Vaginal changes, sexual functioning and distress of women with locally advanced cervical cancer treated in the EMBRACE vaginal morbidity substudy

OBJECTIVE

The EMBRACE-vaginal morbidity substudy prospectively evaluated physician-assessed vaginal changes and patient-reported-outcomes (PRO) on vaginal and sexual functioning problems and distress in the first 2-years after image-guided radio(chemo)therapy and brachytherapy for locally advanced cervical cancer.

METHODS

Eligible patients had stage IB1-IIIB cervical cancer with ≤5 mm vaginal involvement. Assessment of vaginal changes was graded using CTCAE. PRO were assessed using validated Quality-of-Life and sexual questionnaires. Statistical analysis included Generalized-Linear-Mixed-Models and Spearman's rho-correlation coefficients.

RESULTS

113 eligible patients were included. Mostly mild (grade 1) vaginal changes were reported over time in about 20% (range 11-37%). At 2-years, 47% was not sexually active. Approximately 50% of the sexually active women reported any vaginal and sexual functioning problems and distress over time; more substantial vaginal and sexual problems and distress were reported by up to 14%, 20% and 8%, respectively. Physician-assessed vaginal changes and PRO sexual satisfaction differed significantly (p ≤ .05) between baseline and first follow-up, without further significant changes over time. No or only small associations between physician-assessed vaginal changes and PRO vaginal functioning problems and sexual distress were found.

CONCLUSIONS

Mild vaginal changes were reported after image-guided radio(chemo)therapy and brachytherapy, potentially due to the combination of tumors with limited vaginal involvement, EMBRACE-specific treatment optimization and rehabilitation recommendations. Although vaginal and sexual functioning problems and sexual distress were frequently reported, the rate of substantial problems and distress was low. The lack of association between vaginal changes, vaginal functioning problems and sexual distress shows that sexual functioning is more complex than vaginal morbidity alone.

Flemish breast cancer screening programme: 15 years of key performance indicators (2002-2016)

Background

We examined 15 years of key performance indicators (KPIs) of the population-based mammography screening programme (PMSP) in Flanders, Belgium.

Methods

Individual screening data were linked to the national cancer registry to obtain oncological follow-up. We benchmarked crude KPI results against KPI-targets set by the European guidelines and KPI results of other national screening programmes. Temporal trends were examined by plotting age-standardised KPIs against the year of screening and estimating the Average Annual Percentage Change (AAPC).

Results

PMSP coverage increased significantly over the period of 15 years (+ 7.5% AAPC), but the increase fell to + 1.6% after invitation coverage was maximised. In 2016, PMSP coverage was at 50.0% and opportunistic coverage was at 14.1%, resulting in a total coverage by screening of 64.2%. The response to the invitations was 49.8% in 2016, without a trend. Recall rate decreased significantly (AAPC -1.5% & -5.0% in initial and subsequent regular screenings respectively) while cancer detection remained stable (AAPC 0.0%). The result was an increased positive predictive value (AAPC + 3.8%). Overall programme sensitivity was stable and was at 65.1% in 2014.

In initial screens of 2015, the proportion of DCIS, tumours stage II+, and node negative invasive cancers was 18.2, 31.2, and 61.6% respectively. In subsequent regular screens of 2015, those proportions were 14.0, 24.8, and 65.4% respectively. Trends were not significant.

Conclusion

Besides a suboptimal attendance rate, most KPIs in the Flemish PMSP meet EU benchmark targets. Nonetheless, there are several priorities for further investigation such as a critical evaluation of strategies to increase screening participation, organising a biennial radiological review of interval cancers, analysing the effect that preceding opportunistic screening has on the KPI for initial screenings, and efforts to estimate the impact on breast cancer mortality.

Abstract P1-15-04: Breast cancer recurrence and predictors for recurrence despite pathologic complete response following neoadjuvant chemotherapy

Introduction

Breast cancer patients with a high-risk tumor (for example Triple Negative Breast Cancer) who achieve a pathological complete response (pCR) following neoadjuvant chemotherapy (NACT) have a better outcome compared to patients with residual disease at surgery. This study investigated Breast Cancer Free Survival (BCFS) and predictors for distant relapse despite pCR.

Methods

Monocentric retrospective study of 243 consecutive breast cancer patients who achieved pCR (ypT0/is ypN0/N0(i+)) after treatment with NACT in UZ Leuven between 01/2000 and 08/2017. 58% had stage III breast cancer, 40% Triple Negative Breast Cancer (TNBC) and 47% HER2 pos breast cancer. BCFS was defined as any breast cancer related event (local, contra-lateral, regional, metastatic) that first appeared. Primary endpoints were frequency of BCFS and predictors for metastatic relapse: patient demographics (age, body mass index (BMI)) and tumor characteristics (TNM stage, histological type, hormonal receptor status). Secondary endpoints were breast cancer specific survival (BCSS) and overall survival (OS). Statistical analysis was performed using the Statistical Package for the Social Sciences software (SPSS, version 25). The Kaplan Meier method was used for survival analysis.

Results

Of 1167 breast cancer patients undergoing neoadjuvant treatment, 243 patients (20,8%) achieved pCR and were included. Median follow up was 57 months (range 9-252 months). 22 (9.1%) developed tumor progression; 20 (8.2%) metastatic and 2 (0.8%) contralateral. First metastatic site was the brain in 11/20 patients (55%) and 14/22 (64%) died of breast cancer. Higher clinical tumor stage at diagnosis predicted metastatic relapse (stage I-II 2.9%; stage III 12.1%). Patients with a BMI ≤25 kg/m2 had less metastatic relapse than patients with BMI >25kg/m2 (3.8% versus 12.0%), better OS (94.6% vs 88.0%) and BCSS (97.7 vs 91.7%). Neither tumor type (TNBC 8.2%; HER2-pos 8.1%; HR-pos/HER2 neg 9.3%) nor younger age < 36yrs (3.3% versus 8.9%) was prognostic for post-pCR relapse. There is a lower OS (mean 174m versus 231m, 95% CI 158-190m, median 208m) and BCSS (mean 191m versus 253m, 95% CI 182-200m) in cN1-3 versus cN0 disease at diagnosis.

