Dural spread from metastatic prostate cancer

A 59-year-old man with a known breast cancer type 1 gene mutation and a 2-year history of metastatic prostate cancer to bone and lymph nodes presented with a sudden onset of thunderclap headache, photophobia and a left sided facial droop. He was being treated at the time with the poly ADP ribose polymerase inhibitor Rucaparib. Of note, 6 weeks prior to this presentation, he had been diagnosed with malignant spinal cord compression at T3-T6, he underwent an emergency decompressive laminectomy and had received palliative postoperative radiotherapy. An urgent CT brain revealed dural metastases from his prostate cancer, with extensive oedema and midline shift. He underwent palliative whole brain radiotherapy but died 2 weeks later.

PATH-09. NEXT-GENERATION SEQUENCING OF GLIOBLASTOMA MULTIFORME ‘EXTREME RESPONDERS’

BACKGROUND

Glioblastoma Multiforme (GBM) is the most common primary brain among adults. Despite steady advances in treatment, the outcome remains universally lethal. Median overall survival in a population-based study is approximately 10 to 12 months. Prognostic factors in GBM patients include age, performance score, extent of surgical resection, IDH1 mutation status and MGMT methylation status. Survival > 2 years is rare; for the purpose of this study we have defined these patients ‘extreme responders.’ This study aims to identify genomic signatures and gene alterations that may have contributed to ‘extreme response’ to standard adjuvant chemoradiotherapy.

METHODS

A total of 12 out of 141 primary GBM patients were identified as ‘extreme responders’ as part of a retrospective chart review between 2005 - 2016. Of the 12 suitable for NGS testing, 9 were analyzed using the Foundation One CDx® (next-generation sequencing platform) which interrogates 324 genes, microsatellite status and tumour mutational burden (TMB). Baseline demographics, clinical characteristics, and NGS results were compared.

RESULTS

Of the 9 patients tested, over half were female (5, 55%) and median age at diagnosis was 53 years. Gross total resection was performed at diagnosis in 3 cases. MGMT status was available for 5 patients and was methylated in 3. NGS results revealed: MSI stable in all patients, median TMB 3 muts/Mb and most common gene alterations were TP53 (5/9); ATRX (4/9); EGFR (3/9); CDKN2A/B (3/9); IDH1(3/9); PIK3R1(3/9) and PTEN (3/9).

CONCLUSION

Acknowledging the fact that our sample size was small and no control group was tested, our study infers a higher incidence of IDH1, TP53 and ATRX mutations which are more common in secondary glioblastomas and this may be a contributing factor towards longer survival in our cohort. We did not identify any universal molecular marker predictive of improved prognosis or exquisite sensitivity to chemoradiotherapy.

Radium-223 in the treatment of metastatic castrate-resistant prostate cancer: A real-world Irish experience

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Background: Radium 223 (Ra-223) has been successfully utilised in the trial setting for the treatment of men with metastatic castrate resistant prostate cancer (mCRPC). To date, no real world outcomes from its use in the Irish population have been described. Methods: From September 2016 to March 2019, data from men referred for Ra-223 treatment at our institution was retrospectively collected. We recorded patient characteristics, treatments received and outcomes. Overall Survival (OS) was analysed using the Kaplan-Meier method. Results: 81 men were referred for Ra 223. Complete data was available for 56 men. Median age was 75. 79%(45/56) had over 6 bone metastases and 21%(12/56) had lymph node involvement. The median number of prior systemic treatments for mCRPC was 2. 84%(47/56) of patients were previously treated with Androgen deprivation therapy (ADT); 48%(27/56) Abiraterone, 36%(20/56) Docetaxel, 45%(25/56) Enzalutamide and 9%(5/56) Cabazitaxel. All patients were receiving bone protection agents; 57%(32/56) Zolendronic acid and 43%(24/56) Denosumab. Median ECOG was 1 at the start of treatment and 2 at completion. The median number of treatments received was 4 with 36%(20/56) completing all 6 treatments. The most common toxicity seen was grade1 fatigue occurring in10% (6/56). 17% (10/56) required a blood transfusion during their treatment course. 53%(30/56) required opioid analgesia prior to Ra 223 treatment. 76% of these men (22/30) described improved pain following Rad-223. At a median follow up of 13 months,41%(23/56) were alive. The median OS for the entire group was 7 months. Factors associated with improved OS included ECOG 0-1,fewer than 6 bone metastases, normal alkaline phosphatase level at start of treatment and no prior chemotherapy use. Median OS for those who had not received prior chemotherapy was significantly better than those who had (9 vs 5 months p=0.04). Conclusions: This real world study demonstrates Ra 223 is a well tolerated palliative treatment amongst Irish men with mCRPC. Good performance status, lower alkaline phosphatase, chemotherapy naivety and a low burden of metastatic disease are factors associated with an improved overall survival.

