Lenvatinib Plus Pembrolizumab Versus Sunitinib in First-Line Treatment of Advanced Renal Cell Carcinoma: Final Prespecified Overall Survival Analysis of CLEAR, a Phase III Study

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We present the final prespecified overall survival (OS) analysis of the open-label, phase III CLEAR study in treatment-naïve patients with advanced renal cell carcinoma (aRCC). With an additional follow-up of 23 months from the primary analysis, we report results from the lenvatinib plus pembrolizumab versus sunitinib comparison of CLEAR. Treatment-naïve patients with aRCC were randomly assigned to receive lenvatinib (20 mg orally once daily in 21-day cycles) plus pembrolizumab (200 mg intravenously once every 3 weeks) or sunitinib (50 mg orally once daily [4 weeks on/2 weeks off]). At this data cutoff date (July 31, 2022), the OS hazard ratio (HR) was 0.79 (95% CI, 0.63 to 0.99). The median OS (95% CI) was 53.7 months (95% CI, 48.7 to not estimable [NE]) with lenvatinib plus pembrolizumab versus 54.3 months (95% CI, 40.9 to NE) with sunitinib; 36-month OS rates (95% CI) were 66.4% (95% CI, 61.1 to 71.2) and 60.2% (95% CI, 54.6 to 65.2), respectively. The median progression-free survival (95% CI) was 23.9 months (95% CI, 20.8 to 27.7) with lenvatinib plus pembrolizumab and 9.2 months (95% CI, 6.0 to 11.0) with sunitinib (HR, 0.47 [95% CI, 0.38 to 0.57]). Objective response rate also favored the combination over sunitinib (71.3% v 36.7%; relative risk 1.94 [95% CI, 1.67 to 2.26]). Treatment-emergent adverse events occurred in >90% of patients who received either treatment. In conclusion, lenvatinib plus pembrolizumab achieved consistent, durable benefit with a manageable safety profile in treatment-naïve patients with aRCC.

Prognostic and predictive role of immune microenvironment in colorectal cancer

Colorectal cancer (CRC) represents a molecularly heterogeneous disease and one of the most frequent causes of cancer-related death worldwide. The traditional classification of CRC is based on pathomorphological and molecular characteristics of tumor cells (mucinous, ring-cell carcinomas, etc.), analysis of mechanisms of carcinogenesis involved (chromosomal instability, microsatellite instability, CpG island methylator phenotype) and mutational statuses of commonly altered genes (KRAS, NRAS, BRAF, APC, etc.), as well as expression signatures (CMS 1-4). It is also suggested that the tumor microenvironment is a key player in tumor progression and metastasis in CRC. According to the latest data, the immune microenvironment can also be predictive of the response to immune checkpoint inhibitors. In this review, we highlight how the immune environment influences CRC prognosis and sensitivity to systemic therapy.

Lenvatinib plus pembrolizumab versus sunitinib as first-line treatment of patients with advanced renal cell carcinoma (CLEAR): extended follow-up from the phase 3, randomised, open-label study

BACKGROUND

In the primary analysis of the CLEAR study, lenvatinib plus pembrolizumab significantly improved progression-free survival and overall survival versus sunitinib in patients with advanced renal cell carcinoma (data cutoff Aug 28, 2020). We aimed to assess overall survival based on 7 months of additional follow-up.

