HER2 significance and treatment outcomes after radiotherapy for brain metastases in breast cancer patients

The relationship between brain metastasis and HER2 expression status in gastric cancer

BACKGROUND

Brain metastasis (BM) in gastric cancer (GC) is underestimated, and human epidermal growth factor receptor 2 (HER2) overexpression is a durable poor prognostic factor. We explored the relationship between the two and made a survival analysis.

METHODS

HER2 expression and BM status were collected from GC patients who were diagnosed between December 2009 and May 2021. We collected GC patients diagnosed between 2010 and 2016 from the SEER database. The primary endpoint was survival from the diagnosis of BM. Multivariable logistic regression was used to determine potential risk factors of BM at diagnosis in SEER database. Survival analysis was performed using the Kaplan-Meier method.

RESULT

There were 513 HER2-positive GC patients, including 16 (3.1%) with BM. Among 38 brain metastasis GC patients we collected, 16 (42.1%) patients were HER2 positive. We collected 34,199 GC patients from the SEER database and there were 260 (0.76%) patients with BM at diagnosis. GC patients that are male, white, of younger age, with primary lesions located in the proximal stomach or with distant lymph nodes, liver, bone, or lung metastasis are more likely to develop BM. The median overall survival time from diagnosis of BM was 12.73 months, and the survival time from brain metastasis of HER2-positive patients was numerically shorter, though the difference was not significant (5.30 months vs.16.13 months, P = 0.28.) CONCLUSION: The incidence of BM in patients with HER2-positive gastric cancer is 4.08 times higher than that in general patients. The median overall survival time from BM is shorter for HER2-positive patients.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Role of Whole Brain Radiation Therapy in Adults With Newly Diagnosed Metastatic Brain Tumors

TARGET POPULATION

Adult patients (older than 18 yr of age) with newly diagnosed brain metastases.

QUESTION

If whole brain radiation therapy (WBRT) is used, is there an optimal dose/fractionation schedule?

RECOMMENDATIONS

Level 1:  A standard WBRT dose/fractionation schedule (ie, 30 Gy in 10 fractions or a biological equivalent dose [BED] of 39 Gy10) is recommended as altered dose/fractionation schedules do not result in significant differences in median survival or local control. Level 3: Due to concerns regarding neurocognitive effects, higher dose per fraction schedules (such as 20 Gy in 5 fractions) are recommended only for patients with poor performance status or short predicted survival. Level 3: WBRT can be recommended to improve progression-free survival for patients with more than 4 brain metastases.

QUESTION

What impact does tumor histopathology or molecular status have on the decision to use WBRT, the dose fractionation scheme to be utilized, and its outcomes?

RECOMMENDATIONS

There is insufficient evidence to support the choice of any particular dose/fractionation regimen based on histopathology. Molecular status may have an impact on the decision to delay WBRT in subgroups of patients, but there is not sufficient data to make a more definitive recommendation.

QUESTION

Separate from survival outcomes, what are the neurocognitive consequences of WBRT, and what steps can be taken to minimize them?

RECOMMENDATIONS

Level 2: Due to neurocognitive toxicity, local therapy (surgery or SRS) without WBRT is recommended for patients with ≤4 brain metastases amenable to local therapy in terms of size and location. Level 2:  Given the association of neurocognitive toxicity with increasing total dose and dose per fraction of WBRT, WBRT doses exceeding 30 Gy given in 10 fractions, or similar biologically equivalent doses, are not recommended, except in patients with poor performance status or short predicted survival. Level 2: If prophylactic cranial irradiation (PCI) is given to prevent brain metastases for small cell lung cancer, the recommended WBRT dose/fractionation regimen is 25 Gy in 10 fractions, and because this can be associated with neurocognitive decline, patients should be told of this risk at the same time they are counseled about the possible survival benefits. Level 3: Patients having WBRT (given for either existing brain metastases or as PCI) should be offered 6 mo of memantine to potentially delay, lessen, or prevent the associated neurocognitive toxicity.

QUESTION

Does the addition of WBRT after surgical resection or radiosurgery improve progression-free or overall survival outcomes when compared to surgical resection or radiosurgery alone?