Conclusion

Despite NACT-induced pCR, a small proportion (9.1%) will develop a metastatic relapse after a median follow-up of 57 months. We found that a higher stage at diagnosis and a higher BMI were prognostic for worse BCFS while age <36 y and negative hormonal receptor status were not prognostic. cN+ at diagnosis and a BMI >25 predict worse OS and BCSS.

Citation Format: Borremans K, Berteloot P, Van Nieuwenhuysen E, Han S, Hoste G, Wildiers H, Punie K, Smeets A, Nevelsteen I, Floris G, Van Ongeval C, Keupers M, Prevos R, Van Limbergen E, Menten J, Weltens C, Janssen H, Vergote I, Neven P. Breast cancer recurrence and predictors for recurrence despite pathologic complete response following neoadjuvant chemotherapy [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 P1-15-04.

Abstract P5-09-05: Hereditary breast cancer beyond BRCA: Clinical and histopathological characteristics in patients with germline CHEK2, ATM, PALB2 and TP53-mutations

Background

The introduction of multi-gene panel testing in the diagnosis of hereditary breast and ovarian cancer (HBOC) has led to an important increase in the detection of breast cancer predisposition genes other than BRCA1 and BRCA2.

Methods

All individuals who underwent HBOC-testing at our institution since the introduction of multi-gene panel testing were included (March 2016-August 2017). In this retrospective analysis, the BRCA Hereditary Cancer MASTR Plus® panel is used (Multiplicom, Belgium), with sequencing of BARD1, BRCA1, BRCA2, BRIP1, RAD51C, RAD51D, TP53, MRE11A, RAD50, NBN, FAM175A, ATM, PALB2, STK11, MEN1, PTEN, CDH1, MUTYH, CHEK2, BLM, XRCC2, EPCAM, MLH1, MSH6, PMS2, MSH2.

In breast cancer patients with a recurrent germline alteration, age and TNM stage at diagnosis, histological subtype, grade of differentiation and molecular surrogate subtype were recorded. Given the low numbers of TP53-carriers diagnosed by HBOC testing, also patients with a germline TP53-mutation diagnosed by targeted sequencing at our institution were included. Statistical analysis were performed with SPSS version 25.

Results

In 11.9 % of 2806 patients who underwent panel testing, a germline pathogenic alteration was detected. BRCA1 and BRCA2 were the most prevalent alterations, detected in respectively 3.35 and 2.92 % of patients. Germline alterations in CHEK2, ATM , PALB2 and TP53 were detected in respectively 2.5 %, 1.1 %, 0.5 % and 0.1 %. In 1 % of patients, germline alterations were retrieved that only contribute to ovarian cancer risk (BRIP, RAD51C, RAD51D). Germline DNA mismatch repair alterations were detected in 0.39 % of patients.

The median age at onset of breast cancer in patients with germline CHEK2-, ATM-, PALB2- and TP53-mutations was 47, 53, 39 and 33 years respectively. The age of breast cancer diagnosis in patients with germline TP53-alterations was significantly younger compared to patients with CHEK2-mutations (p = 0.01), ATM-mutations (p = 0.01) and PALB2-mutations (p = 0.04). In situ carcinomas were diagnosed in respectively 9 %, 11 % and 11 % of patients with CHEK2-, PALB2- and TP53-mutations. Patients with CHEK2, ATM, PALB2 and TP53-alterations were diagnosed with ≥T3-tumors in respectively 13 %, 12 %, 33 % and 22 %. Nodal status at diagnosis was negative in 40-60 % in these 4 subgroups. Upfront metastatic disease was diagnosed only in 2/43 CHEK2-carriers. More than half of the breast cancer diagnoses were luminal tumors in CHEK2-, ATM- and PALB2-carriers, while cases with germline TP53-alterations only presented with luminal cancers in 22 % in our series.

Conclusion

Almost half of the pathogenic mutations detected in HBOC-genes are alterations in genes other than BRCA1 and BRCA2. CHEK2-mutations are by far the most prevalent, followed by ATM, PALB2 and TP53.

The range of the CHEK2- and ATM-population was wider then expected at the lower-age boundary. The age of breast cancer diagnosis in patients with germline TP53-mutations was significantly younger compared to patients with CHEK2-, ATM- and PALB2-mutations. The distribution of the histological subtypes and grade of differentiation was not suggestive of a specific correlation with germline mutation status.

Citation Format: Hoste G, D'Hoore P, Legius E, Van Buggenhout G, Floris G, Wildiers H, Han SN, Van Nieuwenhuysen E, Berteloot P, Smeets A, Nevelsteen I, Weltens C, Janssen H, Van Limbergen E, Neven P, Punie K. Hereditary breast cancer beyond BRCA: Clinical and histopathological characteristics in patients with germline CHEK2, ATM, PALB2 and TP53-mutations [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 P5-09-05.

Body mass index, age at breast cancer diagnosis, and breast cancer subtype: a cross-sectional study

PURPOSE

Evidence suggests that premenopausal obesity decreases and postmenopausal obesity increases breast cancer risk. Because it is not well known whether this is subtype dependent, we studied the association between body mass index (BMI) and age at breast cancer diagnosis, or the probability of being diagnosed with a specific breast cancer phenotype, by menopausal status.

