.9%), though the group sizes were very small (11 and 13 patients, respectively).

3-Year Survival

At 3 years, the survival advantage for surgery remained substantial: 81.9% (123 of 152) of surgery patients were alive versus 47.0% (197 of 419) of non-surgery patients (P < 0.001). However, at meta-analysis, the difference in mortality did not reach statistical significance (OR: 0.32, 95% CI: 0.09–1.12, P = 0.070, I² = 77%).

The authors note that the high heterogeneity (I² = 77%) at this time point likely reflects the wide variation in patient outcomes across studies. For example, in the Mariani 2013 study, 80.4% of surgery patients survived to 3 years versus 51.0% of non-surgery patients. In the Feng 2020 study (the largest contributor to the non-surgery group at 76.1%), 83.1% of surgery patients survived versus 42.9% of non-surgery patients. But in the Treska 2014 study, the non-surgery group again appeared to do better (81.8% vs. 46.2%), likely due to small sample sizes and differing patient characteristics.

5-Year Survival

At 5 years, the survival benefit of surgery was again clearly evident. 46.0% (162 of 352) of surgery patients were alive versus just 24.7% (309 of 1,249) of non-surgery patients (P < 0.001). At meta-analysis, patients who underwent surgery were significantly less likely to die (OR: 0.46, 95% CI: 0.25–0.87, P = 0.020, I² = 70%).

Notable individual study results at 5 years include:

• Feng 2020: 58.5% surgery survival vs. 27.9% non-surgery
• Chun 2020: 52.9% vs. 21.0% (the largest study, with 136 surgery and 763 non-surgery patients)
• Polistina 2013: 33.3% vs. 14.3%
• Abbas 2017: 52.2% vs. 47.4%
• Sadot 2016: 37.7% vs. 38.8% (one of the few studies showing no benefit)

Together, the Feng 2020 and Chun 2020 studies accounted for 86.6% of the non-surgery patients in the 5-year analysis, giving them substantial weight in the pooled result.

Overall Survival (Hazard Ratio Analysis)

Using a different statistical approach — the generic inverse variance method applied to hazard ratios — the researchers found that patients who underwent surgery were likely to have significantly better overall survival across the entire study period. The pooled hazard ratio was 0.69 (95% CI: 0.59–0.80, P < 0.001, I² = 21%). In plain terms, this means surgery patients had a 31% lower risk of dying at any point during follow-up compared with those who did not have surgery. The low heterogeneity (I² = 21%) at this analysis level indicates good consistency across studies. The mean follow-up across studies was 37 months (just over 3 years).

Clinical Implications: What This Means for Patients

This study provides the most comprehensive evidence to date that liver resection may offer a genuine survival advantage for women with breast cancer liver metastases. The authors note that breast cancer is among the leading causes of liver metastases for non-colorectal, non-neuroendocrine cancers, yet only about 1.8% of all liver resections are currently performed for breast cancer secondaries. This reluctance to operate stems largely from the fact that fewer than 8% of patients with metastatic breast cancer have disease confined to the liver alone — for the rest, the cancer has spread elsewhere, making surgery on the liver potentially less beneficial.

The study's findings are particularly relevant given that an estimated 1–10% of patients with newly diagnosed BCLM have "potentially curable" stage 4 disease. For these carefully selected patients, aggressive multidisciplinary treatment — including surgical resection plus systemic therapy — may offer the best chance at long-term survival.

Who Might Benefit Most?

The researchers highlighted several factors that previous studies have associated with better outcomes after liver resection for BCLM:

• Negative axillary lymph nodes at the time of the original breast surgery
• Solitary liver lesions (a single metastasis rather than multiple)
• A gap of more than 24 months between the primary breast cancer diagnosis and the appearance of liver metastases
• A complete surgical resection (known as "R0 resection," meaning no cancer cells remain at the margins of the removed tissue)

These factors come from a 2020 meta-analysis by Galiandro and colleagues, and the current authors recommend that they be considered carefully in multidisciplinary team discussions.