RECOMMENDATIONS

Level 2: WBRT is not recommended in WHO performance status 0 to 2 patients with up to 4 brain metastases because, compared to surgical resection or radiosurgery alone, the addition of WBRT improves intracranial progression-free survival but not overall survival. Level 2: In WHO performance status 0 to 2 patients with up to 4 brain metastases where the goal is minimizing neurocognitive toxicity, as opposed to maximizing progression-free survival and overall survival, local therapy (surgery or radiosurgery) without WBRT is recommended. Level 3: Compared to surgical resection or radiosurgery alone, the addition of WBRT is not recommended for patients with more than 4 brain metastases unless the metastases' volume exceeds 7 cc, or there are more than 15 metastases, or the size or location of the metastases are not amenable to surgical resection or radiosurgery.The full guideline can be found at: https://www.cns.org/guidelines/guidelines-treatment-adults-metastatic-brain-tumors/chapter_3.

The breast graded prognostic assessment is associated with the survival outcomes in breast cancer patients receiving whole brain re-irradiation

INTRODUCTION

Whole brain (WB) re-irradiation for breast cancer patients with progressive brain metastasis after first-course WB radiotherapy (WBRT) is controversial. In this study, we sought to investigate the association between the molecular sub-classifications and breast-specific Graded Prognostic Assessment (GPA, which includes the Karnofsky performance status, molecular subtypes, and age as its indices) and the outcomes of breast cancer patients who received WB re-irradiation.

METHODS

Twenty-three breast cancer patients who received WB re-irradiation for relapsed and progressive intracranial lesions after first-course WBRT between 2004 and 2016 were retrospectively reviewed. Patients were divided according to the 4 molecular subtypes of luminal A/B (hormone receptor [HR]+/human epidermal growth factor receptor 2 [HER2]-), luminal HER2 (HR+/HER2+), HER2 (HR-/HER2+), and triple negative (HR-/HER2-). The clinical and radiological responses and survival rates after WB re-irradiation were analyzed.

RESULTS

At 1 month after WB re-irradiation, 13 of 23 patients (56.5%) exhibited disappearance or alleviation of neurological symptoms. The median survival time after WB re-irradiation was 2.93 months (95% confidence interval [CI], 1.79-4.08). After WB re-irradiation, patients with HER2-negative tumors had poorer median survival times than those with HER2-positive tumors (2.23 vs. 3.0 months, respectively; p = 0.022). Furthermore, patients with high breast GPA scores (2.5-4.0, n = 11) had longer median survivals than those with low-scores (0-2.0, n = 12) after WB re-irradiation (4.37 vs. 1.57 months, respectively; p < 0.005).

CONCLUSIONS

WB re-irradiation may be a feasible treatment option for certain breast cancer patients who develop brain metastatic lesions after first-course WBRT when these lesions are ineligible for radiosurgery or surgery.

Brain Metastases in Breast Cancer: Analysis of the Role of HER2 Status and Treatment in the Outcome of 94 Patients

Aims and background

We investigated the impact of human epidermal growth factor receptor 2 (HER2) and prognostic factors in the outcome of patients with breast cancer that developed brain metastases.

Methods

The data from 94 patients who received multidisciplinary therapy from 2001 to 2007 were retrospectively reviewed. Patients were assigned according to their HER2 status, and overall survival and time to brain metastases recurrence/progression were evaluated. The prognostic value of age, presence of extracerebral metastases, recursive partitioning analysis class, hormone therapy, systemic therapy and trastuzumab was assessed.

Results

The median overall survival and time to brain disease progression were 7.1 and 6.5 months, respectively. HER2 positivity (P = 0.006), treatment with trastuzumab (P = 0.025), chemotherapy (P = 0.011) and recursive partitioning analysis class I-II (P <0.001) were associated with prolonged survival on univariate analysis. On multivariate analysis, only recursive partitioning analysis class I-II (P <0.001) and triple-negative disease (P = 0.04) remained significant for overall survival, whereas time to brain metastases progression was only associated with recursive partitioning analysis class I-II (P = 0.001). The time from the diagnosis of primary disease to brain metastasis was slightly shorter in the HER2+ patients than in HER2– patients (36 vs 39 months). Intensified local treatment of brain metastasis incorporating whole-brain radiotherapy and/or radiosurgery and neurosurgery did not affect survival. Patients with triple-negative disease presented a significantly lower survival than the rest of the cohort (4 vs 8 months; P = 0.012).