METHODS

This is a protocol-prespecified updated overall survival analysis (data cutoff March 31, 2021) of the open-label, phase 3, randomised CLEAR trial. Patients with clear-cell advanced renal cell carcinoma who had not received any systemic anticancer therapy for renal cell carcinoma, including anti-vascular endothelial growth factor therapy, or any systemic investigational anticancer drug, were eligible for inclusion from 200 sites (hospitals and cancer centres) across 20 countries. Patients were randomly assigned (1:1:1) to receive lenvatinib (20 mg per day orally in 21-day cycles) plus pembrolizumab (200 mg intravenously every 21 days; lenvatinib plus pembrolizumab group), lenvatinib (18 mg per day orally) plus everolimus (5 mg per day orally; lenvatinib plus everolimus group [not reported in this updated analysis]) in 21-day cycles, or sunitinib (50 mg per day orally, 4 weeks on and 2 weeks off; sunitinib group). Eligible patients were at least 18 years old with a Karnofsky performance status of 70 or higher. A computer-generated randomisation scheme was used, and stratification factors were geographical region and Memorial Sloan Kettering Cancer Center prognostic groups. The primary endpoint was progression-free survival assessed by independent imaging review according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). In this Article, extended follow-up analyses for progression-free survival and protocol-specified updated overall survival data are reported for the intention-to-treat population. No safety analyses were done at this follow-up. This study is closed to new participants and is registered with ClinicalTrials.gov, NCT02811861.

FINDINGS

Between Oct 13, 2016, and July 24, 2019, 1417 patients were screened for inclusion in the CLEAR trial, of whom 1069 (75%; 273 [26%] female, 796 [74%] male; median age 62 years [IQR 55-69]) were randomly assigned: 355 (33%) patients (255 [72%] male and 100 [28%] female) to the lenvatinib plus pembrolizumab group, 357 (33%) patients (275 [77%] male and 82 [23%] female) to the sunitinib group, and 357 (33%) patients to the lenvatinib plus everolimus group (not reported in this updated analysis). Median follow-up for progression-free survival was 27·8 months (IQR 20·3-33·8) in the lenvatinib plus pembrolizumab group and 19·4 months (5·5-32·5) in the sunitinib group. Median progression-free survival was 23·3 months (95% CI 20·8-27·7) in the lenvatinib plus pembrolizumab group and 9·2 months (6·0-11·0) in the sunitinib group (stratified hazard ratio [HR] 0·42 [95% CI 0·34-0·52]). Median overall survival follow-up was 33·7 months (IQR 27·4-36·9) in the lenvatinib plus pembrolizumab group and 33·4 months (26·7-36·8) in the sunitinib group. Overall survival was improved with lenvatinib plus pembrolizumab (median not reached [95% CI 41·5-not estimable]) versus sunitinib (median not reached [38·4-not estimable]; HR 0·72 [95% CI 0·55-0·93]).

INTERPRETATION

Efficacy benefits of lenvatinib plus pembrolizumab over sunitinib were durable and clinically meaningful with extended follow-up. These results support the use of lenvatinib plus pembrolizumab as a first-line therapy for patients with advanced renal cell carcinoma.

FUNDING

Eisai and Merck Sharp & Dohme.

Agreement between FGFR2 immunohistochemistry assays and fluorescence in situ hybridization (FISH) in metastatic gastric cancer: A comparison study

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Background: FGFR2 status of a patient with metastatic gastric adenocarcinoma could be an important factor in determining optimal treatment strategy with FGFR2 inhibitors and antibodies. The question remains how well different assays agree on the FGFR2 status of the same patient and whether one test can be substituted by another. Methods: Pairwise comparison of 4 tests based on the same patient population was performed: 3 IHC assays [Abcam clone EPR24075-418, R&D clone 98706, Santa Cruz clone C-8] and one FISH test. One hundred and nine formalin-fixed, paraffin embedded samples (including 64 primary tumors and 45 metastases of same patients) were obtained and were stained with FGFR2 IHC assays. Two trained pathologists independently evaluated the percentages of tumor staining and their intensity. FGFR2 FISH was performed as described previously [Su, BJC 2014]. The concordance analysis was performed to assess (1) correlation of FGFR2 expression/amplification between different assays in primary and metastases, (2) the predictive properties of one test of another. Results: After evaluating the expression in the first 19 patients, further study was carried out only using the Abсam assay due to pronounced nuclear staining with other IHC tests. FGFR2 any level expression was detected in 29 (47%) primary tumors and 18 (40%) metastases with concordance of 91%. The prevalence of FGFR2 amplification was 9.4% and intratumoral heterogeneity was observed in 33% of FGFR2 amplified cases. Pearson Correlation Coefficients (PCC) were: 0.89, 0.38 and 0.35 between IHC3+/FISH, IHC≥1% stained cells/FISH and IHC≥10%/FISH, respectively. The table represents how well one assay can predict the same outcome (positivity or negativity) of another assay. Conclusions: Among patients who were negative by FISH, 86%-93% of the patients were negative by IHC assay (Abcam). Among patients who were positive by FISH, 75-80% of them were positive by IHC. FISH should not be recommended as a substitute for a FGFR2 IHC assay due to high probability of false negative prediction as a result of intratumoral heterogeneity and low PCC. [Table: see text]