METHODS

All patients with non-metastatic operable breast cancer from the University Hospital Leuven diagnosed between January 1, 2000 and December 31, 2013 were included (n = 7020) in this cross-sectional study. Linear models and logistic regression were used for statistical analysis. Allowing correction for age-related BMI-increase, we used the age-adjusted BMI score which equals the difference between a patient's BMI score and the population-average BMI score corresponding to the patient's age category.

RESULTS

The quadratic relationship between the age-adjusted BMI and age at breast cancer diagnosis (p = 0.0207) interacted with menopausal status (p < 0.0001); increased age at breast cancer diagnosis was observed with above-average BMI scores in postmenopausal women, and with below-average BMI scores in premenopausal women. BMI was linearly related to the probabilities of Luminal B and HER2-like breast cancer phenotypes, but only in postmenopausal women. The relative changes in probabilities between both these subtypes mirrored each other.

CONCLUSION

BMI associates differently before and after menopause with age at breast cancer diagnosis and with the probability that breast cancer belongs to a certain phenotype. The opposite effect of increasing BMI on relative frequencies of Luminal B and HER2-like breast cancers suggests a common origin.

Abstract P6-09-12: A consecutive series of early breast cancers with a low estrogen receptor expression

Background: Estrogen receptor (ER) positivity is not a dichotomous biological phenomenon and within the ER positive cohort, major differences in amount and percentage of ER expression are observed. Women with tumors expressing low ER levels have worse outcome as quantitative ER (qER) expression is predictive for benefit from hormone therapy. The aim of our study was to further characterize these patients, tumors and the distant relapse free survival (D-RFS) based upon qER expression.

Patients and Methods: In this retrospective study we included women with primary operable human epidermal growth factor receptor 2 (HER2) negative breast cancers, diagnosed between January 1st 2000 and September 30th 2015 in the Multidisciplinary Breast Center of University Hospital of Leuven. ER-low tumors ((1-33% immunohistochemical (IHC)staining, Allred proportion score (2-3/5), or H-score (&lt;100/300 + &lt;33% staining)) were compared with ER-high tumors((&gt; 33% IHC staining, Allred proportion score (4-5/5), or H-score ≥ 100/300)) and triple negative (TN) tumors (Allred proportion score (0-1/5) or H-score 0% staining). PR and HER2 were scored according to ASCO/CAP guidelines. Local and adjuvant therapies were given according to the in house guidelines. The Fisher exact text was used for comparing groups on categorical variables and the Kruskal Wallis test or Mann-Whitney test were used for continuous variables. The Kaplan-Meier method was used for estimating the interval to relapse. The log rank test was used for the comparison between groups (2-sided test with 5% significance, SAS software version 9.4).

Results: A total of 5390 women were included, 115 (2 %) were ER-low, 4658 (86.5%) were ER-high and 617 (11.5%) were TN. Average follow-up was 6 years. Patients with ER-low and TN breast tumors were younger at diagnosis compared to patients with ER-high tumors (respectively 55.5y and 56.7y vs 59.3 y; p&lt;0.001). Tumor size and nodal status did not differ between the three subgroups. ER low and TN were more often grade 3 (61% and 89% vs 24%, p&lt;0.001) which led to a higher mean NPI. Adjuvant chemotherapy was more likely to be given in ER-low and TN cases (57% and 75% vs 26%, p&lt;0.001). Women with an ER-low and TN breast cancer were more often referred for BRCA1/2/CHEK-2 testing as compared to those with an ER-high tumor (respectively 21%, 22% vs 10% p&lt;0.001); a mutation was found 5 to 7 times more in the ER low and TN group (5%-7% vs 1% p&lt;0.001). Metastatic relapse was 18% in ER low (21/114 patients), 15% in TN (90/617 patients) and 6% in ER high (283/4658 patients). Using a Kaplan Meier curve, the 5 year D-RFS was 84%, 85% and 96% in ER-low, TN and ER-high cases. The 10 year D-RFS was respectively 76%, 84% and 91% (p&lt;0.001).

Conclusion: ER-low breast cancers are rare and correlate better with TN than ER-high tumors regarding demographics, tumor grade, BRCA1/2/CHEK-2 mutation risk and breast cancer outcome.Background: Estrogen receptor (ER) positivity is not a dichotomous biological phenomenon and within the ER positive cohort, major differences in amount and percentage of ER expression are observed. Women with tumors expressing low ER levels have worse outcome as quantitative ER (qER) expression is predictive for benefit from hormone therapy. The aim of our study was to further characterize these patients, tumors and the distant relapse free survival (D-RFS) based upon qER expression.

Patients and Methods: In this retrospective study we included women with primary operable human epidermal growth factor receptor 2 (HER2) negative breast cancers, diagnosed between January 1st 2000 and September 30th 2015 in the Multidisciplinary Breast Center of University Hospital of Leuven. ER-low tumors ((1-33% immunohistochemical (IHC)staining, Allred proportion score (2-3/5), or H-score (&lt;100/300 + &lt;33% staining)) were compared with ER-high tumors((&gt; 33% IHC staining, Allred proportion score (4-5/5), or H-score ≥ 100/300)) and triple negative (TN) tumors (Allred proportion score (0-1/5) or H-score 0% staining). PR and HER2 were scored according to ASCO/CAP guidelines. Local and adjuvant therapies were given according to the in house guidelines. The Fisher exact text was used for comparing groups on categorical variables and the Kruskal Wallis test or Mann-Whitney test were used for continuous variables. The Kaplan-Meier method was used for estimating the interval to relapse. The log rank test was used for the comparison between groups (2-sided test with 5% significance, SAS software version 9.4).