Conclusions

Recursive partitioning analysis class I-II was found to be the strongest independent predictive factor. Treatment with trastuzumab in HER2+ patients appeared to improve overall survival, probably due to the better control of systemic metastatic disease, but did not maintain significance in multivariate analysis. The dismal prognosis of patients with triple-negative breast cancer highlights the need to develop novel therapies to improve the poor survival.

Breast cancer brain metastases - A 12 year review of treatment outcomes

BACKGROUND

Breast cancer (BC) is the 2nd commonest cause of brain metastases (BM). This retrospective review investigates the applicability of prognostic scores and highlights different outcomes for patients with HER2 positive compared to triple negative (TN) subtypes.

METHODS

Two hundred and seventy four patients received whole brain radiotherapy for BC BM (01/2000-12/2011). The primary objective was to determine factors influencing overall survival (OS). All information relevant to primary BC, disease recurrence, treatment, outcome and cause of death (either neurological (NP) or systemic progression (SP)) were collected. Univariate (UV) and multivariate (MV) Cox regression analysis were used.

RESULTS

One hundred and forty four patients (53%) were ER positive, 104 (38%) HER2 positive and 57 (21%) TN. Median age at BM was 53 (27-81) years and median OS from BM diagnosis 7.3 (5.7-8.9) months. On MV analysis, Her2 status, RPA score, surgery, stereotactic radiotherapy, and absence of TN disease were independent prognostic factor for OS. NP was the cause of death in 69.2% of HER2 positive patients and 17.3% had SP. Of the TN patients, 29.8% had NP and 54.4% SP (p < 0.001).

CONCLUSION

A consistent OS advantage is noted for HER2 positive BM cases and inclusion of BC subtype in the breast GPA score should improve the prognostic factors' sensitivity. The unique presentations, response to treatment and causes of death for HER2 positive patients means more aggressive focal therapy should be considered and studied in the context of clinical trials. For TN BM patients with poor performance status, best supportive care may be appropriate.

Prognostic significance of pathological complete response following neoadjuvant chemotherapy for operable breast cancer

The aim of the present retrospective study was to ascertain the significance of pathological complete response (pCR) on overall survival (OS) and disease-free survival (DFS) in each disease subtype of operable breast cancer. Using a single-institution database, 90 patients were identified, who received neoadjuvant chemotherapy (NAC) for operable breast cancer and were eligible for the analysis. In total, 10 patients (11.1%) had succumbed to their diseases and 20 (22.2%) had succumbed to their diseases or exhibited recurrences. The OS of patients with triple-negative (TN) tumors was significantly lower than that of patients with other disease subtypes (P=0.016). The DFS of patients with luminal tumors was higher than that of patients with other subtypes. Survival was improved with pCR following NAC (P=0.044). Across all subtypes, patients who achieved pCR exhibited a higher DFS than patients who did not, but not significantly. pCR only improved OS and DFS in the TN disease subtype (P=0.022 and P=0.048, respectively). pCR following NAC may have prognostic value in TN breast cancer.

Gamma knife radiosurgery for brain metastases from breast cancer

Objective

The authors conducted a retrospective cohort study to determine prognostic factors and treatment outcomes of brain metastases (BM) from breast cancer (BC) after Gamma Knife radiosurgery (GKS).

Methods

Pathologic and clinical features, and outcomes were analyzed in a cohort of 62 patients with BM from BC treated by GKS. The Kaplan-Meier method, the log-rank test, and Cox's proportional hazards model were used to assess prognostic factors.

