correlated to overall survival after logistic regression. On Cox regression analysis, the hazard ratio was significantly higher for R>2 cm in all sub-groups (HR=2.7, 95% CI-1.23 – 6.07, p<0.05).

Introduction/Background The treatment of older women with ovarian cancer is challenging due to increased pre-existing co-morbidities and frailty, often leading to less radical treatment than the standard of care. Older women are frequently excluded from clinical trials. Recent studies such as the EWOC-1 study focused on elderly women with ovarian cancer suggest worse outcomes associated with less radical treatment approaches. Methodology Women diagnosed with ovarian cancer ≥65 years old referred to oncology services at three Irish University Hospitals between 2015 and 2021 were included. We evaluated patterns regarding surgery and chemotherapy sequencing, choice of agent and completion rates, according to age group. Survival outcomes were examined by Kaplan Meier analysis. The study received ethical approval. Results 190 patients were included in this study. 65.26% (124) of these women had an ECOG performance status of 0–1 at diagnosis. 129 patients (67.89%) had (FIGO) stage III or stage IV disease at diagnosis. 55% of all stage III/IV patients had optimal debulking surgery. 37% of stage III/IV patients received neoadjuvant chemotherapy followed by surgery and 27% had surgery followed by chemotherapy. Women in the ≥75 group were more likely to receive single agent carboplatin (38%), compared to women aged 65–74 years (30%). Median overall survival for all stage III/IV patients who received SA Carboplatin was 15 months versus 22 months for Carboplatin and Paclitaxel groups. BRCA testing was sub-optimal in this age group at 28% of all patients although routine BRCA testing has only been available in Ireland since 2019. Conclusion Elderly ovarian cancer patients, particularly those ≥75 years, may receive less radical treatment approaches than standard of care. Our cohort suggests improved survival with carboplatin/paclitaxel, although our cohort is too small to draw significant conclusions. Rates of BRCA testing were low. Geriatric oncology assessments should be incorporated into treatment decisions.

Pregnancy-associated breast cancer (PABC) is defined as breast cancer diagnosed during the gestational period (gp-PABC) or in the first postpartum year (pp-PABC). Despite its infrequent occurrence, the incidence of PABC appears to be rising due to the increasing propensity for women to delay childbirth. We have established the first retrospective registry study of PABC in Ireland to examine specific clinicopathological characteristics, treatments, and maternal and foetal outcomes. This was a national, multi-site, retrospective observational study, including PABC patients treated in 12 oncology institutions from August 2001 to January 2020. Data extracted included information on patient demographics, tumour biology, staging, treatments, and maternal/foetal outcomes. Survival data for an age-matched breast cancer population over a similar time period was obtained from the National Cancer Registry of Ireland (NCRI). Standard biostatistical methods were used for analyses. We identified 155 patients—71 (46%) were gp-PABC and 84 (54%) were pp-PABC. The median age was 36 years. Forty-four patients (28%) presented with Stage III disease and 25 (16%) had metastatic disease at diagnosis. High rates of triple-negative (25%) and HER2+ (30%) breast cancer were observed. We observed an inferior 5-year overall survival (OS) rate in our PABC cohort compared to an age-matched breast cancer population in both Stage I–III (77.6% vs 90.9%) and Stage IV disease (18% vs 38.3%). There was a low rate (3%) of foetal complications. PABC patients may have poorer survival outcomes. Further prospective data are needed to optimise management of these patients.