Unique perspectives from the transgender community: A retrospective chart review of cancer care needs for transgender patients

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Background: It is estimated that 1% of a population experience some degree of gender non-conformity. There is scant information worldwide on cancer incidence and mortality for this population however due to a lack of investigating large-scale prospective studies. National cancer registries do not hold demographics on this population. Current literature indicates transgender people may face an increased cancer risk. Transgender patients may avoid screening programmes for cancers which are themselves gendered. Transgender patients can feel excluded from gender specific cancer support groups. We set out to identify how cancer services in Ireland can better meet transgender people’s unique needs. Methods: Medical oncology consultants in the South/South-West of Ireland were contacted to identify patients who identified as transgender or gender non-conforming. We carried out a retrospective chart review of the four transgender patients identified. We analysed staging at diagnosis, family supports, smoking history, alcohol use and whether cancer treatment affected gender transitioning treatment and if this had documented effects on mental well-being. We also noted if medical records reflected a new name or change of gender and if not, whether original name and gender used for chemotherapy and blood product administration. Results: All four patients were diagnosed with relatively advanced disease at diagnosis- Stage IIIc high grade ovarian cancer, stage IV gastrointestinal tumour, stage IVb diffuse large B Cell and locally advanced extra-abdominal desmoid tumour. Of the four patients, three had a smoking and alcohol history on diagnosis. All four patient’s recent medical correspondence reflected a name and gender change but the medical records did not reflect this. Three patients had documented depression for which they were attending psychiatry services. It was noted that two patients had gender transitioning treatment postponed due to cancer care. Minimal family support was noted for two patients. Conclusions: The transgender community is a growing population that will continue to integrate into mainstream society. Our retrospective chart review adds to a growing body of evidence which suggests gender minorities may suffer from cancer-related disparities and have an increased need for psychosocial support. As in other studies, it is difficult to identify these individuals. We should identify gender minority individuals and report this data in medical records in order to build much needed epidemiological information.

End-of-life care and immune checkpoint inhibitors

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Background: In the era of cytotoxic chemotherapy, aggressive cancer treatment and hospitalization at the end of life (EOL) has been associated with a worse quality of death. Meanwhile, in the era of immunotherapy (IO), little is known of the impact of these novel agents on EOL care. The aim of this study was to evaluate the EOL care of metastatic cancer patients treated with immune checkpoint inhibitors. Methods: We conducted a retrospective analysis of patients prescribedPD1/L1 or CTLA-4 antibodies in Cork University Hospital (CUH) and Mercy University Hospital (MUH) between January 2013 to December 2018. Patients treated on a clinical trial were excluded. Results: We identified 224 patients treated with immune checkpoint inhibitors (outside of a clinical trial) in CUH and MUH over the described 6 year period. 108 of these patients were deceased, 102 electronic files were available for analysis. Of the 102 patients, 57 had metastatic melanoma, 33 non small cell lung cancer, 8 renal cell carcinoma, 4 had other advanced malignancies. 43% were female and 57% were male. 6% of patients had an ECOG performance status (PS) of 0 at diagnosis, 80% PS of 1 and 10% PS of 2. Median age at death was 62 years. 47 patients were treated with pembrolizumab, 26 nivolumab, 25 ipilimumab, 2 nivolumab/ipilimumab and 2 received atezolizumab. 29 patients received IO as first line treatment, 50 as second line, 17 as third line and 6 as fourth line. Median number of IO cycles received was 4 (range 1 - 41). Progression of disease (62%) and declining performance status (14%) were the most common reasons for discontinuation of IO treatment. 16 of the 102 patients received a further line of systemic therapy. Median time from last dose of IO to death was 57 days. 20 patients (20%) died within 30 days of last dose of IO. Of these 20 patients, the median number of cycles of IO received was 2 (range 1-7), 8 of these 20 patients received one cycle of IO only. 39 patients (38%) attended the ED in the last month of life. 47 (46%) patients had at least one hospital admission in the last month of life, the median hospital length of stay was 6 days (range 1-30) and 22 patients died in hospital. 94% of patients were referred to palliative care, the median time from palliative care referral to death was 64 days (range 1- 1010), 62% of patients died in hospice. Conclusions: Patients with advanced cancer treated with immunotherapy have high rates of hospital admissions and ED attendances despite early palliative care involvement. 20% of patients died within 30 days of IO. More research is needed to help physicians identify patients who are least likely to benefit from IO so as not to treat futile cases.