Results: A total of 5390 women were included, 115 (2 %) were ER-low, 4658 (86.5%) were ER-high and 617 (11.5%) were TN. Average follow-up was 6 years. Patients with ER-low and TN breast tumors were younger at diagnosis compared to patients with ER-high tumors (respectively 55.5y and 56.7y vs 59.3 y; p&lt;0.001). Tumor size and nodal status did not differ between the three subgroups. ER low and TN were more often grade 3 (61% and 89% vs 24%, p&lt;0.001) which led to a higher mean NPI. Adjuvant chemotherapy was more likely to be given in ER-low and TN cases (57% and 75% vs 26%, p&lt;0.001). Women with an ER-low and TN breast cancer were more often referred for BRCA1/2/CHEK-2 testing as compared to those with an ER-high tumor (respectively 21%, 22% vs 10% p&lt;0.001); a mutation was found 5 to 7 times more in the ER low and TN group (5%-7% vs 1% p&lt;0.001). Metastatic relapse was 18% in ER low (21/114 patients), 15% in TN (90/617 patients) and 6% in ER high (283/4658 patients). Using a Kaplan Meier curve, the 5 year D-RFS was 84%, 85% and 96% in ER-low, TN and ER-high cases. The 10 year D-RFS was respectively 76%, 84% and 91% (p&lt;0.001).

Conclusion: ER-low breast cancers are rare and correlate better with TN than ER-high tumors regarding demographics, tumor grade, BRCA1/2/CHEK-2 mutation risk and breast cancer outcome.

Citation Format: Paredis D, Wildiers H, Vergote I, Smeets A, Van Limbergen E, Remmerie C, Laenen A, Jongen L, Floris G, Neven P. A consecutive series of early breast cancers with a low estrogen receptor expression [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-12.

Abstract P6-09-32: The association of breast cancer subtype and breast cancer survival with parity and time since last birth

Background: Pregnancy affects breast cancer risk but it's influence on breast cancer subtype and prognosis remains controversial. We studied the effect of parity and time since last birth on breast cancer subtype and outcome in women aged ≤50 years at diagnosis.

Patients and Methods: A retrospective multivariate cohort study including all premenopausal women aged ≤50 years (N=1306) at diagnosis and primarily treated with surgery (N=1176) or neo-adjuvant chemotherapy (N=130) at University Hospitals Leuven (Jan. 2000 – Dec. 2009); local and systemic therapies were consistent with guidelines when treated. Tumor subtypes were defined by tumor grade and receptor expression for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) amplification; ER+PR+/-HER-2- cases were Luminal A- like if grade 1-2 and Luminal B like if grade 3; HER-2+ cases were Luminal HER-2 if ER+ and HER-2 like if ER-; triple negative breast cancer (TNBC) were ER-PR-HER-2-. Outcome endpoints were breast cancer subtype, disease free (DFS) and distant disease free survival (DDFS) by parity and in parous women comparing short (&lt;5 years) versus long (≥5 years) time since last birth. Statistics used were Cox proportional hazard model. Results were corrected for age at diagnosis, tumor size, lymph node status and tumor subtype.

Results: Breast cancer subtypes didn't differ between nulliparous and parous women but subtypes differed significantly in parous women by time interval since last birth (p&lt;0.001). Breast cancers within 5 years of last birth were proportionally more likely TNBC and HER-2 like compared to Luminal A (p=0.026 and p=0.003 respectively) than breast cancers ≥5 years after last birth even when corrected for age at diagnosis. After a mean follow-up period of 10 years, parous women had a better DFS compared to nulliparous women (DFS: HR 0.754; CI 0.593-0.959; p=0.021) but after correction for known prognostic factors, only a trend remained (HR 0.783; CI 0.611-1.004; p=0.054). In parous women, those with a longer time interval since last birth had a better DFS than women with a recent pregnancy (HR 0.965; CI 0.948-0.982; p&lt;0.001). However, after correction for known prognostic factors, this association was completely attenuated (HR 0.997; CI 0.972-1.023; p=0.828). Comparable results were seen for DDFS.

Conclusion: After correction for age at diagnosis, parity does not but recent birth does affect breast cancer subtype. Such tumors are proportionally more likely ER-negative namely TNBC and HER-2 like. We observed a trend for better DFS for parous women. The prognostic value of time since last birth is mostly due to tumor characteristics and age at time of diagnosis.

Citation Format: De Mulder H, Laenen A, Wildiers H, Punie K, Poppe A, Remmerie C, Nevelsteen I, Smeets A, Van Nieuwenhuysen E, Van Limbergen E, Floris G, Vergote I, Neven P. The association of breast cancer subtype and breast cancer survival with parity and time since last birth [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-32.

Omitting radiation therapy in women with triple-negative breast cancer leads to worse breast cancer-specific survival

PURPOSE

To examine locoregional recurrence (LRR) and breast cancer-specific survival (BCSS) after breast-conserving therapy (BCT) or mastectomy (ME) with or without radiation therapy (RT) in triple-negative breast cancer (TNBC).

MATERIAL & METHODS

We identified non-metastatic TNBC cases from a single institution database. BCT, ME with RT (ME + RT) and ME only were compared with respect to LRR and BCSS. Cox regression models were used to analyze the association between prognostic factors and outcome.