Abstract Background Pregnancy associated breast cancer (PABC) is defined as breast cancer (BC) diagnosed during the gestational period (GP) or in the first year postpartum (PP). Despite its infrequent occurrence, the incidence of PABC appears to be rising due to the increasing propensity for women to delay childbirth. We have established the first combined prospective and retrospective registry study of PABC in Ireland to examine specific clinicopathological characteristics, treatments and maternal outcomes. We present the retrospective findings to date. Methods We performed a retrospective multicentre observational study of patients (pts) with PABC treated in the eight Irish cancer centres from August 2001 to March 2017. Data extracted included information on pt demographics, tumour biology, staging, treatment administered and maternal outcomes. Standard biostatistical methods were used for analysis. Results 111 PABC patients were identified. Sixty pts (54%) were diagnosed during the GP and 51 (46%) within 1 year PP. Median age at diagnosis was 36 years (yrs). Table 1 illustrates baseline characteristics. Two thirds of pts were node positive and a similar proportion had grade 3 pathology. Seventy pts (63%) were estrogen receptor (ER) positive, 36 (32%) HER2 positive, 25 (22%) triple negative. Twenty-two pts (20%) were metastatic at presentation. Seven pts (6%) had a known BRCA 1/2 mutation. The median OS (overall survival) and DFS (disease free survival) for the entire cohort was 107.4 and 94.2 months respectively (resp). There was no survival difference between those diagnosed during the GP versus PP. 5 yr DFS and OS was 68.6% and 69.2% resp. This compares unfavourably to results reported by the National Cancer Registry of Ireland in a similar age-matched BC population between 2000-2012 where the 5 yr OS was 86.5%. Variables in our study associated with poorer outcomes included younger age, tumour size, node positivity and lack of estrogen expression. Baseline characteristics PABC patients (n=11) %(n)Diagnosed in GP (n=60) %(n)Diagnosed 1yr PP (n=51) %(n)p valueDemographic Age at diagnosis3636(25-49)36(21-44)0.31Stage I-II54(60)55(33)53(27)0.85III23(26)23(14)23(12)1IV20(22)18(11)22(11)0.81Unknown3(3)3(2)2(1)1Pathology Grade 366(74)70(42)63(32)0.43Node positive66(73)68(41)63(32)0.55ER+/HER2-41(45)38(23)43(22)0.69ER+/HER2+23(25)28(17)16(8)0.17ER-/HER2+14(16)17(10)12(6)0.59Triple negative22(25)17(10)29(15)0.11Surgery Breast conservation23(26)25(15)21(11)0.82Mastectomy56(63)57(34)59(30)0.84Adjuavnt/Neoadjuvant treatment Chemotherapy73(81)77(46)69(35)0.39Anthracycline68(55)78(36)54(19)0.03Taxane89(72)93(43)83(29)0.16Anti HER2 agent21(23)18(11)24(12)0.63Endocrine therapy64(52)63(29)66(23)0.84Radiotherapy79(64)74(34)86(30)0.85Relapse in Stage I-III Local relapse15(13)12(6)18(7)0.55Distant relapse24(21)22(11)25(10)0.80 Conclusions PABC patients may have a poorer outcome. Our study reported higher rates of triple negative and HER2 positive breast cancer which are associated with more aggressive biology. Prospective evaluation of clinicopathological features, pharmacokinetics of treatments selected and maternal and fetal outcomes is imperative in this distinct pt group. Citation Format: Prior L, Teo M, Greally M, Ward C, O'Leary C, Aslam R, Darwish W, Ahmed N, Watson G, Kelly D, Kiely L, Hassan A, Gleeson J, Featherstone H, Lim M, Murray H, Gallagher D, Westrup J, Hennessy B, Leonard G, Grogan L, Breathnach O, Horgan A, Coate L, O'Mahony D, Coate L, O'Reilly S, Gupta R, Keane M, Duffy K, O'Connor M, Kennedy J, McCaffrey J, Higgins M, Kelly C, Carney D, Gullo G, Crown J, Walshe J. Pregnancy associated breast cancer: Evaluating maternal outcomes. A multicentre study [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 P6-08-17.

e18261 Background: Clinical trials are an important tool in improving health outcomes in oncology patients. They also allow access to drugs that may otherwise be unavailable to patients. Increasingly, newer agents are associated with an increasing cost to hospitals, state budgets and insurance companies. Access to drugs through clinical trials may offset some of this cost to a hospital and health service budget. Methods: A prospective review on monthly basis was performed using known values of commercial stocks used during clinical trials in a single hospital centre during 2015. The available trial drugs were pazopanib, cabozantinib, everolimus, regorafanib, eltrombopag, azacitidine, orternerol, paclitaxel, pembrolizumab, nivolumab, ipilimumab, sunitinib, enzalutamide and vinflunine. Results: In total, 51 patients were recruited to therapeutic studies. A grand total of €1,420,501 (US$1,545,086) was saved to the hospital and state budget excluding commercially available stock. If placebo controlled trials were excluded, total savings were €1,149,445 (US$1,251,060). Conclusions: Clinical trials allow patient access to drugs that may otherwise not be available due to cost or access. Clinical trials also significantly offset the cost of these treatments to hospitals, state healthcare providers and insurance companies. Available clinical trials should be discussed with eligible patients when discussing treatment options. 2015 Direct Savings (€) Indirect Savings (€) Indirect Savings (exclu. placebo) (€) Cost of commercial stock supply (€) Grand Total Grand Total excluding placebo Jan 7,718 39,387 17,957 19 (direct savings + indirect savings - commercial stock) [direct savings + indirect savings (exclu. placebo) - commercial stock] Feb 7,718 35,697 15,845 123 Mar 15,570 51,578 33,304 239 Apr 15,503 73,688 51,427 353 May 40,258 59,057 36,795 186 Jun 42,242 66,704 44,443 333 Jul 103,103 71,410 26,870 596 Aug 74,340 71,410 49,149 943 Sep 104,999 88,206 68,728 943 Oct 91,788 71,803 52,325 313 Nov 87,288 101,063 67,672 1,166 Dec 52,472 53,467 47,902 762 Total 2015 €643,006 €783,475 €512,419 €5,980 €1,420,501 €1,149,445