Clinical utility of Oncotype DX in early stage colon cancer

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Background: With the advent of colon cancer screening, patients with early stage colon cancer will be more common in our clinics. The evidence supporting the absolute benefit of chemotherapy in resected Stage II and (to a lesser extent) Stage IIIA disease is poor. Not all patients benefit from chemotherapy and toxicity is a problem. There is a need for validated biomarkers to assess individual patient recurrence risk and discriminate absolute treatment benefit. Several studies have validated the role of the OncotypeDX testing in Stage II/IIIA disease. Our objective is to characterize whether this test impacted oncologists’ decisions in treating patients with Stage II/IIIA in the adjuvant setting. Methods: :The Onco typeDX assay is a multi-gene reverse-transcriptase-polymerase-chain-reaction test that analyses the expression of 12 genes involved in key biologic pathways in colon cancer. Stage II and Stage IIIA colon cancers were studied in affiliated hospitals of our region in southwest Ireland. All data collected is prospective and each colon cancer was assigned a recurrence risk score. Oncologists were blinded to this score and the decision to prescribe adjuvant chemotherapy was recorded. After un-blinding the score, a second decision was recorded and comparisons made. Results: :From August 2015 to September 2016, 70 patients have been recruited with M: F of 2:1. Median age at diagnosis was 65 years. Most patients (80%) had stage II disease, 11 of whom had mismatch repair loss on IHC. OncotypeDX testing has been carried out and reported for 59 patients (85%), MMR intact. Recurrence scores: < 30 in 46 patients (77.9%), 30-40 in 10 patients, and > 40 in 3 patients. The treatment plan was altered in 16 patients (27%), of whom 12 patients (20%) received none or less intense chemotherapy. Conclusions: We have shown that the decision to prescribe adjuvant chemotherapy was changed in 27% of patients. This test has helped to define patients with low scores, where chemotherapy-related toxicity is a concern especially in older patients. Absolute benefit of adjuvant chemotherapy versus the risk of toxicity should be discussed. . Hospital managers may be interested in cost savings due to a reduction in chemotherapy use.

Association of AR-V7 on Circulating Tumor Cells as a Treatment-Specific Biomarker With Outcomes and Survival in Castration-Resistant Prostate Cancer

Importance

A critical decision in the management of metastatic castration-resistant prostate cancer (mCRPC) is when to administer an androgen receptor signaling (ARS) inhibitor or a taxane.

Objective

To determine if pretherapy nuclear androgen-receptor splice variant 7 (AR-V7) protein expression and localization on circulating tumor cells (CTCs) is a treatment-specific marker for response and outcomes between ARS inhibitors and taxanes.

Design, Setting, and Participants

For this cross-sectional cohort study at Memorial Sloan Kettering Cancer Center, 265 men with progressive mCRPC undergoing a change in treatment were considered; 86 were excluded because they were not initiating ARS or taxane therapy; and 18 were excluded for processing time constraints, leaving 161 patients for analysis. Between December 2012 and March 2015, blood was collected and processed from patients with progressive mCRPC immediately prior to new line of systemic therapy. Patients were followed up to 3 years.

Main Outcomes and Measures

Prostate-specific antigen (PSA) response, time receiving therapy, radiographic progression-free survival (rPFS), and overall survival (OS).

Results

Overall, of 193 prospectively collected blood samples from 161 men with mCRPC, 191 were evaluable (128 pre-ARS inhibitor and 63 pretaxane). AR-V7-positive CTCs were found in 34 samples (18%), including 3% of first-line, 18% of second-line, and 31% of third- or greater line samples. Patients whose samples had AR-V7-positive CTCs before ARS inhibition had resistant posttherapy PSA changes (PTPC), shorter rPFS, shorter time on therapy, and shorter OS than those without AR-V7-positive CTCs. Overall, resistant PTPC were seen in 65 of 112 samples (58%) without detectable AR-V7-positive CTCs prior to ARS inhibition. There were statistically significant differences in OS but not in PTPC, time on therapy, or rPFS for patients with or without pretherapy AR-V7-positive CTCs treated with a taxane. A multivariable model adjusting for baseline factors associated with survival showed superior OS with taxanes relative to ARS inhibitors when AR-V7-positive CTCs were detected pretherapy (hazard ratio, 0.24; 95% CI, 0.10-0.57; P = .035).

