Tumor-infiltrating lymphocytes in HER2-positive breast cancer treated with neoadjuvant chemotherapy and dual HER2-blockade

Tumor-infiltrating lymphocytes (TILs) have been associated with outcomes in HER2-positive breast cancer patients treated with neoadjuvant chemotherapy and trastuzumab. However, it remains unclear if TILs could be a prognostic and/or predictive biomarker in the context of dual HER2-targeting treatment. In this study, we evaluated the association between TILs and pathological response (pCR) and invasive-disease free survival (IDFS) in 389 patients with stage II-III HER2 positive breast cancer who received neoadjuvant anthracycline-containing or anthracycline-free chemotherapy combined with trastuzumab and pertuzumab in the TRAIN-2 trial. Although no significant association was seen between TILs and pCR, patients with TIL scores ≥60% demonstrated an excellent 3-year IDFS of 100% (95% CI 100-100), regardless of hormone receptor status, nodal stage and attainment of pCR. Additionally, in patients with hormone receptor positive disease, TILs as a continuous variable showed a trend to a positive association with pCR (adjusted Odds Ratio per 10% increase in TILs 1.15, 95% CI 0.99-1.34, p = 0.070) and IDFS (adjusted Hazard Ratio per 10% increase in TILs 0.71, 95% CI 0.50-1.01, p = 0.058). We found no interactions between TILs and anthracycline treatment. Our results suggest that high TIL scores might be able to identify stage II-III HER2-positive breast cancer patients with a favorable prognosis.

Gene expression profiles in clinically T1-2N0 ER+HER2- breast cancer patients treated with breast-conserving therapy: their added value in case sentinel lymph node biopsy is not performed

PURPOSE

Omitting sentinel lymph node biopsy (SLNB) in breast cancer treatment results in patients with unknown positive nodal status and potential risk for systemic undertreatment. This study aimed to investigate whether gene expression profiles (GEPs) can lower this risk in cT1-2N0 ER+ HER2- breast cancer patients treated with BCT.

METHODS

Patients were included if diagnosed between 2011 and 2017 with cT1-2N0 ER+ HER2- breast cancer, treated with BCT and SLNB, and in whom GEP was applied. Adjuvant chemotherapy recommendations based on clinical risk status (Dutch breast cancer guideline of 2020 versus PREDICT v2.1) with and without knowledge on SLNB outcome were compared to GEP outcome. We examined missing adjuvant chemotherapy indications, and the number of GEPs needed to identify one patient at risk for systemic undertreatment.

RESULTS

Of 3585 patients, 2863 (79.9%) had pN0 and 722 (20.1%) pN + disease. Chemotherapy was recommended in 1354 (37.8% guideline-2020) and 1888 patients (52.7% PREDICT). Eliminating SLNB outcome (n = 722) resulted in omission of chemotherapy recommendation in 475 (35.1% guideline-2020) and 412 patients (21.8% PREDICT). GEP revealed genomic high risk in 126 (26.5% guideline-2020) and 82 patients (19.9% PREDICT) in case of omitted chemotherapy recommendation in the absence of SLNB. Extrapolated to the whole group, this concerns 3.5% and 2.3%, respectively, resulting in the need for 28-44 GEPs to identify one patient at risk for systemic undertreatment.

CONCLUSION

If no SLNB is performed, clinical risk status according to the guideline of 2020 and PREDICT predicts a very low risk for systemic undertreatment. The number of GEPs needed to identify one patient at risk for undertreatment does not justify its standard use.

Updated overall survival from the MONALEESA-3 trial in postmenopausal women with HR+/HER2- advanced breast cancer receiving first-line ribociclib plus fulvestrant

BACKGROUND

The phase III MONALEESA-3 trial included first- (1L) and second-line (2L) patients and demonstrated a significant overall survival (OS) benefit for ribociclib + fulvestrant in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer (ABC) in the final protocol-specified and exploratory (longer follow-up) OS analyses. At the time of these analyses, the full OS benefit of 1L ribociclib was not completely characterized because the median OS (mOS) was not reached. As CDK4/6 inhibitor (CDK4/6i) + endocrine therapy (ET) is now a preferred option for 1L HR+/HER2- ABC, we report an exploratory analysis (median follow-up, 70.8 months; 14.5 months longer than the prior analysis) to fully elucidate the OS benefit in the MONALEESA-3 1L population.

METHODS

Postmenopausal patients with HR+/HER2- ABC were randomized 2:1 to 1L/2L fulvestrant + ribociclib or placebo. OS in 1L patients (de novo disease or relapse > 12 months from completion of [neo]adjuvant ET) was assessed by Cox proportional hazards model and Kaplan-Meier methods. Progression-free survival 2 (PFS2) and chemotherapy-free survival (CFS) were analyzed. MONALEESA-3 is registered with ClinicalTrials.gov (NCT02422615).

RESULTS

At data cutoff (January 12, 2022; median follow-up time, 70.8 months), mOS was 67.6 versus 51.8 months with 1L ribociclib versus placebo (hazard ratio (HR) 0.67; 95% CI 0.50-0.90); 16.5% and 8.6% of ribociclib and placebo patients, respectively, were still receiving treatment. PFS2 (HR 0.64) and CFS (HR 0.62) favored ribociclib versus placebo. Among those who discontinued treatment, 16.7% and 35.0% on ribociclib or placebo, respectively, received a subsequent CDK4/6i. No new safety signals were observed.

CONCLUSIONS

This analysis of MONALEESA-3 reports the longest mOS thus far (67.6 months) for 1L patients in a phase III ABC trial. These results in a 1L population show that the OS benefit of ribociclib was maintained through extended follow-up, further supporting its use in HR+/HER2- ABC.

Unleashing NK- and CD8 T cells by combining monalizumab and trastuzumab for metastatic HER2-positive breast cancer: Results of the MIMOSA trial

The large majority of patients with HER2-positive metastatic breast cancer (MBC) will eventually develop resistance to anti-HER2 therapy and die of this disease. Despite, relatively high levels of stromal tumor infiltrating lymphocytes (sTILs), PD1-blockade has only shown modest responses. Monalizumab targets the inhibitory immune checkpoint NKG2A, thereby unleashing NK- and CD8 T cells. We hypothesized that monalizumab synergizes with trastuzumab by promoting antibody-dependent cell-mediated cytotoxicity. In the phase II MIMOSA-trial, HER2-positive MBC patients were treated with trastuzumab and 750 mg monalizumab every two weeks. Following a Simon's two-stage design, 11 patients were included in stage I of the trial. Treatment was well tolerated with no dose-limiting toxicities. No objective responses were observed. Therefore, the MIMOSA-trial did not meet its primary endpoint. In summary, despite the strong preclinical rationale, the novel combination of monalizumab and trastuzumab does not induce objective responses in heavily pre-treated HER2-positive MBC patients.

BluePrint molecular subtypes predict response to neoadjuvant pertuzumab in HER2-positive breast cancer

BACKGROUND

The introduction of pertuzumab has greatly improved pathological complete response (pCR) rates in HER2-positive breast cancer, yet effects on long-term survival have been limited and it is uncertain which patients derive most benefit. In this study, we determine the prognostic value of BluePrint subtyping in HER2-positive breast cancer. Additionally, we evaluate its use as a biomarker for predicting response to trastuzumab-containing neoadjuvant chemotherapy with or without pertuzumab.

METHODS

From a cohort of patients with stage II-III HER2-positive breast cancer who were treated with neoadjuvant chemotherapy and trastuzumab with or without pertuzumab, 836 patients were selected for microarray gene expression analysis, followed by readout of BluePrint standard (HER2, Basal and Luminal) and dual subtypes (HER2-single, Basal-single, Luminal-single, HER2-Basal, Luminal-HER2, Luminal-HER2-Basal). The associations between subtypes and pathological complete response (pCR), overall survival (OS) and breast cancer-specific survival (BCSS) were assessed, and pertuzumab benefit was evaluated within the BluePrint subgroups.

RESULTS

BluePrint results were available for 719 patients. In patients with HER2-type tumors, the pCR rate was 71.9% in patients who received pertuzumab versus 43.5% in patients who did not (adjusted Odds Ratio 3.43, 95% CI 2.36-4.96). Additionally, a significantly decreased hazard was observed for both OS (adjusted hazard ratio [aHR] 0.45, 95% CI 0.25-0.80) and BCSS (aHR 0.46, 95% CI 0.24-0.86) with pertuzumab treatment. Findings were similar in the HER2-single subgroup. No significant benefit of pertuzumab was seen in other subtypes.

CONCLUSIONS

In patients with HER2-type or HER2-single-type tumors, pertuzumab significantly improved the pCR rate and decreased the risk of breast cancer mortality, which was not observed in other subtypes. BluePrint subtyping may be valuable in future studies to identify patients that are likely to be highly sensitive to HER2-targeting agents.

Effect of physical exercise on the hippocampus and global grey matter volume in breast cancer patients: A randomized controlled trial (PAM study)

BACKGROUND

Physical exercise in cancer patients is a promising intervention to improve cognition and increase brain volume, including hippocampal volume. We investigated whether a 6-month exercise intervention primarily impacts total hippocampal volume and additionally hippocampal subfield volumes, cortical thickness and grey matter volume in previously physically inactive breast cancer patients. Furthermore, we evaluated associations with verbal memory.

METHODS

Chemotherapy-exposed breast cancer patients (stage I-III, 2-4 years post diagnosis) with cognitive problems were included and randomized in an exercise intervention (n = 70, age = 52.5 ± 9.0 years) or control group (n = 72, age = 53.2 ± 8.6 years). The intervention consisted of 2x1 hours/week of supervised aerobic and strength training and 2x1 hours/week Nordic or power walking. At baseline and at 6-month follow-up, volumetric brain measures were derived from 3D T1-weighted 3T magnetic resonance imaging scans, including hippocampal (subfield) volume (FreeSurfer), cortical thickness (CAT12), and grey matter volume (voxel-based morphometry CAT12). Physical fitness was measured with a cardiopulmonary exercise test. Memory functioning was measured with the Hopkins Verbal Learning Test-Revised (HVLT-R total recall) and Wordlist Learning of an online cognitive test battery, the Amsterdam Cognition Scan (ACS Wordlist Learning). An explorative analysis was conducted in highly fatigued patients (score of ≥ 39 on the symptom scale 'fatigue' of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire), as previous research in this dataset has shown that the intervention improved cognition only in these patients.

RESULTS

Multiple regression analyses and voxel-based morphometry revealed no significant intervention effects on brain volume, although at baseline increased physical fitness was significantly related to larger brain volume (e.g., total hippocampal volume: R = 0.32, B = 21.7 mm³, 95 % CI = 3.0 - 40.4). Subgroup analyses showed an intervention effect in highly fatigued patients. Unexpectedly, these patients had significant reductions in hippocampal volume, compared to the control group (e.g., total hippocampal volume: B = -52.3 mm³, 95 % CI = -100.3 - -4.4)), which was related to improved memory functioning (HVLT-R total recall: B = -0.022, 95 % CI = -0.039 - -0.005; ACS Wordlist Learning: B = -0.039, 95 % CI = -0.062 - -0.015).