RESULTS

439 patients fulfilled the inclusion criteria. Median follow-up was 10.2 years (interquartile range 7.9; 12.4 years). Patients in the BCT (n = 239), ME + RT (n = 116) and ME only (n = 84) group differed with respect to age, pT, pN, lymphovascular invasion, lymph node dissection and chemotherapy administration. Ten-year LRR rates were seven percent, three percent and eight percent for the BCT, ME + RT and ME only group, respectively. pN was associated with LRR. In multivariable analysis LRR were significantly lower in the ME + RT group compared to the BCT and the ME only group (p 0.037 and 0.020, respectively). Ten year BCSS was 87%, 84% and 75% for the BCT, ME + RT and ME only group, respectively. pT, pN, lymph node dissection, lymphovascular invasion and the administration of chemotherapy were associated with BCSS. In multivariable analysis BCSS was significantly lower in the ME only group compared to the BCT group and the ME + RT group (p 0.047 and 0.003, respectively).

CONCLUSION

TNBC patients treated with ME without adjuvant RT showed significant lower BCSS compared to patients treated with BCT or ME + RT and significant more LRR compared to ME + RT when corrected for known clinicopathological prognostic factors.

First results of the Flemish colorectal cancer screening program : start-up- period late 2013

BACKGROUND AND AIMS

Investigation of the first participation rate and follow-up results of the Flemish colorectal cancer screening program.

PATIENTS AND METHODS

In 2013 five age cohorts with an even age between 66 and 74 year old (n=243 335) were invited by mail to return a completed iFOBT. Participants who tested positive (≥75ng/ml) were referred to a follow-up colonoscopy.

RESULTS

Participation rate was 48.4% (n=117 774). Overall positivity rate was 10.1%, and 78.1% of those tested positive underwent a colonoscopy. The positive predictive value of colonoscopy for CRC was 8.2%, for advanced adenoma 16.9% and for non-advanced adenoma 36.5%.

CONCLUSIONS

Based on the EU-guidelines 35% was expected as participation for a first screening round, thus a participation rate of 48.4% is more than acceptable for a first screening year. The high positivity rate can partly be explained by including only the older ages in the start-up-period and by the first year of mass screening in Flanders. (Acta gastroenterol. belg., 2016, 79, 421-428).

Abstract P6-09-12: Breast cancer characteristics and the levonorgestrel intrauterine device. A monocentric retrospective study

OBJECTIVE: The levonorgestrel-intrauterine device (LNG-IUD) is a widely used contraceptive method. It is not clear if LNG-IUD users are more likely to develop breast cancer. Breast cancer growth through the estrogen and/or the human epidermal growth factor receptor 2 (HER2) pathway could be influenced by a continuous low systemic dose of levonorgestrel. In this study, we compare breast cancer characteristics and the receptor expression of estrogen (ER), progesterone (PR) and HER2 in women with and without a LNG- IUD at the time of diagnosis.

METHODS: In this retrospective, observational study, we included 2599 consecutive breast cancer patients who were younger than 55 years at diagnosis and treated between 2000 and 2014 in the University Hospitals Leuven for a primary invasive, non-metastatic tumor. The non LNG-IUD group was matched by age and parity at diagnosis. ER, PR and HER2 status were reported according to ASCO/CAP guidelines. The Chi-square test was used to compare receptor status between groups. All tests were two-sided, and a 5% significance level was assumed. An additional analysis was performed to detect the occurrence of HER 2 expression with or without intake of oral contraception by diagnosis in the control group.

RESULTS: 366 LNG-IUD users and 2233 women without a LNG-IUD were included. Compared to the control group, the LNG-IUD users had a lower Nottingham prognostic index (4.2 vs 4.4; p=0.048), more PR expression (79.2% vs 73.4%; p=0.021) but less HER2 expression (11.6% vs 17.2%; p=0.009). A significant higher rate of ER+PR+HER2- was observed in the LNG-IUD group (63.26 % vs 73.46%; p&lt;0.001). These differences in receptor expression were mainly observed in the age group 45-49 years at diagnosis. Additionally, a trend of more HER2 positivity associated with oral contraceptive use was noticed in the control group.

CONCLUSION: We found in a breast cancer population, matched for age and parity, significant differences in the PR and HER2 expression according to use of LNG-IUD at time of diagnosis. ER positive, PR positive and HER2 negative breast cancers are more frequently seen in LNG-IUD users. There is a trend of less HER 2 positivity in LNG-IUD users and it is more common seen in oral contraception users.

Citation Format: Borowski E, Poppe A, Laenen A, Remmerie C, Van Asten K, Nevelsteen I, Smeets A, Weltens C, Peeters S, Leunen K, Berteloot P, Amant F, Vergote I, Van Limbergen E, Christiaens M-R, Wildiers H, Floris G, Poppe W, Neven P. Breast cancer characteristics and the levonorgestrel intrauterine device. A monocentric retrospective study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-09-12.

Abstract P6-09-11: Independent prognostic value of age depends on breast cancer subtype

Background: Young women present more often with aggressive breast cancer phenotypes and have worse prognosis. It remains controversial whether age is an independent prognostic factor in early stage breast cancer. Arbitrarily chosen age cut-off values have been proposed in different studies. Furthermore, few studies have examined the impact of breast cancer subtypes on the prognostic value of age. This abstract represents an update of a prior analysis (San Antonio Breast Cancer Symposium, December 4-8 2012, P06-07-29).

Methods: We included all primary operable female breast cancer patients from our prospectively managed database in UZ Leuven, Belgium. We assessed the effect of age on locoregional free interval (LRRFI), distant metastasis interval (DMFI) and breast cancer specific survival (BCSS). In univariate analysis, using Cox regression models, we determined the best categorization of age at diagnosis into two or three age groups by considering all possible combinations of cut-off values. Best categorization was obtained with three age groups. We further determined, using multivariate analysis (correcting for phenotype, tumor size, nodal status, adjuvant chemo -, hormone – and radiotherapy, type of surgery and procedure of axillary staging), whether age at diagnosis remains an independent predictor of outcome (LRRFI, DMFI and BCSS). We further explored whether age at diagnosis is an independent predictor of event risk (LRRFI, DMFI and BCSS) in different breast cancer subtypes. Luminal A-like (grade I or II, ER and/or PR positive, HER 2 positive), Luminal B-like (idem but grade III), Luminal HER 2 like (ER and/or PR positive, HER 2 positive), HER 2 like (ER/PR negative, HER 2 positive), triple negative (ER/PR negative, HER 2 negative).