Conclusions and Relevance

The results validate CTC nuclear expression of AR-V7 protein in men with mCRPC as a treatment-specific biomarker that is associated with superior survival on taxane therapy over ARS-directed therapy in a clinical practice setting. Continued examination of this biomarker in prospective studies will further aid clinical utility.

Abstract 4954: Nuclear localized AR-V7 protein as a predictive biomarker for treatment selection in metastatic castration resistant prostate cancer (mCRPC)

Background: A critical decision in the management of patients (pts) with mCRPC is when to administer an androgen receptor signaling (ARS) directed or a taxane therapy. The detection of AR-V7 mRNA in CTCs has been shown to predict for resistance to ARS,but not to taxane chemotherapy. We evaluated the relationship between AR-V7 protein expression and localization on CTCs to treatment outcomes in a separate, larger cohort as a predictive biomarker for clinical decision making.

Methods: 193 prospectively collected blood samples from 161 unique pts with progressive mCRPC about to start an ARS or taxane therapy were evaluated with an Epic Sciences CTC immunoflorescent assay that assesses CTC AR-V7 protein expression and localization in individual

cells. Associations between the presence AR-V7(+) CTCs pre-therapy and anti-tumor effects post-therapy included prostate-specific antigen (PSA) changes, radiographic progression free survival (rPFS), time on therapy, and overall survival (OS).

Results: 130 pre-ARS inhibitor and 63 pre-taxane samples were assessed of which 191 (99%) were evaluable. AR-V7(+) CTCs were found in 34 (18%) samples including 3% of the 1st, 18% of the 2nd and 31% of the 3rd+ line baseline pre-therapy samples. Patients with AR-V7 positive CTCs in a pre-ARS sample showed no PSA response and had shorter rPFS, time on therapy, and OS than those without AR-V7(+) CTCs. PSA resistance to ARS was also seen in 65 of 112 (58%) of the AR-V7(-) samples. There was no association between PSA response, rPFS, and time on therapy between AR-V7(+) and AR-V7(-) pts treated with taxane therapy. In a multivariate model adjusting for age, type of therapy, line of therapy, and pre-therapy LDH, Hgb, and presence of visceral metastasis, AR-V7(+) pts had a superior OS on taxane therapy relative to ARS (HR: 0.242, CI: 0.103 to 0.569, p = 0.0350). Conclusions: The results validate the expression of the AR-V7 protein in the nucleus of CTCs in men with mCRPC as a treatment specific biomarker that predicts resistance to ARS inhibitor therapy and separately, clinical benefit with taxane therapy over ARS-directed therapy in a clinical practice setting. Continued examination of this biomarker in prospective studies will further determine its clinical utility.

Citation Format: Howard I. Scher, David Lu, Nicole A. Schreiber, Jessica Louw, Ryon P. Graf, Ann Johnson, Adam Jendrisak, Glenn Heller, Richard Bambury, Herbert A. Vargas Alverez, Brigit McLaughlin, Justin Wahl, Stephanie Greene, Martin Fleisher, Ryan Dittamore. Nuclear localized AR-V7 protein as a predictive biomarker for treatment selection in metastatic castration resistant prostate cancer (mCRPC). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4954.