CONCLUSIONS

No exercise intervention effects were found on hippocampal volume, hippocampal subfield volumes, cortical thickness or grey matter volume for the entire intervention group. Contrary to what we expected, in highly fatigued patients a reduction in hippocampal volume was found after the intervention, which was related to improved memory functioning. These results suggest that physical fitness may benefit cognition in specific groups and stress the importance of further research into the biological basis of this finding.

Peroperative extent of peritoneal metastases affects the surgical outcome and survival in advanced ovarian cancer

OBJECTIVE

Determining whether cytoreductive surgery (CRS) is feasible in patients with advanced ovarian cancer and whether extensive surgery is justified is challenging. Accurate patient selection for CRS based on pre- and peroperative parameters will be valuable. The aim of this study is to assess the association between the extent of peritoneal metastases as determined during surgery and completeness of interval CRS and survival.

METHODS

This single-center observational cohort study included consecutive patients with newly diagnosed stage III-IV epithelial ovarian cancer who received neoadjuvant chemotherapy and underwent interval CRS. The 7 Region Count (7RC) was recorded during surgical exploration to systematically quantify the extent of peritoneal metastases. Logistic regression analysis was performed to predict surgical outcomes, and Cox regression analysis was done for survival outcomes.

RESULTS

A total of 316 patients were included for analyses. The median 7RC was 4 (interquartile range: 2-6). Complete CRS was performed in 58%, optimal CRS in 30%, and incomplete CRS in 12% of patients. A higher 7RC was independently associated with lower odds of complete or optimal CRS in multivariable analysis (odds ratio [OR] = 0.45, 95% confidence interval [CI]: 0.33-0.63, p < 0.001). Similarly, a higher 7RC was independently associated with worse progression-free survival (hazard ratio [HR] = 1.17, 95% CI 1.08-1.26, p < 0.001) and overall survival (HR = 1.14, 95% CI 1.04-1.25, p = 0.007).

CONCLUSION

The extent of peritoneal metastases, as expressed by the 7RC during surgery, is an independent predictor for completeness of CRS and has independent prognostic value for progression-free survival and overall survival in addition to completeness of CRS.

P11.61.B Capecitabine treatment of CNS metastases from breast cancer: intracranial response and survival

Background

20-30% of breast cancer patients develop brain metastases (BM) and 5% leptomeningeal metastases (LM). Incidence of BM and/or LM is dependent on breast cancer subtype. Treatment of BM consists of local treatment (resection and/or radiotherapy) and if possible systemic therapy. LM can be treated with radiotherapy of the symptomatic location of the nervous system and/or systemic therapy. Capecitabin is effective for both systemic metastases and BM of HER2-positive breast cancer. The effect of capecitabine in the non-HER2-positive breast cancers and in the LM group is largely unknown. The goal of this study is to determine the intracranial response of capecitabine and survival in HM and/or LM of the various breast cancer subtypes.

Material and Methods

breast cancer patients with HM and/or LM treated with capecitabine were selected retrospectively from a breast cancer patient cohort treated at the Netherlands Cancer Institute - Antoni van Leeuwenhoek between 2005 and 2020. Follow-up MRI scans of the brains were performed in all patients. The primary endpoints were intracranial response, intracranial progression-free survival (PFS) and overall survival (OS). Subgroup analyses for breast cancer subtypes and BM and LM patient groups were done.

Results

93 of 381 patients treated for CNS metastases of breast cancer fulfilled the inclusion criteria. Sixty-one patients (66%) had HM only, 13 (14%) had LM only and 19 patients (20%) had both HM and LM. Forty-six percent of patients had HER2-positive breast cancer, 26% had hormone receptor-positive breast cancer and 28% of patients had a triple negative subtype. After three months of capecitabine treatment intracranial response was 53%. Median OS in the patient group with intracranial response was 16.5 months versus 4.5 months in the non-response group. The hazard ratio (HR) for the median OS, corrected for radiotherapy and concurrently administered, other systemic therapy was 0.33 (95% CI: 0.17-0.67). Median intracranial PFS was 7.3 months in the response group versus 1.4 months in the non-response group (p&lt;0.001).The corrected HR for median intracranial PFS 0.13 (95% CI 0.06-0.27). The HER2-positive subtype group showed the longest median OS (22 months) as compared to the other subtypes (OS in hormone-receptor positive and triple negative subtype both 12 months)

Conclusion

Fifty-three percent of breast cancer patients with HM and/or LM treated with capecitabine demonstrate an intracranial response after three months of treatment. HER2+ breast cancer patients with HM and/or LM have a longer survival than patients with hormone receptor-positive or triple negative breast cancer subtypes.

Efficacy of subsequent chemotherapy for patients with BRCA1/2-mutated recurrent epithelial ovarian cancer progressing on olaparib versus placebo maintenance: post-hoc analyses of the SOLO2/ENGOT Ov-21 trial

BACKGROUND

In the SOLO2 trial (ENGOT Ov-21; NCT01874353), maintenance olaparib in patients with platinum-sensitive relapsed ovarian cancer (PSROC) and BRCA mutation significantly improved progression-free survival (PFS) and prolonged overall survival (OS). Following disease progression on olaparib, efficacy of subsequent chemotherapy remains unknown.

PATIENTS AND METHODS

We conducted a post-hoc hypothesis-generating analysis of SOLO2 data to determine the efficacy of different chemotherapy regimens following RECIST disease progression in patients who received olaparib or placebo. We evaluated time to second progression (TTSP) calculated from the date of RECIST progression to the next progression/death.

RESULTS

The study population comprised 147 patients who received chemotherapy as their first subsequent treatment after RECIST progression. Of these, 69 (47%) and 78 (53%) were originally randomized to placebo and olaparib arms, respectively. In the placebo-treated cohort, 27/69 and 42/69 received non-platinum and platinum-based chemotherapy, respectively, compared with 24/78 and 54/78, respectively, in the olaparib-treated cohort. Among patients treated with chemotherapy (N = 147), TTSP was significantly longer in the placebo than in the olaparib arm: 12.1 versus 6.9 months [hazard ratio (HR) 2.17, 95% confidence interval (CI) 1.47-3.19]. Similar result was obtained on multivariable analysis adjusting for prognostic factors at RECIST progression (HR 2.13, 95% CI 1.41-3.22). Among patients treated with platinum-based chemotherapy (n = 96), TTSP was significantly longer in the placebo arm: 14.3 versus 7.0 months (HR 2.89, 95% CI 1.73-4.82). Conversely, among patients treated with non-platinum-based chemotherapy (n = 51), the TTSP was comparable in the placebo and olaparib arms: 8.3 versus 6.0 months (HR 1.58, 95% CI 0.86-2.90).

CONCLUSIONS

Following progression from maintenance olaparib in the recurrent setting, the efficacy of platinum-based subsequent chemotherapy seems to be reduced in BRCA1/2-mutated patients with PSROC compared to patients not previously receiving poly (ADP-ribose) polymerase inhibitors (PARPi). The optimal strategy for patients who relapse after PARPi is an area of ongoing research.

Concurrent chemo-endocrine treatment for early hormone-positive breast cancer: a no-go???

PURPOSE

Endocrine therapy is one of the cornerstones of early breast cancer treatment. While this medication could be initiated on the day of diagnosis, it is often postponed until after completion of surgery, radiotherapy, and chemotherapy. This practice is based on preclinical data suggesting an antagonistic effect between endocrine therapy and cytostatic agents, and on the interpretation of clinical trials comparing concurrent versus sequential use of tamoxifen and chemotherapy. These clinical trials, however, have never shown a statistically significant difference in overall survival or disease-free survival and focused on tamoxifen rather than aromatase inhibitors. Nevertheless, sequentially administered endocrine and chemotherapy have become standard of care worldwide.

RESULTS

We performed a literature review and conclude that concurrent endocrine chemotherapy is at least as effective as sequential treatment. In fact, higher response rates have been observed in trials with aromatase inhibitors rather than tamoxifen in a neoadjuvant setting.

CONCLUSION

We encourage breast cancer oncologists to re-consider concurrent endocrine chemotherapy as a possible treatment strategy enabling early start of potentially curative endocrine treatment.

Toward omitting sentinel lymph node biopsy after neoadjuvant chemotherapy in patients with clinically node-negative breast cancer

BACKGROUND

The nodal positivity rate after neoadjuvant chemotherapy (ypN+) in patients with clinically node-negative (cN0) breast cancer is low, especially in those with a pathological complete response of the breast. The aim of this study was to identify characteristics known before surgery that are associated with achieving ypN0 in patients with cN0 disease. These characteristics could be used to select patients in whom sentinel lymph node biopsy may be omitted after neoadjuvant chemotherapy.

METHODS

This cohort study included patients with cT1-3 cN0 breast cancer treated with neoadjuvant chemotherapy followed by breast surgery and sentinel node biopsy between 2013 and 2018. cN0 was defined by the absence of suspicious nodes on ultrasound imaging and PET/CT, or absence of tumour cells at fine-needle aspiration. Univariable and multivariable logistic regression analyses were performed to determine predictors of ypN0.

RESULTS

Overall, 259 of 303 patients (85.5 per cent) achieved ypN0, with high rates among those with a radiological complete response (rCR) on breast MRI (95·5 per cent). Some 82 per cent of patients with hormone receptor-positive disease, 98 per cent of those with triple-negative breast cancer (TNBC) and all patients with human epidermal growth factor receptor 2 (HER2)-positive disease who had a rCR achieved ypN0. Multivariable regression analysis showed that HER2-positive (odds ratio (OR) 5·77, 95 per cent c.i. 1·91 to 23·13) and TNBC subtype (OR 11·65, 2·86 to 106·89) were associated with ypN0 status. In addition, there was a trend toward ypN0 in patients with a breast rCR (OR 2·39, 0·95 to 6·77).

CONCLUSION

The probability of nodal positivity after neoadjuvant chemotherapy was less than 3 per cent in patients with TNBC or HER2-positive disease who achieved a breast rCR on MRI. These patients could be included in trials investigating the omission of sentinel node biopsy after neoadjuvant chemotherapy.

Ribociclib plus fulvestrant for postmenopausal women with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer in the phase III randomized MONALEESA-3 trial: updated overall survival

BACKGROUND

Ribociclib plus fulvestrant demonstrated significant progression-free survival (PFS) and overall survival (OS) benefits in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced breast cancer (ABC). Here we present a new landmark in survival follow-up for a phase III cyclin-dependent kinases 4 and 6 inhibitor clinical trial in patients with ABC (median, 56.3 months).

PATIENTS AND METHODS

This phase III, randomized, double-blind, placebo-controlled trial was conducted at 174 sites (30 countries). Patients were men and postmenopausal women (age ≥18 years) with histologically/cytologically confirmed HR+/HER2- ABC. Patients could have received ≤1 line of endocrine therapy (ET) but no chemotherapy for ABC. Patients, assigned 2:1, were stratified by the presence/absence of liver/lung metastases and previous ET. Patients received intramuscular fulvestrant (500 mg, day 1 of each 28-day cycle plus day 15 of cycle 1) with oral ribociclib (600 mg/day, 3 weeks on, 1 week off) or placebo. Efficacy analyses were by intention to treat. Safety was assessed in patients receiving ≥1 dose study treatment. OS was a secondary endpoint. MONALEESA-3 is registered with ClinicalTrials.gov (NCT02422615; no longer enrolling).