Conversely, certain factors are associated with poorer outcomes after surgery. These include:

• Extrahepatic disease (cancer spread beyond the liver) — one study of 34 patients found that extrahepatic metastases was the only prognostic factor significantly associated with reduced survival
• Triple-negative breast cancer — one study reported poorer survival outcomes among triple-negative patients undergoing liver surgery
• Higher numbers of metastatic lesions in the liver
• Younger age at diagnosis

That said, the authors point out that some studies have suggested surgery may still be considered in patients with stable extrahepatic metastases or resectable intra-abdominal metastases. This is an area of active debate, and decisions must be individualized.

The Context of Modern Systemic Therapy

One important observation from this study: the pooled 5-year overall survival for patients treated with systemic therapy alone (without surgery) was only 24.7%. This is surprising in the modern era, where patients with estrogen receptor-positive or HER2-positive metastatic disease can often expect median survival to reach or exceed 5 years. The authors suggest this relatively poor outcome for the non-surgery group may reflect that some of these patients had more advanced or aggressive disease that made them unsuitable for surgery in the first place — a concept known as "selection bias." This is a key reason why the results should be interpreted cautiously.

Limitations: What This Study Couldn't Prove

While these results are encouraging, the authors are transparent about several important limitations:

• No randomized controlled trials: None of the 9 included studies were randomized, meaning patients were not randomly assigned to surgery versus no surgery. This introduces the potential for selection bias — patients who had surgery may have been healthier, had less extensive disease, or been better candidates for surgery in other ways. It also introduces ascertainment and confounding biases.
• Significant heterogeneity: The studies varied considerably in their designs, patient populations, and treatment approaches. This heterogeneity (particularly at the 3-year time point, with I² = 77%) reduces the reliability of some pooled estimates.
• Varied treatment approaches: The management strategies for the non-surgery group varied across studies. Some patients received chemotherapy, others hormonal therapy, and treatment protocols were not standardized.
• Different surgical techniques: The surgeries performed varied across institutions, which could affect outcomes.
• Missing clinicopathological data: There was no data available to directly compare the impact of patient age, gender (all were female in this study), comorbidities, or hormone receptor status on treatment outcomes.
• No data on post-metastasis therapies: The analysis did not explore what treatments patients received after their metastases were diagnosed, which limits the conclusions that can be drawn about the specific contribution of surgery.
• Limited recurrence data: Very little data was available on cancer recurrence following liver resection.
• Quality of life and cost not addressed: The study did not evaluate whether the aggressive treatment strategies improved or harmed patients' quality of life, nor did it assess cost-effectiveness. Recovery from aggressive liver surgery can significantly impact quality of life.

Perhaps most notably, the authors note that at the time of writing, there are currently no registered clinical trials exploring surgical resection of BCLM. This means the evidence base — while suggestive — has not yet been validated through the gold standard of randomized prospective research.

Recommendations: What Patients Should Consider

Based on this study and the existing medical literature, here are key takeaways for patients and their families:

1. Discuss surgical options with your multidisciplinary team. The authors conclude that liver resection "may be considered at multidisciplinary meetings" for patients with breast cancer liver metastases. If your care is being managed by a tumor board or multidisciplinary team, ask whether liver resection has been discussed as a potential option in your case.
2. Understand your candidacy. The best candidates for liver resection appear to be those with a single or few liver lesions, no cancer spread beyond the liver, a long disease-free interval (more than 24 months) since the original breast cancer diagnosis, negative lymph nodes at the original breast surgery, and a tumor biology that is not triple-negative. If you fall into these categories, surgery may offer a meaningful survival benefit.
3. Expect a combination approach. In the studies analyzed, patients who underwent surgery typically also received systemic therapies — chemotherapy, hormonal therapy, or HER2-targeted treatments. Liver resection is not presented as a replacement for these treatments but as an addition to them, and preoperative ("neoadjuvant") chemotherapy may be used to control disease before surgery.
4. Ask about the goal of surgery. The authors use the phrase "potentially curative" — this is carefully worded. For a minority of patients with disease truly confined to the liver, surgery may achieve complete removal of all visible cancer. For others, surgery may extend life without achieving cure. Make sure you understand what the realistic goal is in your specific situation.
5. Weigh quality-of-life considerations. Liver resection is a major operation with a significant recovery period. While this study did not formally measure quality of life, the authors caution that recovery from aggressive treatment can impact patients' well-being. Discuss the expected recovery time and potential complications with your surgical team.
6. Stay informed about ongoing research. Since no randomized controlled trials of liver resection for BCLM are currently registered, this is an evolving field. New evidence could emerge that changes recommendations. Consider asking your oncologist about any active clinical trials that might be relevant to your situation.
7. Individualize the decision. The authors emphasize "judicious patient selection is crucial." Every patient's cancer is different — different hormone receptor status, different HER2 status, different patterns of spread, different responses to prior treatments. What works for one patient may not be right for another. The decision about liver resection should be a personalized one, made in collaboration with your full medical team.