Results: We included 4180 patients with a mean/median age of 58/57 year and with a median follow up of 8.9 year. Multivariate analysis confirmed age as an independent prognostic variable for LRRFI, DMFI and BCSS.

Results multivariable analysis with age in 3 groups (HR (95% CI) P-VALUE) LRRFIDMFIBCSSYoungest versus middle1.61 (1.18-2.18) 0.00251.54 (1.23-1.93) 0.00021.72 (1.26-2.36) 0.0007Youngest versus oldest3.45 (1.85-6.45) 0.00011.25 (0.89-1.77) 0.19821.31 (0.85-2.02) 0.2220Middle versus oldest2.15 (1.22-3.79) 0.00820.81 (0.61-1.09) 0,17060.76 (0.55-1.06) 0.1014

We found optimal cut-off values for LRRFI at 44y and 72y, for DMFI at 47y and 71y and for BCSS at 41y and 70y.

In an exploratory analysis, with age as continuous variable, by subtype we found a significant independent association between age and LRRFI (P=0.0169), DMFI (P=0.0344) in luminal A-like, LRRFI (P=0.0022) in luminal B-like and DMFI (P=0.0010) and BCSS (P=0.0053) in triple negative breast cancer. No significant associations were found in luminal HER2 and HER2 like breast cancers.

Conclusion:

This study has shown that young age is an independent prognostic factor for LRRFI, DMFI and BCSS after correction for the most important clinical prognostic factors. The prognostic effect is most important in luminal A and triple negative subtypes. Additional analyses for subtypes with age as a categorical variable will be performed and optimal cut off values will be defined.

Citation Format: Poppe A, Brouckaert O, Laenen A, Soubry A, Remmerie C, Floris G, Leunen K, Berteloot P, Amant F, Vergote I, Nevelsteen I, Smeets A, Christiaens M-R, Weltens C, Peeters S, Van Limbergen E, Wildiers H, Neven P. Independent prognostic value of age depends on breast cancer subtype. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-09-11.

Abstract P6-10-06: The impact of body mass index on age at breast cancer diagnosis and breast cancer phenotype

Background

Evidence suggests that premenopausal obesity decreases and postmenopausal obesity increases breast cancer risk. While it has been hypothesized that carcinogenesis may be accelerated by a disrupted metabolic homeostasis in obese women, it is unclear why this dual relationship is observed. We here study whether body mass index (BMI) affects (a) age at breast cancer diagnosis and (b) the probability of being diagnosed with a specific breast cancer phenotype, taking menopausal status into account.

Patients and methods

All patients with non-metastatic operable breast cancer from UZ Leuven diagnosed between January 1, 2000 and December 31, 2013 were included (n=7020). Luminal A like (= grade 1 or 2, ER and/or PR positive, HER2 negative), Luminal B like (= grade 3 ER and/or PR positive, HER2 negative), Luminal HER2 like (ER and/or PR positive, HER2 positive), HER2 like (ER and PR negative, HER2 positive) and triple negative breast cancer (TNBC = ER and PR and HER2 negative). For statistical analysis, linear models and logistic regression were used to study respectively the association between BMI and age at diagnosis and BMI and breast cancer phenotype by menopausal status.

Results

There was a quadratic relationship between BMI and age at breast cancer diagnosis studying the overall population (p&lt;0.0001). A 5kg/m2 increase in BMI was associated with the following increases in age at diagnosis: +1.8y (95% CI 1.4-2.3y) at BMI=18, +1.2y (95% CI 0.95-1.5y) at BMI=23 and +0.6y (95% CI 0.4-0.9y) at BMI=28 (corrected for menopause). This relationship was independent of the menopausal status, ER or HER2 status, histology and breast cancer phenotype.

We observed a linear relationship between BMI and the probability of being diagnosed with Luminal B like, Luminal HER2 like and HER2 like breast cancer (table 1). This linear relationship interacts with menopausal status for Luminal B like and HER2 like breast cancers (table 1).

Table 1: Probability of being diagnosed with a certain breast cancer phenotype by BMI (linear model) and the impact of menopausal status.Effect of BMI on the probabilityLinear modelof being diagnosed withp-valueeffectLuminal A like0.4430n/aLuminal B like0.0276BMI +5kg/m2 OR 1.07 (95% CI 1.01-1.14)Luminal HER2 like0.0367BMI +5kg/m2 OR 0.91 (95% CI 0.83-1.00)HER2 like0.0219BMI +5kg/m2 OR 0.88 (95% CI 0.78-0.98)TNBC0.5454n/aInteraction with menopausal statusp-valueeffectLuminal A0,2204n/aLuminal B0,0487Premenopausal OR 0,996 (CI 0,974-1,019), p=0,7449; Postmenopausal OR 1,023 (CI 1,008-1,038), p=0.0023Luminal HER20,2571n/aHER2 like0,0031Premenopausal OR 1,020 (CI 0,983-1,059), p=0,2923; Postmenopausal OR 0,947 (CI 0,919-0,976), p=0.0004TNBC0,1638n/a

Conclusion

We could not confirm the hypothesis that increasing BMI decreases (increases) age at diagnosis in postmenopausal (premenopausal) women. Obesity does affect the probability of being diagnosed with certain breast cancer phenotypes, but for certain breast cancer phenotypes an interaction with menopause was observed. We presume a potential biological link through BMI between Luminal B and HER2 like breast cancer that needs further exploration.