RESULTS

Between 18 June 2015 and 10 June 2016, 726 patients were randomly assigned (484, ribociclib; 242, placebo). At data cut-off (30 October 2020), median OS (mOS) was 53.7 months (ribociclib) versus 41.5 months (placebo) [hazard ratio (HR), 0.73; 95% confidence interval (CI) 0.59-0.90]. Subgroup analyses were consistent with overall population. In the first-line setting, most patients in the ribociclib arm (∼60%) lived longer than median follow-up; mOS was 51.8 months in the placebo arm (HR, 0.64; 95% CI 0.46-0.88). In the second-line setting, mOS was 39.7 months (ribociclib) versus 33.7 months (placebo) (HR, 0.78; 95% CI 0.59-1.04). No apparent drug-drug interaction between ribociclib and fulvestrant or new safety signals were observed.

CONCLUSIONS

This analysis reported extended OS follow-up in MONALEESA-3. mOS was ∼12 months longer in patients with HR+/HER2- ABC treated with ribociclib plus fulvestrant compared with fulvestrant monotherapy.

Peroperative scoring systems for predicting the outcome of cytoreductive surgery in advanced-stage ovarian cancer - A systematic review

The extent of peritoneal metastases (PM) largely determines the possibility of complete or optimal cytoreductive surgery in advanced ovarian cancer. An objective scoring system to quantify the extent of PM can help clinicians to decide whether or not to embark on CRS. Therefore several scoring systems have been developed by different research teams and this review summarizes their performance in predicting a complete or optimal cytoreduction in patients with advanced ovarian cancer. A systematic search in the MEDLINE database revealed 19 articles that described a total of five main scoring systems to predict the completeness of CRS in patients with FIGO stage III-IV ovarian cancer based on the surgical exploration of the abdominal cavity; PCI, PIV, Eisenkop, Espada, and Kasper. The Peritoneal Cancer Index (PCI) and the Predictive Index Value (PIV) were mentioned most frequently and showed AUCs of 0.69-0.92 and 0.66-0.98, respectively. Due to the use of different cut-offs sensitivities and specificities greatly varied. Therefore with the current data, no scoring system could be identified as best. An objective measure of the extent of disease can be of great clinical use for identifying ovarian cancer patients for which a complete (or optimal) CRS is achievable, however due to local differences in treatment strategies and surgical policy a widely adopted objective scoring system with a standard cut-off value is not feasible. Nevertheless, objective scoring systems can play an important role to guide treatment decisions.

Intraperitoneal treatment for advanced ovarian cancer, the Dutch experience. What did we learn?

BACKGROUND

Combined administration of intravenous (iv) and intraperitoneal (ip) (iv/ip) chemotherapy is an effective adjuvant treatment option after primary debulking surgery (PDS) for advanced ovarian cancer (OC). Increased toxicityand patient burden limit its use in daily practice.

OBJECTIVE

To assess toxicity and survival outcomes of iv/ip chemotherapy in daily practice in the Netherlands.

METHODS

This retrospective cohort study included 81 women who underwent at least an optimal PDS for FIGO stage III OC followed by iv/ip chemotherapy according to the Armstrong regimen, in four hospitals in the Netherlands between January 2007 and May 2016. We collected information on surgical procedure, abdominal port implantation, toxicity, and recurrence-free and overall survival.

RESULTS

All participants underwent PDS, of whom 60 (74%) had their ip catheter implanted during PDS. Most frequently reported all grade toxicity was haematological n = 44 (54%). Forty-four patients (54%) completed all six cycles of iv/ip chemotherapy. The most frequent causes of discontinuation of iv/ip administration were renal dysfunction (12/37 = 32%) and catheter problems (7/37 = 19%). Median recurrence-free survival and overall survival were 24 months (range 0 - 108) and 80 months (range 4-115), respectively. Surgical outcome, completion of more than three courses of treatment and intra-abdominal localisation of recurrent disease were associated with better survival outcomes.

CONCLUSION

In daily practice, 54% of patients with advanced OC could complete all scheduled cycles of iv/ ip chemotherapy with acceptable morbidity and toxicity, leading to outcomes comparable with the results of published trials on iv/ip chemotherapy.

Feasibility and outcomes of a goal-directed physical therapy program for patients with metastatic breast cancer

PURPOSE

To evaluate the feasibility and outcomes of a tailored, goal-directed, and exercise-based physical therapy program for patients with metastatic breast cancer (MBC).

METHODS

This was an observational, uncontrolled feasibility study. The physical therapy intervention was highly tailored to the individual patient's goals, abilities, and preferences and could include functional, strength, aerobic, and relaxation exercises. Feasibility outcomes were participation rate (expected: 25%), safety, and adherence (percentage of attended sessions relative to scheduled sessions). Additional outcomes were goal attainment, self-reported physical functioning, fatigue, health-related quality of life, and patient and physical therapist satisfaction with the program.

RESULTS

Fifty-five patients (estimated participation rate: 34%) were enrolled. Three patients did not start the intervention due to early disease progression. An additional 22 patients discontinued the program prematurely, mainly due to disease progression. Median intervention adherence was 90% and no major intervention-related adverse events occurred. A goal attainment score was available for 42 patients (of whom 29 had completed the program and 13 had prematurely dropped out). Twenty-two (52%) of these patients achieved their main goal fully or largely and an additional 15 patients (36%) partially. Eighty-five percent would "definitely recommend" the program to other patients with MBC. We observed a modest improvement in patient satisfaction with physical activities (Cohen's d_z 0.33).

CONCLUSION

The tailored intervention program was feasible in terms of uptake, safety, and outcomes and was highly valued by patients and physical therapists. However, disease progression interfered with the program, leading to substantial dropout.

TRIAL REGISTRATION

NTR register: NTR6475.

Abstract GS5-06: Towards omitting breast surgery in patients with a pathologic complete response after neoadjuvant systemic treatment: interim analysis of the MICRA trial (Minimally Invasive Complete Response Assessment)

Background and Objectives: Improvements in neoadjuvant systemic therapy (NST) for breast cancer patients have led to increasing rates of pathologic complete response (pCR). In patients with an excellent response, imaging alone is not reliable enough to differentiate between patients with residual disease, who should be surgically treated or patients with pCR where surgery could be considered overtreatment. Several trials currently investigate the accuracy of minimal invasive biopsies to assess presence of pCR of the breast. We initiated the MICRA trial (Minimal Invasive Complete Response Assessment NTR6120) combining MRI and minimal invasive biopsies of the breast.

Methods: Breast cancer patients treated with NST resulting in a radiologic complete (rCR) or partial response (rPR, &gt; 30 % decrease and &lt; 2 cm residual diameter) on MRI are eligible. Post-NST, eight ultrasound-guided 14G core biopsies of the pre-NST marked tumor area are obtained. Pathology results of biopsies and surgical specimens are compared. The primary endpoint is the false-negative rate (FNR) of the biopsy procedure i.e. the proportion of patients with non-pCR in the surgical specimen but with pCR in the biopsies. Here we report results of the interim analysis.

Results: 219 patients were enrolled in the trial. Biopsies were successfully obtained and analyzed in 167 patients. Main age was 49 yrs (range 24-74). Tumor subtype was 26% hormone receptor positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-), 14% HR-/HER2+, 36% triple negative and 24% HR+HER2+. 135 patients had a rCR and 32 patients a rPR on MRI. There were 89 patients (53%) with pCR in the surgical specimen, all correctly identified by post-NST biopsies (false-positive rate 0%). Post-NST biopsies however missed residual disease in 29/78 patients (FNR 37%). FNR was higher in patients with rCR (FNR 45%; 26/55 patients with residual disease missed on biopsies) than in patients with rPR (FNR 13 %; 3/23 patients with residual disease missed with biopsies). The conditional power estimating the probability of the FNR being ≤ 8% at final analysis was &lt; 1%.

MICRA patients total n=167Specimen negSpecimen posBiopsy neg8929118FNR= 29/7837%Biopsy pos049498978167

Conclusions: Ultrasound-guided core biopsies of the breast in patients with excellent response on MRI after NST are not accurate enough to safely select patients with pCR for omission of surgery.

Citation Format: Marie-Jeanne T.F.D. Vrancken Peeters, A van Loevezijn, M EM van der Noordaa, F H van Duijnhoven, C E Loo, E van Werkhoven, K K van de Vijver, T Wiersma, H AO Winter-Warnars, G S Sonke, C. Blanken, B. Zonnevels. Towards omitting breast surgery in patients with a pathologic complete response after neoadjuvant systemic treatment: interim analysis of the MICRA trial (Minimally Invasive Complete Response Assessment) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS5-06.

Radiological complete remission in HER2-positive metastatic breast cancer patients: what to do with trastuzumab?

PURPOSE

Patients with HER2-positive metastatic breast cancer (MBC) treated with trastuzumab may experience durable tumor response for many years. It is unknown if patients with durable radiological complete remission (rCR) can discontinue trastuzumab. We analyzed clinical characteristics associated with rCR and overall survival (OS) in a historic cohort of patients with HER2-positive MBC and studied the effect of stopping trastuzumab in case of rCR.

METHODS

We included patients with HER2-positive MBC treated with first or second-line trastuzumab-based therapy in eight Dutch hospitals between 2000 and 2014. Data were collected from medical records. We used multivariable regression models to identify independent prognostic factors for rCR and OS. Time-to-progression after achieving rCR for patients who continued and stopped trastuzumab, and breast cancer-specific survival were also evaluated.

RESULTS

We identified 717 patients with a median age of 53 years at MBC diagnosis. The median follow-up was 109 months (IQR 72-148). The strongest factor associated with OS was achievement of rCR, adjusted hazard ratio 0.27 (95% CI 0.18-0.40). RCR was observed in 72 patients (10%). The ten-year OS estimate for patients who achieved rCR was 52 versus 7% for patients who did not achieve rCR. Thirty patients with rCR discontinued trastuzumab, of whom 20 (67%) are alive in ongoing remission after 78 months of median follow-up since rCR. Of forty patients (58%) who continued trastuzumab since rCR, 13 (33%) are in ongoing remission after 68 months of median follow-up. Median time-to-progression in the latter group was 14 months.

CONCLUSIONS

Achieving rCR is the strongest predictor for improved survival in patients with HER2-positive MBC. Trastuzumab may be discontinued in selected patients with ongoing rCR. Further research is required to identify patients who have achieved rCR and in whom trastuzumab may safely be discontinued.

Effects and moderators of exercise on sleep in adults with cancer: Individual patient data and aggregated meta-analyses

OBJECTIVES

To evaluate the effects of exercise interventions on sleep disturbances and sleep quality in patients with mixed cancer diagnoses, and identify demographic, clinical, and intervention-related moderators of these effects.