Results

Median survival after GKS was 73.0 weeks (95% confidence interval, 46.0-100.1). HER2+ [hazard ratio (HR) 0.441; p=0.045], Karnofsky performance scale (KPS) ≥70 (RR 0.416; p=0.050) and systemic chemotherapy after GKS (RR 0.282; p=0.001) were found to be a favorable prognostic factor of overall survival. Actuarial local control (LC) rate were 89.5±4.5% and 70.5±6.9% at 6 and 12 months after GKS, respectively. No prognostic factors were found to affect LC rate. Uni- and multivariate analysis revealed that the distant control (DC) rate was higher in patients with; a small number (≤3) of metastasis (HR 0.300; p=0.045), no known extracranial metastasis (p=0.013, log-rank test), or the HER2+ subtype (HR 0.267; p=0.027). Additional whole brain radiation therapy and metastasis volume were not found to be significantly associated with LC, DC, or overall survival.

Conclusion

The treatment outcomes of patients with newly diagnosed BM from BC treated with GKS could be affected primarily by intrinsic subtype, KPS, and systemic chemotherapy. Therapeutic strategy and prognosis scoring system should be individualized based on considerations of intrinsic subtype in addition to traditionally known parameters related to stereotactic radiosurgery.

A systematic review of trastuzumab and lapatinib in the treatment of women with brain metastases from HER2-positive breast cancer

Patients with HER2-positive breast cancer are living still longer and increasingly experiencing brain metastases. Current HER2-targeted therapies have limited potential to cross the blood-brain-barrier. We performed a systematic review to investigate data on HER2-targeting therapies in the treatment of brain metastases in breast cancer. We searched PUBMED for all human studies published 1998-2012 using the following search terms: breast neoplasm/cancer, human epidermal growth factor receptor 2/HER2, ErbB2, trastuzumab, lapatinib, brain/cerebral neoplasm/metastases and blood-brain barrier. We identified few and mostly small clinical studies. Study designs were very heterogeneous making comparisons on endpoints difficult. Overall survival for patients treated with trastuzumab varied from 8 to 25 months and 5.5 to 11 months for patients receiving lapatinib. The majority of studies were retrospective thus possibly biasing data. Only three studies were identified comparing trastuzumab to lapatinib. Conclusively, no solid data exist on how to treat patients with HER2-positive disease and brain metastases. Although continuous HER2-blockade is recommended by international consensus guidelines, it is still not evident which HER2-targeting agent should be preferred when brain metastases occur. The choice of chemotherapy to accompany the blockade is not obvious and we do not know if dual is better than single blockade. Further clinical trials are urgently needed.

Brain metastases in Asian HER2-positive breast cancer patients: anti-HER2 treatments and their impact on survival

BACKGROUND

In Asia, large-scale studies on anti-HER2 treatment in HER2-positive breast cancer patients with brain metastases are limited. We studied the treatment patterns of these patients in Asia to evaluate the impact of anti-HER2 treatment on the time to occurrence of brain metastases (TTBM) and survival after brain metastasis (BM).

METHODS

A retrospective study of HER2-positive breast cancer patients diagnosed with BM between January 2006 and December 2008 in six Asian countries was conducted. Demographics, tumour characteristics, treatment details, and events dates were collected from medical records.

RESULTS

Data from 280 patients were analysed. Before BM, 63% received anti-HER2 treatment. These patients had significantly longer TTBM than those without anti-HER2 treatment (median 33 vs 19 months; P<0.002). After BM, 93% received radiotherapy, 57% received chemotherapy, and 41% received anti-HER2 treatment (trastuzumab and/or lapatinib). Use of both anti-HER2 agents, primarily sequentially, after BM demonstrated the longest survival after BM and was associated with a significant survival benefit over no anti-HER2 treatment (median 26 vs 6 months; hazard ratio 0.37; 95% CI 0.19-0.72).

CONCLUSION

Anti-HER2 treatment before BM was associated with longer TTBM. Anti-HER2 treatment after BM was associated with a survival benefit, especially when both trastuzumab and lapatinib were utilised.

Management of patients with brain metastases receiving trastuzumab treatment for metastatic breast cancer

BACKGROUND

With the more effective control of visceral metastases in patients with metastatic breast cancer (MBC), an increasing number of patients face brain metastases (BM). The aim of this retrospective analysis was to investigate the incidence and factors affecting the prognosis of patients with BM under trastuzumab treatment for MBC.