Patterns of Care and Barriers to Utilization of Definitive Concurrent Chemoradiation Therapy for Stage III Non-Small Cell Lung Cancer in Russia

BACKGROUND

Definitive concurrent chemoradiation (cCRT) is offered to only 3% of Russian patients with stage III NSCLC. To determine the patterns of care and barriers to cCRT utilization in Russia, we conducted a survey of practicing radiation oncologists (ROs).

METHODS

Electronic IRB-approved survey containing 15 questions was distributed to Russian ROs. Fisher's exact test or Cochran-Armitage test of trend was used to assess the associations between clinical experience, practice type, and patterns of care.

RESULTS

We analyzed 58 questionnaires completed by ROs-16 respondents from tertiary referral hospitals, and 42 from community or private centers. A total of 88% of respondents formulate treatment recommendations in multi-disciplinary tumor boards. For unresectable stage III NSCLC, the most common recommendation is sequential CRT (50%), followed by concurrent CRT (40%), with an observed higher utilization of cCRT in tertiary centers (9/16, 56% vs 14/42, 33%). Of the respondents, 31% do not offer cCRT to their pts. Among reasons for avoiding cCRT are (1) poor performance of pts (76%); (2) high toxicity of therapy (55%); (3) lack of consensus among tumor board members (33%); and (4) preference for sequential CRT (31%). Only 3% do not irradiate elective LNs. Eighty-six percent of respondents counsel their NSCLC pts regarding smoking cessation.

CONCLUSIONS

Despite level 1 evidence, cCRT is rarely used in Russia for pts with locally advanced NSCLC, and preference for sequential therapy and concerns over high toxicity are the most common barriers. Education of Russian ROs may increase cCRT utilization, leading to improved survival, notably in the era of maintenance immunotherapy.

Randomized, Double-Blind, Placebo-Controlled Phase III Study of Paclitaxel ± Napabucasin in Pretreated Advanced Gastric or Gastroesophageal Junction Adenocarcinoma

PURPOSE

To compare napabucasin (generator of reactive oxygen species) plus paclitaxel with paclitaxel only in patients with second-line advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma.

EXPERIMENTAL DESIGN

In the double-blind, phase III BRIGHTER study (NCT02178956), patients were randomized (1:1) to napabucasin (480 mg orally twice daily) plus paclitaxel (80 mg/m2 i.v. weekly for 3 of 4 weeks) or placebo plus paclitaxel. The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety.

RESULTS

Overall, 714 patients were randomized (napabucasin plus paclitaxel, n = 357; placebo plus paclitaxel, n = 357). 72.1% were male, 74.6% had gastric adenocarcinoma, and 46.2% had peritoneal metastases. The study was unblinded following an interim analysis at 380 deaths. The final efficacy analysis was performed on 565 deaths (median follow-up, 6.8 months). No significant differences were observed between napabucasin plus paclitaxel and placebo plus paclitaxel for OS (6.93 vs. 7.36 months), PFS (3.55 vs. 3.68 months), ORR (16% vs. 18%), or DCR (55% vs. 58%). Grade ≥3 adverse events occurred in 69.5% and 59.7% of patients administered napabucasin plus paclitaxel and placebo plus paclitaxel, respectively, with grade ≥3 diarrhea reported in 16.2% and 1.4%, respectively.