METHODS

Individual patient data (IPD) and aggregated meta-analyses of randomized controlled trials (RCTs). Using data from the Predicting OptimaL cAncer RehabIlitation and Supportive care project, IPD of 2173 adults (mean age = 54.8) with cancer from 17 RCTs were analyzed. A complementary systematic search was conducted (until November 2018) to study the overall effects and test the representativeness of analyzed IPD. Effect sizes of exercise effects on self-reported sleep outcomes were calculated for all included RCTs. Linear mixed-effect models were used to evaluate the effects of exercise on post-intervention outcome values, adjusting for baseline values. Moderator effects were studied by testing interactions for demographic, clinical and intervention-related characteristics.

RESULTS

For all 27 eligible RCTs from the updated search, exercise interventions significantly decreased sleep disturbances in adults with cancer (g = -0.09, 95% CI [-0.16; -0.02]). No significant effect was obtained for sleep quality. RCTs included in IPD analyses constituted a representative sample of the published literature. The intervention effects on sleep disturbances were not significantly moderated by any demographic, clinical, or intervention-related factor, nor by sleep disturbances.

CONCLUSIONS

This meta-analysis provides some evidence that, compared to control conditions, exercise interventions may improve sleep disturbances, but not sleep quality, in cancer patients, although this effect is of a small magnitude. Among the investigated variables, none was found to significantly moderate the effect of exercise interventions on sleep disturbances.

Perioperative change in CA125 is an independent prognostic factor for improved clinical outcome in advanced ovarian cancer

OBJECTIVE

Despite being the most important prognostic factor for prolonged overall survival in epithelial ovarian cancer (EOC), the measurement of residual disease is hampered by its subjective character. Additional assessment tools are needed to establish the success of cytoreductive surgery in order to predict patients' prognosis more accurately. The aim of this study is to evaluate the independent prognostic value of perioperative CA125 change in advanced stage EOC patients.

STUDY DESIGN

We identified all patients who underwent primary cytoreductive surgery for advanced stage (FIGO IIB-IV) EOC between 2008 and 2015, from the Netherlands Cancer Registry. The relative perioperative change in CA125 was categorized into four groups; increase, <50% decline, 50-79% decline and ≥80% decline. Overall survival (OS) was analyzed using Kaplan-Meier survival curves and multivariable cox regression models.

RESULTS

We included 1232 eligible patients with known pre- and postoperative CA125 serum levels. Patients with a decline of ≥80% in CA125 levels experienced improved OS compared to those with a decline of <50% (univariable Hazard Ratio (HR) 0.45, 95%CI 0.36-0.57). The prognostic effect of perioperative CA125 change was independent of patient- and treatment characteristics, such as the extent of residual disease after cytoreductive surgery (multivariable HR_≥80% 0.52(0.41-0.66)).

CONCLUSIONS

This study shows that the perioperative change in CA125 is an independent prognostic factor for overall survival after primary surgery for EOC patients. This pleads for the use of a combined model, consisting of perioperative CA125 change and the outcome of residual disease, in order to predict the prognosis of EOC patients more accurately.

Antitumor activity and safety of pembrolizumab in patients with advanced recurrent ovarian cancer: results from the phase II KEYNOTE-100 study

BACKGROUND

Advanced recurrent ovarian cancer (ROC) is the leading cause of gynecologic cancer-related death in developed countries and new treatments are needed. Previous studies of immune checkpoint blockade showed low objective response rates (ORR) in ROC with no identified predictive biomarker.

PATIENTS AND METHODS

This phase II study of pembrolizumab (NCT02674061) examined two patient cohorts with ROC: cohort A received one to three prior lines of treatment with a platinum-free interval (PFI) or treatment-free interval (TFI) between 3 and 12 months and cohort B received four to six prior lines with a PFI/TFI of ≥3 months. Pembrolizumab 200 mg was administered intravenously every 3 weeks until cancer progression, toxicity, or completion of 2 years. Primary end points were ORR by Response Evaluation Criteria in Solid Tumors version 1.1 per blinded independent central review by cohort and by PD-L1 expression measured as combined positive score (CPS). Secondary end points included duration of response (DOR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Cohort A enrolled 285 patients; the first 100 served as the training set for PD-L1 biomarker analysis. Cohort B enrolled 91 patients. ORR was 7.4% for cohort A and 9.9% for cohort B. Median DOR was 8.2 months for cohort A and not reached for cohort B. DCR was 37.2% and 37.4%, respectively, in cohorts A and B. Based on the training set analysis, CPS 1 and 10 were selected for evaluation in the confirmation set. In the confirmation set, ORR was 4.1% for CPS <1, 5.7% CPS ≥1, and 10.0% for CPS ≥10. PFS was 2.1 months for both cohorts. Median OS was not reached for cohort A and was 17.6 months for cohort B. Toxicities were consistent with other single-agent pembrolizumab trials.

CONCLUSIONS

Single-agent pembrolizumab showed modest activity in patients with ROC. Higher PD-L1 expression was correlated with higher response.

CLINICAL TRIAL NUMBER

Clinicaltrials.gov, NCT02674061.

Health-related quality of life after interval cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with stage III ovarian cancer

INTRODUCTION

The addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to interval cytoreductive surgery (CRS) improves recurrence-free (RFS) and overall survival (OS) in patients with FIGO stage III ovarian cancer. We evaluated the effect of HIPEC on patient's health-related quality of life (HRQoL) in the OVHIPEC trial.

MATERIALS AND METHODS

OVHIPEC was a multicentre, open-label, randomized phase III trial for patients with stage III ovarian cancer. Patients were randomly assigned (1:1) to receive interval CRS with or without HIPEC with cisplatin. HRQoL was assessed using the EORTC QLQ-C30, and the ovarian (QLQ-OV28) and colorectal cancer (QLQ-CR38) modules. HRQoL questionnaires were administered at baseline, after surgery, after end of treatment, and every three months thereafter. HRQoL was a secondary endpoint, with the prespecified focus on the QLQ-C30 summary score and symptom scores on fatigue, neuropathy and gastro-intestinal symptoms. HRQoL was analysed using linear and non-linear mixed effect models.

RESULTS

In total, 245 patients were randomized. One-hundred-ninety-seven patients (80%) completed at least one questionnaire. No significant difference over time in the QLQ-C30 summary scores was observed between the study arms (p-values for linear and non-linear growth: p > 0.133). The pattern over time for fatigue, neuropathy and gastro-intestinal symptoms did not significantly differ between treatment arms.

CONCLUSION

The addition of HIPEC to interval CRS does not negatively impact HRQoL in patients with stage III ovarian cancer who are treated with interval CRS due to the extent of disease. These HRQoL results, together with the improvement in RFS and OS, support the viability of HIPEC as an important treatment option in this patient population. CLINICALTRIALS.

GOV NUMBER

NCT00426257.

EUDRACT NUMBER

2006-003466-34.

Outcome of surgery in advanced ovarian cancer varies between geographical regions; opportunities for improvement in The Netherlands

INTRODUCTION

The care for patients with epithelial ovarian cancer(EOC) is organised in eight different geographical regions in the Netherlands. This situation allows us to study differences in practice patterns and outcomes between geographical regions for patients with FIGO stage IIIC and IV.

METHODS

We identified all EOC patients who were diagnosed with FIGO stage IIIC or IV between 01.01.2008 and 31.12.2015 from the Netherlands Cancer Registry. Descriptive statistics were used to summarize treatment and treatment sequence(primary cytoreductive surgery(PCS) or neoadjuvant chemotherapy and interval cytoreductive surgery(NACT-ICS)). Moreover, outcome of surgery was compared between geographical regions. Multilevel logistic regression was used to assess whether existing variation is explained by geographical region and case-mix factors.

RESULTS

Overall, 6,741 patients were diagnosed with FIGO IIIC or IV disease. There were no differences in the percentage of patients that received any form of treatment between the geographical regions(range 80-86%, P = 0.162). In patients that received cytoreductive surgery and chemotherapy, a significant variation between the geographical regions was observed in the use of PCS and NACT-ICS(PCS: 24-48%, P < 0.001). The percentage of complete cytoreductive surgeries after PCS ranged from 10 to 59%(P < 0.001) and after NACT-ICS from 37 to 70%(P < 0.001). Moreover, geographical region was independently associated with the outcome of surgery, also when adjusted for treatment sequence(P < 0.001).

CONCLUSION

We observed a significant variation in treatment approach for advanced EOC between geographical regions in the Netherlands. Furthermore, the probability to achieve no residual disease differed significantly between regions, regardless of treatment sequence. This may suggest that surgical outcomes can be improved across geographical regions.

Abstract OT2-01-04: Towards omitting breast cancer surgery in patients with pathologic complete response after neoadjuvant systemic therapy: The MICRA trial (minimally invasive complete response assessment)

Background

Improvements in neoadjuvant systemic therapy (NST) for breast cancer patients have led to increasing rates of pathologic complete response (pCR). Breast-conserving surgery (BCS) after NST is considered safe, despite the fact that the original tumor bed is not entirely excised. It can therefore be hypothesized that breast surgery could be omitted in patients achieving pCR. However, since imaging modalities are insufficiently accurate to predict pCR after NST, the need for surgery is unchanged. The MICRA trial is designed to determine the value of ultrasound guided biopsy of the breast in identifying pCR after NST. The ultimate aim of our study is to eliminate surgery of the breast in patients achieving pCR, consequently improving quality of life of these patients.

Trial design

The MICRA trial is a multi-center observational prospective cohort study. Inclusion and exclusion criteria are presented in table 1. In all patients receiving NST, a marker is placed in the center of the tumor area pre-NST. Magnetic resonance imaging (MRI) is performed pre-NST and just before or after the last course of NST. Patients with radiologic complete response (rCR; complete absence of pathologic contrast enhancement) or partial response (rPR, 0.1-2.0 cm residual contrast enhancement, ≥30% decrease in tumour size) are eligible for participation. In these patients, 8 ultrasound guided biopsies are obtained in the region surrounding the marker: 4 central (&lt;0.5 cm) and 4 peripheral biopsies (0.5-1.5cm). Hereafter, conventional surgery is performed (BCS or mastectomy) and pathology results of the biopsies and resected specimen are compared. Pathology findings are scored using Miller-Payne criteria. To evaluate the quality and representativeness of the biopsies, biopsies are categorized according to length and pathology results.

Statistical analysis and accrual

The primary endpoint of the trial is the false-negative rate (FNR) of the biopsy procedure. If the true FNR is 3%, 130 patients without pCR in specimen are sufficient to show that the FNR does not exceed 8% using a one-sided binomial test with a significance α-level of 0.05. With an expected average pCR rate of 65%, 375 patients with rCR will be included. In the rPR-group the expected pCR rate is 12% and therefore 150 patients will be included. In total 525 patients will be included. Until now, 144 patients have been included.

Conclusion

The ultimate aim of the MICRA trial is to eliminate surgery of the breast in patients achieving pCR, by identifying pCR with use of ultrasound guided biopsy. In this scenario, local therapy in patients with pCR would be restricted to radiotherapy.