Citation Format: Brouckaert O, Poppe A, Laenen A, Floris G, Leunen K, Berteloot P, Amant F, Vergote I, Smeets A, Weltens C, Peeters S, Van Limbergen E, Wildiers H, Christiaens M-R, Neven P. The impact of body mass index on age at breast cancer diagnosis and breast cancer phenotype. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-10-06.

Quantifying independent risk factors for failing to rescreen in a breast cancer screening program in Flanders, Belgium

BACKGROUND

Mammographic screening may reduce breast cancer mortality by about 20%, provided participation is high and women screen regularly. We quantified independent risk factors for failing to rescreen and built a model to predict how rescreening rates change if these risk factors would be modified.

METHODS

Multivariate analysis was used to analyze data from a prospective study which included a self-administered questionnaire and rescreening status 30months after a t0 mammogram, using a random sample of women 50-67years (Belgium 2010-2013).

RESULTS

A false positive result at the most recent past mammogram (Odds Ratio=5.0, 95% Confidence Interval 3.6-6.8), an interval until new invitation greater than 25months (Odds Ratio=4.8 for >29months, 95% Confidence Interval 2.9-8.1), waiting times in the mammography unit >1h (Odds Ratio=2.1, 95% Confidence Interval 1.2-3.7) and difficulties in reaching the unit (Odds Ratio=2.5, 95% Confidence Interval 1.4-4.4) were the strongest independent predictors for failing to rescreen. The area under the curve of the receiver operating characteristic analysis was 0.705 for the model development stage and 0.717 for the validation stage and goodness-of-fit was good.

CONCLUSIONS

Maintaining an invitation cycle of maximum 25months, limiting waiting time in the mammography unit and lowering the number of false positives could increase breast cancer screening compliance.

Evaluation of the quality of the management of cancer of the corpus uteri--selection of relevant quality indicators and implementation in Belgium

OBJECTIVE

Describe the methodology and selection of quality indicators (QI) to be implemented in the EFFECT (EFFectiveness of Endometrial Cancer Treatment) project. EFFECT aims to monitor the variability in Quality of Care (QoC) of uterine cancer in Belgium, to compare the effectiveness of different treatment strategies to improve the QoC and to check the internal validity of the QI to validate the impact of process indicators on outcome.

METHODS

A QI list was retrieved from literature, recent guidelines and QI databases. The Belgian Healthcare Knowledge Center methodology was used for the selection process and involved an expert's panel rating the QI on 4 criteria. The resulting scores and further discussion resulted in a final QI list. An online EFFECT module was developed by the Belgian Cancer Registry including the list of variables required for measuring the QI. Three test phases were performed to evaluate the relevance, feasibility and understanding of the variables and to test the compatibility of the dataset.

RESULTS

138 QI were considered for further discussion and 82 QI were eligible for rating. Based on the rating scores and consensus among the expert's panel, 41 QI were considered measurable and relevant. Testing of the data collection enabled optimization of the content and the user-friendliness of the dataset and online module.

CONCLUSIONS

This first Belgian initiative for monitoring the QoC of uterine cancer indicates that the previously used QI selection methodology is reproducible for uterine cancer. The QI list could be applied by other research groups for comparison.

Pre-operative irradiation for retroperitoneal liposarcoma: results of a pilot study

PURPOSE

The aim of this study was to evaluate toxicity and benefit of an original method of preoperative irradiation combined with adequate surgery in the treatment of retroperitoneal liposarcoma. Instead of irradiating the whole tumor volume, 50Gy in 25 fractions was delivered to the posterior part of the tumor and the contact zone with the postero-lateral abdominal wall only.

METHODS

Between mid-2000 and end of 2011, 29 patients were included in this study, 22 with a primary tumor, 7 with a first local recurrence. The results obtained were compared with a well-matched control group operated on by the same surgeon during the same period.

RESULTS

This therapy was well tolerated by all included patients and no difference in toxicity was found between pilot and control group. With a median follow-up of 84 months the oncological results were similar in both groups with a 5 y disease specific survival of 79 and 81% (p: 0.61). However a very significant difference was found according to histotype: five year disease specific survival was 84% (CI 66-93) for the well- differentiated and only 35% (CI 20-51) for the dedifferentiated liposarcoma (p < 0.0001).

CONCLUSIONS

This form of combined treatment is well tolerated but superiority could not be demonstrated. Our experience clarifies some of the difficulties facing a randomized clinical trial on this topic.

Breast cancer phenotype, nodal status and palpability may be useful in the detection of overdiagnosed screening-detected breast cancers

BACKGROUND

Breast cancer remains the leading cause of female cancer death despite improvements in treatment and screening. Screening is often criticized for leading to overdiagnosis and overtreatment. However, few have attempted to identify overdiagnosed cases.

PATIENTS AND METHODS

A large, consecutive series of patients treated for primary operable, screening-detected, breast cancer (n = 1610). Details from pathology and clinical reports, treatment and follow-up were available from our prospectively managed database. Univariate and multivariate Cox proportional models were used to study the prognostic variables in screening-detected breast cancers for distant metastatic and breast cancer-specific survival.

RESULTS

We included 1610 patients. The mean/median follow-up was 6.0/6.0 years. Univariate analysis: tumor size, palpability, breast cancer phenotype and nodal status were predictors of distant metastasis and breast cancer-specific death. Multivariate analysis: palpability, breast cancer phenotype and nodal status remained independent prognostic variables. Palpability differed by breast cancer phenotype.