PATIENTS AND METHODS

A total of 75 HER2positive patients treated with trastuzumab for MBC were included. RESULTS are discussed in the context of the current literature.

RESULTS

Patients who developed BM (n = 29) had longer median progression-free survival (PFS) during first-line chemotherapy and longer overall survival (OS) after diagnosis of MBC than 46 patients without BM (PFS: 27 vs. 14 months, p = 0.039; OS: 46 vs. 18 months, p = 0.067). Median survival of patients with continuation of trastuzumab after diagnosis of BM was longer than survival of patients with discontinuation of trastuzumab treatment after BM (18 vs. 3 months, p = 0.006). Survival of patients who were treated with surgery and radiotherapy for BM was better compared with radiotherapy alone (9 vs. 5 months, p = not significant) or best supportive care (9 vs. 2 months, p = 0.049).

CONCLUSIONS

Continuation of trastuzumab treatment as well as resection of BM seem to give further benefit in the treatment of patients with HER2-overexpressing MBC.

Clinicopathological features of breast cancers predict the development of leptomeningeal metastases: a case-control study

The incidence of leptomeningeal metastases (LM) in patients with breast cancer (BC) is increasing as a result of increased screening and improved patient survival. However, the median survival time after diagnosis of LM is between 5 weeks (without any treatment) and 5 months (for aggressively treated patients). In an attempt to identify clinicopathological risk factors for LM, we carried out a case-control study of 100 women with BC. Fifty patients with BC and LM were enrolled and an additional 50 patients with BC and no CNS metastases including leptomeningeal spread were selected as controls. Patients who had developed LM were selected between December 2006 and August 2008. The control group was matched for: age at diagnosis, year of diagnosis, and initiation of chemotherapy at BC diagnosis. The ILC type (P = 0.03), ER-negative (P = 0.01) and PR-negative status (P = 0.03), and initial M+ status at BC diagnosis (P = 0.008) tended to be more frequent in LM patients. These characteristics should lead to early appropriate assessments being performed in this targeted population when a neurological complaint appears, in order to detect LM as soon as possible.

Radiation therapy for brain metastases in breast cancer patients

Most randomized comparison trials (RCTs) investigating treatments for brain metastases (BM) have included BM from any origin; as a result, more than half (52.4-77.0%) of the BM in these trials originated from the lungs (mostly non-small-cell lung cancer, NSCLC), with the breasts being the origin in only 6.8-19.0% of cases. In addition, patients with poor systemic status (KPS < 70) were not included in these trials. Hence, before we can apply RCT-based information to the daily clinical treatment of BM from breast cancers, it will be crucial to differentiate the characteristics of BM originating from NSCLC and BM originating from breast cancer. Although stereotactic radiosurgery (SRS) is widely used in Japan, level-1 evidence suggests that the benefit of using SRS in addition to whole-brain radiation therapy (WBRT) has been proven only for patients with a single BM. Treatment with SRS alone, which is widely used in Japan, seems attractive because it could avoid the risk of long-term adverse effects of WBRT. However, level-1 evidence suggests that the omission of WBRT results in a high frequency of brain tumor recurrence (BTR). In an RCT between SRS-alone and SRS + WBRT conducted in Japan, we found that patients who had a single BM and no extracranial metastases had a low risk of developing BTR after initial brain management (low-risk group) compared with those who had 2 or more BM and extracranial metastases (high-risk group). In order to meet the criteria of "low-risk" BTR, patients also should have good systemic status (KPS ≧ 70). Epidemiologic data suggest that the prognosis is twice as likely to be poor in patients with BM from breast cancer (RPA III = KPS < 70) than in patients with BM from NSCLC (40 vs. 20%); in addition, the probability of brain-only metastases in patients with breast cancer is less than half that in patients with NSCLC (20-25 vs. 60-75%). Considering these findings, we should be aware that most patients with BM from breast cancer are not good candidates for SRS alone, and, therefore, the role of WBRT is still important in the era of modern radiation techniques.