HER2 as a target in invasive urothelial carcinoma

We evaluated primary tumors from two cohorts, Spain (N = 111) and Greece (N = 102), for patients who were treated with platinum-based chemotherapy. Patients were tested for HER2 status (IHC score of 3+ or FISH ratio of ≥ 2.2) by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), DNA copy number, mRNA expression, and mutation status in patients with metastatic urothelial carcinoma (UC), and its impact on survival. ERBB2 mutation was determined by hotspot sequencing. mRNA expression was assessed using NanoString counting. Association of overall survival (OS) and HER2 status was assessed by a Cox regression model. NIH-3T3 cells containing HER2 V777L were assessed for growth, invasion, and HER2 kinase activation. In all, 22% of Spanish and 4% of Greek cohorts had 3+ HER2 staining by IHC. FISH amplification was identified in 20% of Spanish and 4% of Greek cohorts. Kappa coefficient between FISH and IHC was 0.47. HER2 status was not associated with OS in univariate (Spanish P = 0.34; Greek P = 0.11) or multivariate (Spanish P = 0.49; Greek P = 0.12) analysis. HER2-positive tumors expressed higher levels of HER2 mRNA than HER2-negative tumors (P < 0.001). HER2 mutations (V777L and L755S) were identified in two (2%) patients. In vitro analysis of V777L results in transformation of NIH-3T3 cells, leading to increased growth, invasion on soft agar, and HER2 kinase constitutive activation. In summary, HER2 overexpression or amplification in the primary tumor did not predict OS in patients with metastatic UC. HER2 positivity rates can differ between different populations. Further trials in genomically screened patients are needed to assess HER2-targeted therapies in UC.

Somatic ERCC2 mutations correlate with cisplatin sensitivity in muscle-invasive urothelial carcinoma

Cisplatin-based chemotherapy is the standard of care for patients with muscle-invasive urothelial carcinoma. Pathologic downstaging to pT0/pTis after neoadjuvant cisplatin-based chemotherapy is associated with improved survival, although molecular determinants of cisplatin response are incompletely understood. We performed whole-exome sequencing on pretreatment tumor and germline DNA from 50 patients with muscle-invasive urothelial carcinoma who received neoadjuvant cisplatin-based chemotherapy followed by cystectomy (25 pT0/pTis "responders," 25 pT2+ "nonresponders") to identify somatic mutations that occurred preferentially in responders. ERCC2, a nucleotide excision repair gene, was the only significantly mutated gene enriched in the cisplatin responders compared with nonresponders (q < 0.01). Expression of representative ERCC2 mutants in an ERCC2-deficient cell line failed to rescue cisplatin and UV sensitivity compared with wild-type ERCC2. The lack of normal ERCC2 function may contribute to cisplatin sensitivity in urothelial cancer, and somatic ERCC2 mutation status may inform cisplatin-containing regimen usage in muscle-invasive urothelial carcinoma.

SIGNIFICANCE

Somatic ERCC2 mutations correlate with complete response to cisplatin-based chemosensitivity in muscle-invasive urothelial carcinoma, and clinically identified mutations lead to cisplatin sensitivity in vitro. Nucleotide excision repair pathway defects may drive exceptional response to conventional chemotherapy.

Ipilimumab in metastatic malignant melanoma: The Irish experience

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Background: Ipilimumab (Ipi) is a potent anti CLA-4 immunotherapy recently shown to improve overall survival (OS) in a phase III study in patients (pts) with previously-treated, unresectable or metastatic malignant melanoma. Ipilimumab (3 mg/kg) has been available on compassionate grounds to pts in Ireland since June 2010. Methods: In this retrospective observational study we examine the Irish experience with ipilimumab specifically regarding patient-factors, treatment toxicity, and outcomes including response rate and survival. Results: Between June 2010 and December 2011, a total of 93 patients received ipilimumab. Data available for analyses was conducted in 46patients. Median age of patients was 56 yrs (ranging 28 – 84). M1c disease was identified in 40 patients (83.3%). Median number of prior lines of chemotherapy is 1 (ranging from 1-4). 22 (47.8%) patients received all four planned induction doses of ipilimumab. All patients received full doses of treatment and on schedule. There are no grade 4 toxicities reported and 13% (n= 6) had grade 3 adverse events. This included renal autoimmune toxicity (n=3), diarrhoea (n=1) elevated AST/ALT (n=1), ocular toxicity (n=1) and skin (n=1). Grade 3 adverse events occurred in 3 patients who received all 4 cycles of Ipilimumab. No intestinal perforations or hypophysitis were noted. There were no drug-related deaths. From available survival follow-up data there are 22 reported deaths. Due to paucity of the data, surrogate marker for response of treatment was expressed as absence of disease progression at the time of assessment. Among the 11 (23.9%) patients who responded to treatment, 45.5% of these patients received 4 cycles of ipilimumab. Conclusions: Ipilimumab was well tolerated with a manageable side effect profile. Response rates to ipilimumab in metastatic melanoma in an Irish population are in keeping with internationally reported figures. Comprehensive survival data will be reported as well as correlation of response with hematologic and biochemical blood tests.