CONCLUSION

Screening-detected breast cancer is associated with excellent outcome. Palpability, nodal status and breast cancer phenotype are independent prognostic variables that may select patients at increased risk for distant metastatic relapse and breast cancer-specific death. Overdiagnosed cases reside most likely in the nonpalpable node negative subgroup with a Luminal A phenotype.

The prognostic role of preoperative and (early) postoperatively change in CA15.3 serum levels in a single hospital cohort of primary operable breast cancers

Measuring CA15.3 serum levels in the early breast cancer setting is not recommended by current ASCO guidelines. In this large single center study, we assess the prognostic value of preoperative (n = 3746), postoperative (n = 4049) and change in (n = 3252) CA15.3, also across different breast cancer phenotypes. Preoperative, postoperative and change in CA15.3 were all significant (p = 0.0348, p < 0.0001, p < 0.0001 respectively in multivariate analysis) predictors of distant metastasis free survival. For breast cancer specific survival, only postoperative and change in CA15.3 were significant predictors (p < 0.0001 both). Multivariate prognostic models did not improve by incorporating information on preoperative CA15.3, but did improve when introducing information on postoperative CA15.3 for distant metastasis (p = 0.0365) and on change in CA15.3 for breast cancer specific survival (p = 0.0291). Change in CA15.3 impacts on prognosis (distant metastasis) differently in different breast cancer phenotypes. A decrease in CA15.3 may be informative of improved prognosis in basal like and HER2 like breast cancer.

Abstract P4-15-01: Second conservative treatment for ipsilateral breast tumor recurrence: GEC-ESTRO Breast WG study

For ipsilateral breast cancer tumor (IBTR), radical mastectomy represents the treatment option frequently proposed to the patient. A second conservative treatment (SCT) has been proposed using either lumpectomy alone or associated with a second irradiation of the tumor bed. However, in both clinical situations, the proof level of such therapeutic approaches remains low, based on cased-series or retrospective studies.

To analyze the clinical outcome of a SCT using lumpectomy and multicatheter interstitial brachytherapy (MIB) for IBTR, the GEC-ESTRO Breast Working Group retrospectively analyzed the results of 217 patients (pts) with an IBTR treated between 09/00 and 09/10 in 8 European institutions by lumpectomy and MIB (low - LDR, pulse - PDR, or high-dose rate - HDR). Survival rates without 2nd local (2nd LR) and metastatic recurrence, disease free survival (DFS) and specific and overall survivals were analyzed as well as late effects and cosmetic results. Dosimetric data were reported according to the dose rate used. Univariate and multivariate analysis were performed to find local, metastatic and/or DFS progression prognostic factors.

With a median follow-up of 14.5 years [3.5–38.2] and 3.9 years [1.1–10.3] from primary tumor and IBTR respectively and a median time interval of 9.4 years [1.1–35.4] between primary and IBTR, 20.7% of the local recurrence were observed at distance from the primary tumor. Median tumor sizes were 15 mm [1–60] and 11 mm [1–40] for the primary and IBTR respectively. Thirty-nine percent of the patient underwent an axillary lymph node dissection at the time of IBTR. Median radiotherapy dose for the primary was 56 Gy [30–69.6]. Positive hormonal receptor status for IBCR was 72.8% while 65% and 19.8% received hormonal and chemotherapy respectively as adjuvant therapy for the IBTR. Five and 10-year actuarial 2nd LR rates were 5.6% [1.5–9.5] and 7.2% [2.1–12.1] respectively. Five and 10-year actuarial metastatic recurrence rates were 9.6% [5.7–15.2] and 19.1% [7.8–28.3] respectively. Five and 10-year actuarial DFS rates were 84.6% [78.9–90.6] and 77.2% [67.5–88.3] respectively. Five and 10-year actuarial overall/specific survival (OS) rates were 88.7% [83.1–94.8] and 76.4% [66.9–87.3] respectively. 141 pts developed 193 complications. Fibrosis was the most frequent complication with 11% of G3-4 complications. Cosmetic result was jugged as excellent/good in 85%. Focusing on multivariate analysis, prognostic factors for 2nd LR, metastatic recurrence and DFS are reported.

Abstract P6-07-19: Prognostic relevance of PR and detection mode in Luminal Her-2 negative breast cancer

Introduction: Although known to hold prognostic value, PR status is not used to discriminate luminal A from luminal B HER2 negative breast cancers. We will here assess whether PR (and also detection mode) is an independent prognostic variable in luminal HER2 negative breast cancer and whether the prognostic value of PR is grade dependent.

Patients and methods: Primary operable breast cancer patients diagnosed between 1/1/2000 and 31/12/2009 treated in UZ Leuven were retrieved from the prospectively managed database (n = 4318). Her-2 status was missing in 93 and ER/PR in 2 patients. Of the remaining patients, 3330 were luminal (ER and/or PR positive) HER2 negative (full cohort details: Brouckaert O., et al. Ann Oncol. 2012 Apr 6). Missing values were observed in 137 patients (4.1%), and these were imputed using ‘multivariate imputation by chained equations’. A competing risks proportional hazards model was used for multivariable analysis (includes age, size, grade, screening, palpability, nodal status, histology, type of surgery, radiotherapy, endocrine and chemotherapy) of distant metastasis free interval (DMFI) and breast cancer specific survival (BCSS). We used a predefined set of predictors, investigated non-linearity of the predictor effects, checked the proportional hazards assumption, and tested for interactions with grade.

Results: Median follow-up was 76 months and 5-year survival probability 93%. PR is an independent prognostic variable but this is grade dependent for DMFI, but not for BCSS (interaction p = 0.15), although PR positivity was mainly protective for grade 3 breast cancers again (table 1). Palpability is a strong prognostic variable for DMFI and BCSS and was strongly correlated with screen detection (yes/no) and here, we found no evidence of grade dependency.