Table 1:Inclusion and exclusion criteriaInclusion criteriaExclusion criteriaWomen with invasive breast cancer &gt;18 years (all histological subtypes and tumor subtypes)DCIS as shown by core biopsy prior to NSTTumor histology and receptor status established by pre-NST biopsyWomen with distant metastatic diseaseComplete or partial response on post-NST MRIHistory of ipsilateral breast cancerMarker placed in tumor prior to NST Correct position of marker confirmed by mammography or ultrasound 

Citation Format: van der Noordaa ME, van Duijnhoven FH, Loo CE, van Loevezijn A, van Werkhoven E, van de Vijver KK, Wiersma T, Winter-Warnars HA, Sonke GS, Vrancken Peeters M-JT. Towards omitting breast cancer surgery in patients with pathologic complete response after neoadjuvant systemic therapy: The MICRA trial (minimally invasive complete response assessment) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-01-04.

Abstract P6-17-19: What to do with trastuzumab therapy after achieving radiological complete remission (rCR) in HER2+ metastatic breast cancer (MBC)?

Intro MBC is generally considered incurable, but patients with HER2+ disease treated with trastuzumab do relatively well and some have an exceptional durable response and survive over 10 years. We analyzed the clinical-pathological characteristics associated with long-term survival in patients with HER2+ MBC treated with trastuzumab. In addition, we studied the effect of stopping trastuzumab in case of rCR.

Methods We included all patients with HER2+ MBC treated with first- or second-line trastuzumab-based palliative therapy between January 2000 and December 2014 in 8 Dutch hospitals (Netherlands Cancer Institute, Erasmus Medical Center, Albert Schweitzer Hospital, Reinier de Graaf Hospital, Amphia Hospital, St. Antonius Hospital, Ikazia Hospital, Haga Hospital). Patients were identified through the Netherlands Cancer Registry and linkage with the institutes' tumor registries. Data was collected from medical records using case record forms. Primary endpoint was overall survival (OS), defined as first-date of MBC until death due to any cause. Kaplan-Meier survival estimates were calculated and multivariable Cox-regression models used to identify prognostic factors for improved survival. Time to progression (TTP) after achieving rCR for patients who continued and stopped trastuzumab and breast cancer specific survival were secondary outcomes.

Results We included 744 patients (median age 53, range 24-87). Median follow-up (FU) was 109 months (range 0-178). Clinical factors associated with improved survival in multivariable analyses were single-organ metastases, ER-positivity, no skin or liver metastases, no prior trastuzumab, local therapy of metastatic disease and achievement of rCR. In line with our first single center analyses1, achievement of rCR was the strongest predictor of improved survival (multivariable HR 0.30, 95%CI 0.20-0.46). RCR was observed in 71 patients (10%), of whom 60 had been treated with trastuzumab and chemotherapy, 9 with trastuzumab and hormonal therapy, and 2 with hormonal therapy. In patients with rCR the estimated 10-year OS was 53% versus 7% in patients who did not achieve rCR (p&lt;0.001).

Thirty patients stopped trastuzumab after achieving rCR. Median time between onset of rCR and last gift of trastuzumab in these patients was 6 months (0-132). Twenty-one patients (70%) remain in complete remission after a median FU of 75 months (range 54-90) since onset of rCR. Nine patients experienced disease progression after a median time of 14 months (range 9-62) since last gift of trastuzumab. Of these, 8 patients died due to MBC and one again achieved an ongoing rCR. Out of 39 patients who continued trastuzumab after achieving rCR, 12 are in ongoing remission after a median FU of 71 months (range 51-91). In this group median TTP was 14 months (range 5-23).

Conclusion Achieving rCR is strongly associated with long-term survival in patients with HER2+ MBC. Seventy percent of patients who stopped trastuzumab after achieving rCR remained in remission, suggesting this can be an attractive approach in selected patients. External validation of these findings is required, however, as well as additional analyses to characterize the patients -and their tumors- who achieved rCR.

1 Steenbruggen, CancerRes 2017

Citation Format: Steenbruggen TG, Bouwer NI, Smorenburg CH, Rier HN, Jager A, Beelen KJ, ten Tije AJ, de Jong PC, Drooger JC, Holterhues C, Horlings HM, Sanders J, Levin M-D, Sonke GS. What to do with trastuzumab therapy after achieving radiological complete remission (rCR) in HER2+ metastatic breast cancer (MBC)? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-19.

Abstract OT3-02-04: Selecting the optimal position of CDK4/6 inhibitors in hormone-receptor-positive advanced breast cancer: The BOOG 2017-03 SONIA study

BACKGROUND

Combining cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors with endocrine therapy (ET) is an effective strategy to improve progression-free survival (PFS) in hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC). There is a lack of comparative data to help clinicians decide whether CDK4/6 inhibitors can best be added to first- or second-line ET. The former strategy may provide longer PFS benefit, but is associated with longer use of the drug, which results in more toxicity and costs, whereas no clear benefit on overall survival (OS) or quality of life (QoL) has been proven thus far. No predictive biomarker exists to select patients who are most likely to benefit from the addition of CDK4/6 inhibition.

TRIAL DESIGN AND AIMS

The SONIA study is an investigator-initiated, multicenter, randomized phase III study, funded by 'ZonMw' and 'Zorgverzekeraars Nederland'. Patients are randomly assigned to receive either strategy A (first-line treatment with a non-steroidal aromatase inhibitor (NSAI) + CDK4/6 inhibition, followed on progression by fulvestrant) or strategy B (first-line treatment with NSAI, followed on progression by fulvestrant + CDK4/6 inhibition). Each CDK4/6 inhibitor can be used according to its approved EMA label. The primary objective is to test whether strategy A is superior to strategy B. The primary endpoint is time from randomization to second objective progression (PFS2). Secondary endpoints include OS, safety, QoL, and cost-effectiveness. Additional biomarker analyses will be performed to optimize patient selection.

ELIGIBILITY CRITERIA

Patients with a proven diagnosis of HR+/HER2-negative advanced breast cancer without prior systemic therapy for advanced disease who are candidates to receive NSAIs as first-line treatment, are eligible for the study. Exclusion criteria include advanced visceral spread with the risk of life-threatening complications in the short term. Other conditions excluding a patient from participating are other malignancies, prolonged QTc time (&gt;480ms) or any other medical condition that interferes with study procedures or compliance.

STATISTICAL METHODS

The difference in PFS2 will be estimated using the intention-to-treat population in a Cox proportional hazards model accounting for all stratification factors (visceral versus non-visceral disease, yes versus no prior ET in (neo)adjuvant setting, hospital, and type of CDK4/6 inhibitor). Five-hundred seventy-four primary outcome events yield 89% power to show that strategy A has statistically significant, clinically meaningful (according to European Society for Medical Oncology - Magnitude of Clinical Benefit Scale) superior PFS2 in a log-rank test at the two-sided 95% confidence level.

ACCRUAL

TARGET: with an accrual period of 42 months and an additional 18 months follow-up, inclusion of 1050 evaluable patients is required. A total of 76 Dutch hospitals will participate.

PRESENT: the study is open in 51 hospitals and 106 patients are included.

Citation Format: van Ommen - Nijhof A, van der Voort A, Konings IR, Jager A, Sonke GS, On behalf of the SONIA Investigators (SONIA Steering Committee), And the Dutch Breast Cancer Research Group (BOOG). Selecting the optimal position of CDK4/6 inhibitors in hormone-receptor-positive advanced breast cancer: The BOOG 2017-03 SONIA study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-02-04.

Abstract P6-18-07: Ribociclib + endocrine therapy in patients with hormone receptor-positive, HER2-negative advanced breast cancer presenting with visceral metastases: Subgroup analysis of phase III MONALEESA trials

Background: Patients (pts) with advanced breast cancer (ABC) who present with visceral metastases (mets) have a poorer prognosis vs pts with non-visceral disease. In the Phase III MONALEESA (ML) trials, ribociclib (RIB) + endocrine therapy (ET) prolonged progression-free survival (PFS) vs placebo (PBO) + ET in hormone receptor-positive (HR+), HER2-negative (HER2–) ABC. Here we show data for pts with and without visceral mets from the ML-2, -3, and -7 trials.

Methods: Data were collated from 3 trials in HR+, HER2– ABC: in ML-2 (NCT01958021; data cutoff [DCO] Jan 2/4, 2017), postmenopausal pts (no prior ET for ABC) received RIB or PBO + letrozole; in ML-3 (NCT02422615; DCO Nov 3, 2017), postmenopausal pts (no prior ET for ABC subgroup only) received RIB or PBO + fulvestrant; in ML-7 (NCT02278120; DCO Aug 20, 2017), premenopausal pts (no prior ET and ≤1 chemotherapy for ABC) received RIB or PBO + goserelin + anastrozole/letrozole. Endpoints; primary: local PFS; secondary: overall response rate (ORR), clinical benefit rate (CBR), safety.

Results: Of all 820 pts treated with RIB + ET, 484 (59%) had visceral mets (ML-2 197/334; ML-3 137/238; ML-7 150/248); of all 710 pts treated with PBO + ET, 416 (59%) had visceral mets (ML-2 196/334; ML-3 77/129; ML-7 143/247). Median PFS was prolonged for RIB vs PBO in pts with and without visceral mets (Table). ORR and CBR were also higher for RIB vs PBO in pts with and without visceral mets. The most common (≥10% of pts in any arm) Grade [G] 3 and 4 adverse events (AEs) for each trial are shown in the table; no G4 AEs occurred in ≥10% of pts in ML-3.

 Visceral metsNo visceral metsML-2 Median PFS (RIB/PBO), months (95% CI)24.9 (22.2–30.9)/13.4 (12.7–16.5)25.3 (22.2–NR)/18.2 (15.0–24.6)Hazard ratio (95% CI)0.538 (0.408–0.709)0.634 (0.448–0.897) ORR (RIB/PBO),* %48/3735/17 CBR (RIB/PBO),† %79/7282/75 Most common (≥10% in any arm) G3 AEs (RIB/PBO), %Neutropenia56/147/1Leukopenia19/121/&lt;1Hypertension11/1115/15 Most common (≥10% in any arm) G4 AEs (RIB/PBO), %Neutropenia10/09/0 ML-3 Median PFS (RIB/PBO), months (95% CI)NR (19.1–NR)/16.5 (9.0–NR)NR (NR–NR)/21.9 (14.8–NR)Hazard ratio (95% CI)0.610 (0.403–0.926)0.521 (0.295–0.921) ORR (RIB/PBO),* %46/2931/21 CBR (RIB/PBO),† %74/6075/81 Most common (≥10% in any arm) G3 AEs (RIB/PBO), %Neutropenia50/045/0Leukopenia12/010/0Increased ALT6/012/0 ML-7 Median PFS (RIB/PBO), months (95% CI)23.8 (14.8–NR)/10.4 (7.2–12.9)27.5 (NR–NR)/19.3 (16.5–NR)Hazard ratio (95% CI)0.507 (0.367–0.700)0.609 (0.377–0.984) ORR (RIB/PBO),* %45/3630/19 CBR (RIB/PBO),† %79/5783/81 Most common (≥10% in any arm) G3 AEs (RIB/PBO), %Neutropenia54/356/4Leukopenia14/116/1 Most common (≥10% in any arm) G4 AEs (RIB/PBO), %Neutropenia11/&lt;19/0CI, confidence interval; NR, not reached. *ORR = complete response + partial response; †CBR = complete response + partial response + (stable disease + non-complete response/non-progressive disease ≥24 weeks).