Diagnostic tools for neoplastic meningitis: detecting disease, identifying patient risk, and determining benefit of treatment

Three methods are routinely used to diagnose neoplastic meningitis (NM): clinical signs and symptoms, cerebrospinal fluid (CSF) cytology, and magnetic resonance imaging (MRI) of the brain and spine. Clinical manifestations are often subtle or may be ascribed to other cancer complications, eg, treatment-related disorders or brain parenchymal metastases. CSF cytology has a high specificity (>95%), but its sensitivity is generally less than 50%. MRI sensitivity and specificity vary with the type of primary cancer; overall, MRI findings consistent with leptomeningeal disease are detected in fewer than 50% of NM patients. While most clinicians evaluate CSF cytology along with MRI and the clinical examination, underdiagnosis is a major problem, since many patients are both cytologically and radiographically negative. Failure to consider NM in the differential diagnosis magnifies the problem of underdiagnosis. CSF flow cytometry is particularly promising for evaluating NM from hematologic cancers, with a diagnostic sensitivity many fold greater than conventional cytology. Research has focused on identifying biochemical markers of tumor cells in the CSF. For example, molecules involved in CNS penetration (eg, matrix metalloproteinases and cathepsins), tumor cell tropism (eg, chemokines CXCL8 and CCL18), and angiogenesis (eg, vascular endothelial growth factor) are elevated in the CSF of patients with NM. Evidence that some tumor types are more likely to infiltrate the CNS also has stimulated research into primary tumor markers predictive of CNS metastases. At present, there is no tumor marker or patient characteristic that reliably predicts the development of NM, and diagnosis still relies on suggestive signs and symptoms, positive CSF cytology, or a consistent MRI-all late manifestations of NM. Until techniques capable of detecting NM early are developed, increased awareness of the disease and standardized evaluation are likely to have the greatest impact on improving diagnosis and implementing earlier treatment.

The HER-2 receptor and breast cancer: ten years of targeted anti-HER-2 therapy and personalized medicine

The human epidermal growth factor receptor (HER-2) oncogene encodes a transmembrane tyrosine kinase receptor that has evolved as a major classifier of invasive breast cancer and target of therapy for the disease. The validation of the general prognostic significance of HER-2 gene amplification and protein overexpression in the absence of anti-HER-2 targeted therapy is discussed in a study of 107 published studies involving 39,730 patients, which produced an overall HER-2-positive rate of 22.2% and a mean relative risk for overall survival (OS) of 2.74. The issue of HER-2 status in primary versus metastatic breast cancer is considered along with a section on the features of metastatic HER-2-positive disease. The major marketed slide-based HER-2 testing approaches, immunohistochemistry, fluorescence in situ hybridization, and chromogenic in situ hybridization, are presented and contrasted in detail against the background of the published American Society of Clinical Oncology-College of American Pathologists guidelines for HER-2 testing. Testing issues, such as the impact of chromosome 17 polysomy and local versus central HER-2 testing, are also discussed. Emerging novel HER-2 testing techniques, including mRNA-based testing by real-time polymerase chain reaction and DNA microarray methods, HER-2 receptor dimerization, phosphorylated HER-2 receptors, and HER-2 status in circulating tumor cells, are also considered. A series of biomarkers potentially associated with resistance to trastuzumab is discussed with emphasis on the phosphatase and tensin homologue deleted on chromosome ten/Akt and insulin-like growth factor receptor pathways. The efficacy results for the more recently approved small molecule HER-1/HER-2 kinase inhibitor lapatinib are also presented along with a more limited review of markers of resistance for this agent. Additional topics in this section include combinations of both anti-HER-2 targeted therapies together as well as with novel agents including bevacizumab, everolimus, and tenespimycin. A series of novel HER-2-targeting agents is also presented, including pertuzumab, ertumaxomab, HER-2 vaccines, and recently discovered tyrosine kinase inhibitors. Biomarkers predictive of HER-2 targeted therapy toxicity are included, and the review concludes with a consideration of HER-2 status in the prediction of response to non-HER-2 targeted treatments including hormonal therapy, anthracyclines, and taxanes.