The bottom line: This meta-analysis provides the strongest evidence to date that liver resection may improve survival for carefully selected women with breast cancer liver metastases. The 31% reduction in mortality risk (HR: 0.69) and the dramatic differences in 5-year survival (46.0% vs. 24.7%) are compelling. But these results must be weighed alongside the study's limitations — most importantly, the lack of randomized data and the real possibility that selection bias influenced the outcomes. For now, liver resection should be considered a promising option for well-chosen patients, not a guaranteed solution for everyone.

Frequently Asked Questions

What is the main finding of this review?

In a meta-analysis of 1,732 patients from 9 studies, surgically removing breast cancer liver metastases was associated with a 31% lower risk of dying during follow-up compared with no surgery. Five-year survival was 46.0% with surgery versus 24.7% without. However, no randomized trials were included, so results should be interpreted cautiously.

Which patients might be considered for liver resection?

Patients most likely to benefit appear to be those with a single or few liver lesions, no cancer spread beyond the liver, a gap of more than 24 months since the original breast cancer diagnosis, negative lymph nodes at the original breast surgery, and tumor biology that is not triple-negative. These factors should be discussed with a multidisciplinary team.

Is liver resection potentially curative for breast cancer liver metastases?

The authors use the carefully worded term "potentially curative" for a minority of patients whose disease is truly confined to the liver. For others, surgery may extend life without achieving cure. Because no randomized controlled trials exist, liver resection is not currently a standard option for all patients with this condition.

What are the main limitations of this study?

None of the 9 included studies were randomized, so patients who had surgery may have been healthier or had less extensive disease. Studies varied in treatments and surgical techniques, and there was high statistical inconsistency at some time points. Quality of life and cost-effectiveness were not assessed.

What treatments were combined with liver resection?

In the reviewed studies, patients who had liver resection typically also received systemic therapies such as chemotherapy, hormonal therapy, or HER2-targeted treatments. Preoperative (neoadjuvant) chemotherapy might be used to control disease before surgery. Liver resection was an addition to these treatments, not a replacement for them.

I have breast cancer that has spread to my liver — should I get a second opinion before deciding whether to have liver surgery?

Yes. Liver resection for breast cancer liver metastases has been associated with improved survival: in a meta-analysis of 1,732 patients, surgery patients had a 31% lower risk of death, and 5-year survival was 46.0% versus 24.7% without surgery. However, these results come from non-randomized studies, so selection bias is possible. Candidacy is highly individual, and factors like number of liver lesions, extrahepatic disease, disease-free interval, and tumor biology matter. A second opinion can help you weigh whether surgery is appropriate for your specific situation and what alternatives exist. Diagnostic Detectives Network provides independent expert second opinions.

Source Information

Original Article Title: The impact of liver resection on survival for patients with metastatic breast cancer

Authors: Gavin G. Calpin, Matthew G. Davey, Pádraig Calpin, Ferdia Browne, Aoife J. Lowery, Michael J. Kerin

Journal: The Surgeon (2023), Volume 21, Pages 242–249. Published by Elsevier Ltd on behalf of the Royal College of Surgeons of Edinburgh and Royal College of Surgeons in Ireland.

Publication Details: Received May 26, 2022; accepted October 13, 2022; available online November 1, 2022. DOI: https://doi.org/10.1016/j.surge.2022.10.001

Funding: This research received no external funding. All authors declared no conflicts of interest.

Note: This patient-friendly article is based on peer-reviewed research. It is intended for informational purposes only and is not a substitute for professional medical advice. Patients should always consult their healthcare team about their individual diagnosis and treatment options.