Conclusions: Although the presence of visceral mets is associated with a poorer prognosis, RIB + ET is an effective and well-tolerated treatment option for pts with HR+, HER2– ABC irrespective of the presence of visceral mets.

Citation Format: Yardley DA, Chan A, Nusch A, Sonke GS, Yap Y-S, Bachelot T, Esteva FJ, Slamon DJ, Burris HA, Gaur A, Kong O, Diaz-Padilla I, Rodriguez Lorenc K, Wheatley-Price P. Ribociclib + endocrine therapy in patients with hormone receptor-positive, HER2-negative advanced breast cancer presenting with visceral metastases: Subgroup analysis of phase III MONALEESA trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-07.

Abstract OT2-07-07: Image-guided de-escalation of neoadjuvant chemotherapy in HER2-positive breast cancer: The TRAIN-3 study

Background

The addition of pertuzumab to trastuzumab containing chemotherapy has boosted pathologic complete response (pCR) rates after neoadjuvant chemotherapy for HER2-positive breast cancer. PCR rates over 80% have been described and achieving a pCR is associated with a favorable long-term outcome. In addition, achieving a radiologic complete response (rCR) is predictive of the pathologic response in HER2-positive tumors. Therefore it is hypothesized that image-guided evaluation based on the early occurrence of rCR can be used to tailor the number of chemotherapy cycles.

Trial design

This is a single arm, multicenter study evaluating the efficacy of image-guided de-escalation of neoadjuvant treatment with paclitaxel, Herceptin®, carboplatin, and pertuzumab (PTC-ptz). Radiologic evaluation with contrast-enhanced breast MRI and ultrasound of the axilla (in cN+ patients) is performed at baseline and after 3, 6, and 9 cycles of treatment. In case of rCR of the breast (and axilla) after 3 or 6 cycles, early surgery will be performed. If residual tumor is present after 3 and 6 cycles, patients will continue the PTC-ptz regimen to complete a total of 9 cycles. All patients will receive adjuvant Herceptin® and pertuzumab to complete 1 year of anti-HER2 blockade and endocrine treatment according to local guidelines if HR-positive. The study will be performed in the Netherlands in approximately 35 centers.

Eligibility criteria

Eligible patients have histologically proven stage II/III HER2-positive primary breast cancer with known hormone-receptor status. Patients must have a measurable breast tumor on baseline MRI and can be either node negative or node positive.

Specific aims

The aim is to evaluate the efficacy of image-guided de-escalation of neoadjuvant chemotherapy in HER2-positive breast cancer on event-free survival (EFS) at 3 years as primary endpoint. Secondary endpoints are overall survival, rCR, concordance between rCR and pCR (ypT0/is, ypN0), differences in EFS and OS following pCR between patients who received 3, 6, or 9 cycles, and toxicity.

Statistical methods

This is a single-arm, two stage study with one interim-analysis and a final analysis. Statistics will be performed for each hormone receptor subgroup separately. Stopping rules are based on 3-year EFS-rates described in literature (88% for HR-negative tumors and 90% for HR-positive tumors) and calculated using the exact conditional Poisson distribution. The study is successful with ≤34 EFS-events in the HR-negative subgroup and ≤38 events in the HR-positive subgroup after 700 patient-years of follow-up. The three-year EFS-estimate will be calculated using Kaplan-Meier statistics.

Present accrual and target accrual

Target accrual is 231 patients for the HR-negative group and 231 patients for the HR-positive group. Present accrual will follow.

Funding

Investigator initiated trial sponsored by the Dutch Breast Cancer Research Group (BOOG), funded by Roche.

Contact information for people with a specific interest in the trial

Study coordinator: A van der Voort, MD

The Netherlands Cancer Institute

1006 BE Amsterdam

E: a.vd.voort@nki.nl, P:+31 20 512 2951

Citation Format: van der Voort A, Dezentjé VO, van der Steeg WA, Winter-Warnars GA, Schipper R-J, Scholten AN, Wesseling J, van Werkhoven ED, van Duijnhoven FH, Vrancken Peeters M-JT, Sonke GS. Image-guided de-escalation of neoadjuvant chemotherapy in HER2-positive breast cancer: The TRAIN-3 study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-07-07.

Abstract P6-18-06: Ribociclib treatment benefit in patients with advanced breast cancer with ≥1 dose reduction: Data from the MONALEESA-2, -3, and -7 trials

Background: In the MONALEESA (ML) trials, addition of ribociclib (RIB; cyclin-dependent kinase 4/6 inhibitor) to endocrine therapy (ET) prolonged progression-free survival (PFS) in patients (pts) with hormone receptor-positive (HR+), HER2-negative (HER2–) advanced breast cancer (ABC). RIB was generally well tolerated, with adverse events (AEs) managed effectively by dose modifications. Here we present efficacy data for RIB-based regimens of interest for the proposed indication (i.e. with a non-steroidal aromatase inhibitor [NSAI] or fulvestrant [FUL]) from ML-2, -3, and -7 in pts who received no prior ET for ABC and who had ≥1 RIB dose reduction, to explore the efficacy of RIB in pts who need to dose reduce.

Methods: Pts included in this analysis were: postmenopausal women with HR+, HER2– ABC and no prior ET for ABC who received RIB (600 mg; 3-weeks-on/1-week-off) with letrozole (2.5 mg/day; ML-2 [NCT01958021]), or FUL (500 mg per label; ML-3 [NCT02422615]); and premenopausal women with no prior ET and ≤1 line of chemotherapy for ABC who received RIB with an NSAI (anastrozole: 1 mg/day; letrozole: 2.5 mg/day; ML-7 [NCT02278120]) plus goserelin (3.6 mg every 28 days). Dose reductions for RIB (600 to 400 to 200 mg) were permitted. Primary endpoint was PFS. Secondary endpoints included overall response rate (ORR), clinical benefit rate (CBR), and safety.

Results: In ML-2, -3, and -7, ≥1 RIB dose reduction occurred (n/N) in 169/334 (51%), 92/238 (39%), and 91/246 (37%) pts assigned to RIB, respectively. AEs were the main reason for dose reduction, with all-grade neutropenia the most common AE leading to dose reduction (ML-2 69%, ML-3 80%, ML-7 82%). Median PFS (months) was prolonged with RIB vs placebo in pts without a RIB dose reduction (ML-2: 27.7 vs 16.0; ML-3: not reached [NR] vs 18.3; ML-7: 23.8 vs 13.8); median PFS in pts with ≥1 RIB dose reduction was: ML-2 25.3, ML-3 NR, and ML-7 27.5 months. In pts with measurable disease and without a RIB dose reduction, ORR was 46% (ML-2), 43% (ML-3), and 48% (ML-7); CBR was 70%, 68%, and 79%, respectively. In pts with measurable disease and ≥1 RIB dose reduction, ORR was 62% (ML-2), 57% (ML-3), and 55% (ML-7); CBR was 88%, 85%, and 88%, respectively. The most common Grade 3/4 AEs in the RIB vs placebo groups (≥5% of pts in either ML trial, irrespective of causality or dose reduction) were neutropenia (ML-2: 62% vs 1%; ML-3: 55% vs 0; ML-7: 65% vs 4%), leukopenia (ML-2: 21% vs 1%; ML-3: 12% vs 0; ML-7: 16% vs 1%), hypertension (ML-2: 13% vs 13%; ML-3: 5% vs 5%; ML-7: 2% vs 3%), increased alanine aminotransferase (ML-2: 10% vs 1%; ML-3: 10% vs 0; ML-7: 5% vs 1%), and increased aspartate aminotransferase (ML-2: 6% vs 1%; ML-3: 6% vs 0; ML-7: 4% vs 1%).

Conclusions: Results from the ML-2, -3, and -7 trials suggest that pts who start on 600 mg of RIB and require dose reduction for the management of their AEs, or for other reasons, continue to derive clinical benefit.

Citation Format: Beck JT, Neven P, Sohn J, Chan A, Sonke GS, Bachelot T, Campos-Gomez S, Martin M, Bardia A, Alam J, Miller M, Diaz-Padilla I, Kong O, Hart L. Ribociclib treatment benefit in patients with advanced breast cancer with ≥1 dose reduction: Data from the MONALEESA-2, -3, and -7 trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-06.

Abstract P2-07-04: Prognostic value of residual cancer burden (RCB), neo-bioscore and neoadjuvant response index (NRI) to evaluate response to neoadjuvant trastuzumab-based therapy in HER2-positive breast cancer (BC)

Intro Pathological complete response (pCR) to neoadjuvant systemic therapy is associated with favorable long-term outcome. As pCR is not an optimal surrogate marker for outcome, other tools were developed to predict long-term outcome more accurately, including the RCB4, NRI3, and Neo-Bioscore5. We evaluated the prognostic value of these tools in a cohort of patients with HER2+ BC with the aim of selecting a group of patients with residual disease but a similar long-term outcome as patients achieving pCR.

Methods We included all patients with stage II-III HER2+ BC who were treated with trastuzumab-based neoadjuvant therapy and surgery in the Netherlands Cancer Institute between November 2004 and December 2016. Patients were identified from the institutes' tumor registry and data was collected from the patients' records. To assess RCB scores surgical specimens (breast and axilla tissue) of patients without pCR were retrospectively reviewed. NRI and Neo-Bioscore were calculated based on original pathology reports.

Primary endpoint was recurrence-free interval (RFI), defined as time since diagnosis of BC till locoregional or distant recurrence or death from BC, whatever came first. Cox proportional models were used with transformations of RCB, NRI, and Neo-Bioscore. In addition, we evaluated at which cut-off point the NRI could select patients with a similar good prognosis as patients who achieved a pCR, defined by the same lower bound of the 95%CI of the 5-year RFI estimate for the pCR-group.

Results 283 women were included, 149 (53%) with HER2+/ER+ BC. 28% received dual HER2-blockade. Median follow-up was 66 months (range 11-148). 157 patients (55%) achieved a pCR in breast and axilla; predicted 5-year RFI for this group was 91% (95%CI 86-96), HR no-pCR vs pCR 2.19, 95%CI 1.07-4.47. Table 1 shows the predicted 5-year RFI and HR for RCB classes. The HR of an RFI event increases gradually for lower NRI values compared to NRI of 1 and gets more steep near NRI values of 0. Patients with a NRI of ≥0.80-0.99 have a 5-year RFI estimate of 90% (95%CI 86-96), HR 1.1 (95%CI 0.6-1.9) compared to patients with NRI of 1 (which is pCR). Table 2 shows the predicted 5-year RFI and HR for the Neo-Bioscore.

Table 1RCB classes, estimated 5-year RFI and HRRCBn% 5-year RFI95% CIHR95% CI016392.688.397.111113990.385.295.61.330.672.6526278.469.488.53.181.427.1131135.316.476.113.605.3034.81

Table 2Neo-Bioscore classes, predicted 5-year RFI and HRNeo-Bioscoren% 5-year RFI95% CIHR95% CI01998.795.510011115392.486.099.36.100.9240.5229384.977.493.012.670.76210.4037289.983.896.58.200.62108.2041974.962.989.222.331.76283.445329.410.384.095.206.271446.64610.601.00406.2619.558442.21

Conclusions We show that in a HER2+ BC cohort the RCB and NRI are able to identify a subgroup of patients with limited residual disease after neoadjuvant therapy with similar good prognosis as patients with pCR and therefore may not benefit from additional adjuvant therapy.

References

1 Cortazar Lancet 2014

2 FDA Regist 2014

3 Rodenhuis Ann Oncol 2010

4 Symmans JCO 2007

5 Jeruss JCO 2008

6 Mittendorf JAMA Oncol 2016

Citation Format: Steenbruggen TG, van Seijen M, Janssen LM, van Ramshorst MS, van Werkhoven E, Lips EH, Vrancken-Peeters M-JT, Horlings HM, Wesseling J, Sonke GS. Prognostic value of residual cancer burden (RCB), neo-bioscore and neoadjuvant response index (NRI) to evaluate response to neoadjuvant trastuzumab-based therapy in HER2-positive breast cancer (BC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-04.

Localization of distant metastases defines prognosis and treatment efficacy in patients with FIGO stage IV ovarian cancer

BACKGROUND

Patients with ovarian cancer who are diagnosed with Federation of Gynecology and Obstetrics (FIGO) stage IV disease are a highly heterogeneous group with possible survival differences. The FIGO staging system was therefore updated in 2014.

OBJECTIVE

To evaluate the 2014 changes to FIGO stage IV ovarian cancer on overall survival.

METHODS

We identified all patients diagnosed with FIGO stage IV disease between January 2008 and December 2015 from the Netherlands Cancer Registry. We analyzed the prognostic effect of FIGO IVa versus IVb. In addition, patients with extra-abdominal lymph node involvement as the only site of distant disease were analyzed separately. Overall survival was analyzed by Kaplan-Meier curves and multivariable Cox regression models.

RESULTS

We identified 2436 FIGO IV patients, of whom 35% were diagnosed with FIGO IVa disease. Five-year overall survival of FIGO IVa and IVb patients (including those with no or limited therapy) was 8.9% and 13.0%, respectively (p=0.51). Patients with only extra-abdominal lymph node involvement had a significant better overall survival than all other FIGO IV patients (5-year overall survival 25.9%, hazard ratio 0.77 [95% CI 0.62 to 0.95]).

CONCLUSION

Our study shows that the FIGO IV sub-classification into FIGO IVa and IVB does not provide additional prognostic information. Patients with extra-abdominal lymph node metastases as the only site of FIGO IV disease, however, have a better prognosis than all other FIGO IV patients. These results warrant a critical appraisal of the current FIGO IV sub-classification.

Selecting the optimal position of CDK4/6 inhibitors in hormone receptor-positive advanced breast cancer - the SONIA study: study protocol for a randomized controlled trial

Background

Combining cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors with endocrine therapy is an effective strategy to improve progression-free survival in hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. There is a lack of comparative data to help clinicians decide if CDK4/6 inhibitors can best be added to first- or second-line endocrine therapy. Improvement in median progression-free survival in first-line studies is larger than in second-line studies, but CDK4/6 inhibitors have not consistently shown to improve overall survival or quality of life. They do come with added toxicity and costs, and many patients have lasting disease remission on endocrine therapy alone. No subgroup has been identified to select patients who are most likely to benefit from the addition of CDK4/6 inhibition in any line of treatment. Altogether, these factors make that the optimal strategy for using CDK4/6 inhibitors in clinical practice is unknown.

Methods

The SONIA study is an investigator-initiated, multicenter, randomized phase III study in patients with HR+/HER2-negative advanced breast cancer. Patients are randomly assigned to receive either strategy A (first-line treatment with a non-steroidal aromatase inhibitor combined with CDK4/6 inhibition, followed on progression by fulvestrant) or strategy B (first-line treatment with a non-steroidal aromatase inhibitor, followed on progression by fulvestrant combined with CDK4/6 inhibition). The primary objective is to test whether strategy A is more effective than strategy B. The primary endpoint is time from randomization to second objective progression (PFS2). Secondary endpoints include overall survival, safety, quality of life, and cost-effectiveness. Five-hundred seventy-four events yield 89% power to show that strategy A has statistically significant, clinically meaningful superior PFS2 (according to ESMO-MCBS) in a log-rank test at the two-sided 95% confidence level. Given an accrual period of 42 months and an additional 18 months follow-up, inclusion of 1050 evaluable patients is required.

Discussion

This study design represents daily clinical practice, and the results will aid clinicians in deciding when adding CDK4/6 inhibitors to endocrine therapy will benefit their patients most. Additional biomarker analyses may help to optimize patient selection.

Trial registration

http://clinicaltrials.gov: NCT03425838 (8 February 2018). EudraCT-number: 2017–002334-23 (29 September 2017).

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4978-1) contains supplementary material, which is available to authorized users.

Abstract P1-13-10: Adjuvant treatment of HER2+ breast cancer: Should trastuzumab be given sequentially or concurrently with chemotherapy?

Background

Human Epidermal growth factor Receptor 2 positive (HER2+) breast cancers have a high risk of recurrence in the absence of systemic treatment. The monoclonal antibody trastuzumab in combination with chemotherapy has significantly improved survival. Randomized trials have given trastuzumab both concurrently and sequentially with chemotherapy. To date, only one study reported a comparison between concurrent and sequential trastuzumab, with a numerically but not statistically significant benefit for concurrent use.

Our aim is to evaluate whether there is a difference in survival between patients who received trastuzumab sequentially to chemotherapy compared to concurrently with chemotherapy using data from the population-based, Netherlands Cancer Registry (NCR).

Methods

All women diagnosed in the Netherlands with a HER2+, TanyNanyM0 breast tumor between 2005 and 2007 who received both chemotherapy and trastuzumab were identified from the NCR.

Kaplan Meier survival estimates and Cox regression were used to compare recurrence free survival (RFS) and overall survival (OS) by trastuzumab sequence. Hazard ratios (HR) were adjusted for grade, pathological T-stage, pathological N-stage, estrogen receptor (ER), progesterone receptor, radiotherapy, hormonal therapy and ovarian ablation.

Results

A total of 1,849 patients were identified, with a mean follow-up of 7.8 years. Of these, 1,260 received concurrent trastuzumab and 589 sequential trastuzumab. Most tumors were grade 3, node positive and ER+. During follow-up 358 RFS events occurred, 231 in the concurrently treated patients compared to 127 in sequentially treated patients. Regarding OS, 290 deaths were observed, 188 deaths in concurrently treated patients compared to 102 deaths in sequentially treated patients, respectively.

OS and RFS were similar among sequentially versus concurrently treated patients (adjusted HR 1.11; 95% CI 0.87-1.42; P=0.420 and adjusted HR 1.15; 95% CI 0.92-1.44; P=0.209, respectively).

Conclusion

We observed no significant difference in OS and RFS between patients who received sequential trastuzumab compared to patients treated concurrently. Based on our results no recommendation can be made favoring either of the two treatment sequences for the adjuvant treatment of HER2+ breast cancer patients.

Citation Format: Dackus GMHE, Jóźwiak K, Van der Wall E, Van Diest PJ, Hauptmann M, Siesling S, Sonke GS, Linn SC. Adjuvant treatment of HER2+ breast cancer: Should trastuzumab be given sequentially or concurrently with chemotherapy? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-13-10.

Abstract PD4-06: First-line ribociclib + letrozole in hormone receptor-positive, HER2-negative advanced breast cancer: Efficacy by baseline circulating tumor DNA alterations in MONALEESA-2

Background: The addition of first-line ribociclib (RIB; cyclin-dependent kinase 4/6 inhibitor) to letrozole (LET) significantly improved progression-free survival (PFS) compared with placebo (PBO) + LET in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC) in the Phase III MONALEESA-2 study. Identifying biomarkers that predict response to treatment remains a key challenge in pts with HR+ ABC. Here we analyze results from MONALEESA-2 by molecular alterations detected in circulating tumor DNA (ctDNA) at baseline, including PIK3CA mutations and other alterations considered to be important in HR+ ABC.

Methods: Postmenopausal women (N=668) with HR+, HER2– ABC who had not received any prior therapy for ABC were randomized 1:1 to RIB (600 mg/day; 3-weeks-on/1-week-off) + LET (2.5 mg/day; continuous) or PBO + LET. The primary endpoint was PFS. Biomarker analysis of the ctDNA mutation profile was an exploratory endpoint. Plasma samples for ctDNA analysis were collected at baseline and end of treatment. ctDNA was analyzed using next-generation sequencing with a targeted panel of ˜550 genes.

Results: Baseline ctDNA was successfully sequenced in 494 pts (RIB + LET: n=212; PBO + LET: n=215); 67 (14%) of 494 pts were removed from the analysis due to limited tumor DNA in circulation. 427 (86%) pts had ≥1 alteration, including 1,573 mutations, 513 short insertions/deletions, 166 amplifications, and 8 translocations. Alterations (frequency) were commonly observed in the following genes: PIK3CA (33%), TP53 (12%), ZNF703/FGFR1 (5%), and ESR1 (4%), and in genes involved in receptor tyrosine kinase (RTK) signaling (12%). RIB + LET treatment benefit was consistent in pts with wild-type (WT) and altered PIK3CA, and in pts with WT and altered TP53 (Table). RIB + LET improved PFS regardless of RTK or ZNF703/FGFR1 alterations. However, there was a weak trend for increased benefit in pts with WT vs altered RTK genes and in pts with WT vs altered ZNF703/FGFR1 genes. These results should be interpreted with caution due to the small number of pts with these alterations. There were too few ESR1 alterations for firm conclusions to be drawn.

 Events, n/NMedian PFS, months Gene(s)RIB + LETPBO + LETRIB + LETPBO + LETHazard ratio (95% confidence interval)PIK3CAWT54/14393/14229.614.70.44 (0.31–0.62)Altered40/6955/7319.212.70.53 (0.35–0.81)TP53WT72/180129/19427.614.70.44 (0.33–0.59)Altered22/3219/2110.25.50.43 (0.23–0.83)ZNF703/FGFR1WT88/202139/20524.814.60.47 (0.36–0.62)Altered6/109/1010.611.40.73 (0.23–2.29)RTKWT81/189128/18724.814.40.46 (0.35–0.61)Altered13/2320/2821.311.40.72 (0.34–1.53)

Conclusions: Consistent RIB + LET treatment benefit was observed compared with PBO + LET, irrespective of the status of baseline ctDNA biomarkers.

Citation Format: Hortobagyi GN, Stemmer S, Campone M, Sonke GS, Arteaga CL, Paluch-Shimon S, Petrakova K, Villanueva C, Nusch A, Grischke E-M, Chan A, Jakobsen E, Marschner N, Hart LL, Alba E, Ohnstand HO, Blau S, Yardley DA, Solovieff N, Su F, Germa C, Yap Y-S. First-line ribociclib + letrozole in hormone receptor-positive, HER2-negative advanced breast cancer: Efficacy by baseline circulating tumor DNA alterations in MONALEESA-2 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD4-06.

Abstract P6-12-06: Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data

Background - Fatigue is one of the most common and disabling complaints in patients with breast cancer and can effectively be reduced by physical exercise, with small to moderate effect sizes. To identify heterogeneity in responses to exercise and to further personalize exercise prescriptions, moderators of exercise effects on fatigue should be investigated. However, most randomized controlled trials (RCTs) are not adequately powered for such analyses. Therefore we conducted meta-analyses using the individual patient data of several exercise RCTs. The aim is to investigate the effect and moderators of physical exercise on cancer-related fatigue in patients with breast cancer.

Methods - Within the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) consortium, principal investigators of 34 exercise RCTs worldwide have shared their individual patient data. Twenty-two of these RCTs included patients with breast cancer with a total sample size of 3,061. Different questionnaires to assess level of fatigue were used, which was acknowledged by using z-scores in the analysis. A one-step individual patient data meta-analysis, using a linear mixed-effect model adjusted for baseline fatigue, with a random intercept on study (to account for study clustering) was undertaken to investigate effect of exercise on fatigue. The result, a between-group difference in z-scores, corresponds to a Cohen's d effect size. An interaction term was included in the model to assess potential moderators including demographic (age, marital status, education), clinical (body mass index, presence of distant metastasis), intervention-related (intervention timing, delivery mode and duration), and exercise-related (exercise type, frequency, intensity, duration) characteristics.

Results – Exercise significantly reduced fatigue reported by women with breast cancer (β= -0.15, 95% CI -0.21;-0.09). This effect did not differ significantly between patients with different demographic and clinical characteristics (p-valuesinteraction &gt;0.05). Also, neither timing (during or post-treatment) and duration of the intervention, nor exercise-related factors moderated intervention effects on fatigue. Supervised exercise had significantly larger effects on fatigue than unsupervised exercise (βdifference= -0.17, 95%CI -0.28;-0.05). Compared to the control group, supervised exercise significantly improved fatigue (β = -0.21, 95%CI = -0.28;-0.14), while unsupervised exercise did not (β = -0.04, 95%CI = -0.14;0.06).

Conclusion – Exercise significantly reduces fatigue in patients with breast cancer across subgroups formed on the basis of age, marital status, education level, body mass index, and presence of distant metastasis. The effect of exercise is significantly larger when performed under supervision. Hence, exercise, and preferably supervised exercise, represents a viable intervention for the prevention and treatment of fatigue among patients with breast cancer.

Citation Format: van Vulpen JK, Sweegers MG, Kalter J, Peeters PH, Courneya KS, Newton RU, Aaronson NK, Jacobsen PB, Steindorf K, Stuiver MM, Hayes S, Mesters I, Knoop H, Goedendorp M, Mutrie N, Thorsen L, Schmidt M, Sonke GS, Bohus M, James EL, Oldenburg HS, Velthuis MJ, Nollet F, Wenzel J, Wiskemann J, Galvão DA, Chinapaw MJ, Irwin ML, Griffith KA, van Weert E, Daley AJ, McConnachie A, Schulz K-H, Short CE, Plotnikoff RC, Potthoff K, van Beurden M, van Harten WH, Schmitz KH, Winters-Stone KM, Taaffe DR, van Mechelen W, Kersten M-J, Verdonck-de Leeuw IM, Brug J, Buffart LM, May AM. Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-06.

Optimal adjuvant endocrine treatment of ER+/HER2+ breast cancer patients by age at diagnosis: A population-based cohort study

BACKGROUND

Prior randomised controlled trials on adjuvant hormonal therapy included HER2_any patients; however, a differential effect of aromatase inhibitors (AIs) versus tamoxifen (TAM) may have been missed in ER+/HER2+ patients that comprise 7-15% of all breast cancer patients. In addition, a woman's hormonal microenvironment may influence sensitivity to TAM and AIs in the adjuvant setting, which changes during menopausal transition, a process that takes years. We studied the efficacy of AIs versus TAM in ER+/HER2+ breast cancer patients grouped by age at diagnosis as a proxy for menopausal status using treatment and outcome data from the nationwide population-based Netherlands Cancer Registry (NCR).

PATIENTS AND METHODS

All women diagnosed between 2005 and 2007 with endocrine-treated, T_anyN_anyM₀, ER+/HER2+ breast cancer were identified through the NCR (n = 1155). Patients were divided by age at diagnosis: premenopausal (≤45 years; n = 326), perimenopausal (45<years≤55; n = 304) and postmenopausal (>55 years; n = 525). A time-dependent variable, indicating whether AI or TAM was received for >50% of endocrine treatment duration, was applied to subdivide groups by predominant treatment received. Recurrence-free survival (RFS) and overall survival (OS) were assessed using Kaplan-Meier survival estimation and Cox regression. Hazard ratios (HRs) were adjusted for chemotherapy, trastuzumab, age at diagnosis, N-status, grade, pT-stage and ovarian ablation.

RESULTS

During follow-up, 237 recurrences and 182 deaths occurred. Perimenopausal women derived significant RFS and OS benefit from AI compared with TAM, HR 0.47 (95% CI 0.25-0.91; P = 0.03) and HR 0.37 (95% CI 0.18-0.79; P = 0.01), respectively, whereas premenopausal women derived no benefit from AI compared with TAM. Treatment effects differed significantly between these age groups (interaction P = 0.03 and P = 0.02, respectively). Among postmenopausal women a small but non-significant AI benefit was observed.

CONCLUSION

AI treatment, preferably without any TAM treatment, was associated with the best RFS and OS outcome in ER+/HER2+ perimenopausal breast cancer patients.

No improvement in long-term survival for epithelial ovarian cancer patients: A population-based study between 1989 and 2014 in the Netherlands

AIM

This study investigates changes in therapy and long-term survival for patients with epithelial ovarian cancer (EOC) in the Netherlands.

METHODS

All patients with EOC, including peritoneal and fallopian tube carcinoma, diagnosed in the Netherlands between 1989 and 2014 were selected from the Netherlands Cancer Registry. Changes in therapy were studied and related to overall survival (OS) using multivariable Cox regression models.

RESULTS

A total of 32,540 patients were diagnosed with EOC of whom 22,047 (68%) had advanced stage disease. In early stage, lymph node dissection as part of surgical staging procedures increased over time from 4% in 1989-1993 to 62% in 2009-2014 (P < 0.001). In advanced stage, the number of patients receiving optimal treatment with surgery and chemotherapy increased from 55% in 1989-1993 to 67% in 2009-2014 (P < 0.001). Five-year survival rates improved in both early stage (74% versus 79%) and advanced stage (16% versus 24%) as well as in all patients combined (31% versus 34%). Ten-year survival rates, however, slightly improved in early stage (62% versus 67%) and advanced stage (10% versus 13%) but remained essentially unchanged at 24% for all patients combined.

CONCLUSION

Despite intensified treatment and staging procedures, long-term survival for women with EOC has not improved in the last 25 years. The observed improvements in 5-year OS reflect a more prolonged disease control rather than better chances for cure. Furthermore, the apparent better long-term outcome, when early and advanced stage patients are analysed separately, is largely due to improved staging procedures and the ensuing stage migration. These effects disappear in a combined analysis of all patients.

Validation of the online prediction tool PREDICT v. 2.0 in the Dutch breast cancer population

BACKGROUND

PREDICT version 2.0 is increasingly used to estimate prognosis in breast cancer. This study aimed to validate this tool in specific prognostic subgroups in the Netherlands.

METHODS

All operated women with non-metastatic primary invasive breast cancer, diagnosed in 2005, were selected from the nationwide Netherlands Cancer Registry (NCR). Predicted and observed 5- and 10-year overall survival (OS) were compared for the overall cohort, separated by oestrogen receptor (ER) status, and predefined subgroups. A >5% difference was considered as clinically relevant. Discriminatory accuracy and goodness-of-fit were determined using the area under the receiver operating characteristic curve (AUC) and the Chi-squared-test.

RESULTS

We included 8834 patients. Discriminatory accuracy for 5-year OS was good (AUC 0.80). For ER-positive and ER-negative patients, AUCs were 0.79 and 0.75, respectively. Predicted 5-year OS differed from observed by -1.4% in the entire cohort, -0.7% in ER-positive and -4.9% in ER-negative patients. Five-year OS was accurately predicted in all subgroups. Discriminatory accuracy for 10-year OS was good (AUC 0.78). For ER-positive and ER-negative patients AUCs were 0.78 and 0.76, respectively. Predicted 10-year OS differed from observed by -1.0% in the entire cohort, -0.1% in ER-positive and -5.3 in ER-negative patients. Ten-year OS was overestimated (6.3%) in patients ≥75 years and underestimated (-13.%) in T3 tumours and patients treated with both endocrine therapy and chemotherapy (-6.6%).

CONCLUSIONS

PREDICT predicts OS reliably in most Dutch breast cancer patients, although results for both 5-year and 10-year OS should be interpreted carefully in ER-negative patients. Furthermore, 10-year OS should be interpreted cautiously in patients ≥75 years, T3 tumours and in patients considering endocrine therapy and chemotherapy.

Patterns and predictors of first and subsequent recurrence in women with early breast cancer

Purpose

Little is known about the occurrence, timing and prognostic factors for first and also subsequent local (LR), regional (RR) or distant (DM) breast cancer recurrence. As current follow-up is still consensus-based, more information on the patterns and predictors of subsequent recurrences can inform more personalized follow-up decisions.

Methods

Women diagnosed with stage I-III invasive breast cancer who were treated with curative intent were selected from the Netherlands Cancer Registry (N = 9342). Extended Cox regression was used to model the hazard of recurrence over ten years of follow-up for not only site-specific first, but also subsequent recurrences after LR or RR.

Results

In total, 362 patients had LR, 148 RR and 1343 DM as first recurrence. The risk of first recurrence was highest during the second year post-diagnosis (3.9%; 95% CI 3.5–4.3) with similar patterns for LR, RR and DM. Young age (<40), tumour size >2 cm, tumour grade II/III, positive lymph nodes, multifocality and no chemotherapy were prognostic factors for first recurrence. The risk of developing a second recurrence after LR or RR (N = 176) was significantly higher after RR than after LR (50 vs 29%; p < 0.001). After a second LR or RR, more than half of the women were diagnosed with a third recurrence.

Conclusions

Although the risk of subsequent recurrence is high, absolute incidence remains low. Also, almost half the second recurrences are detected in the first year after previous recurrence and more than 80% are DM. This suggests that more intensive follow-up for early detection subsequent recurrence is not likely to be (cost-)effective.

Electronic supplementary material

The online version of this article (doi:10.1007/s10549-017-4340-3) contains supplementary material, which is available to authorized users.