CONCLUSIONS

Adding napabucasin to paclitaxel did not improve survival in patients with pretreated advanced gastric or GEJ adenocarcinoma. Consistent with previous reports, the safety profile of napabucasin was driven by manageable gastrointestinal events; grade ≥3 diarrhea occurred at a higher frequency with napabucasin plus paclitaxel versus placebo plus paclitaxel.

Abstract 3481: Pharmacokinetics of alofanib and biomarker analysis in patients with advanced gastric cancer: A phase 1b study

Alofanib is a potent, small molecule, allosteric inhibitor that binds to the non-active extracellular site of IIIc and IIIb FGFR2 isoforms. Phase 1b clinical study (RPT835GC1B) met its primary endpoints and recommended phase 2 dose was described early. Here, we present pharmacokinetics (PK) and results of biomarker analysis.

Alofanib was administered daily intravenously for 5-days followed by a 2-day interval (rest). There were five dose levels using a 3 + 3 design. 21 patients have been enrolled in the study. Patients were Caucasian (100%), predominantly male (71%), 67% had 2 and more metastatic sites, including liver (43%) and bone (14.3%) metastases, 19% had ECOG PS 2, and were heavily pretreated (86% had previous 3 and more lines of therapy). The PK and biomarker analysis set included 18 patients. FGFR2 amplification was accessed by FISH with ZytoLight SPEC FGFR2/CEN 10 Dual Color Probe and FGFR2 expression was accessed by IHC with antibody 1G3 (Abcam (ab 5820).

Table summarizes PK data. The geometric mean values of Cmax, AUC0-t, T1/2, Vd increased and CL, Kel decreased approximately dose-proportionally after single dosing, similar to previous preclinical studies. The decrease in the mean value of the Vd for a dose of 350 mg/m2 may be associated with a significant increase in AUC0-t. No correlations between PK values and objective response rate (n=2; 9.5%), progression-free (median 3.63 months (95% CI, 1.58 - 5.68) and overall (median 7.0 months (3.82 - 10.18) survival as well as in patients with liver metastases were found (all P>0.1). A positive FGFR2 IHC expression was observed in all tumor cells and a weak positive reaction in normal epithelium. FGFR2 amplification was confirmed by FISH in 1 (5.6%) patient.Alofanib PK in a gastric patient population is well characterized, supporting the use of a once-daily 350 mg/m2 dose. In further studies, the evaluation of FGFR2 amplification seems to be important.

Cohort 1 Cohort 2 Cohort 3 Cohort 4 Cohort 5 50 mg/m2 100 mg/m2 165 mg/m2 250 mg/m2 350 mg/m2 Cmax, mcg/ml (CV%) 21.4 (32.3) 23.7 (18.4) 44.7 (15.5) 72.8 (64.3) 145.9 (42.7) AUC0-t, mcg*h/ml (CV%) 2.3 (31.9) 6.6 (14.2) 13.3 (49.9) 23.8 (8.7) 74.0 (57.5) Vd, ml/m2 (CV%) 4006.1 (28.3) 4907.5 (14.7) 5676.8 (26.6) 6686.7 (11) 3823.0 (63.8) CL, ml/h/m2 (SD) 19609.5 (7740) 14028.2 (1990) 11910.5 (8740) 10011.0 (827) 4183.0 (2420) Kel, 1/h (CV%) 4.9 (15.3) 2.9 (2.8) 2.1 (41.2) 1.5 (3.8) 1.1 (47.0) T1/2, h (SD) 0.1 (0.024) 0.2 (0.01) 0.3 (0.118) 0.5 (0.0171) 0.6 (0.293)

Citation Format: Grigory Raskin, Vasily Kazey, Svetlana Gorbacheva, Aiyyna Nikiforova, Galina Statsenko, Elena Artamonova, Liubov Vladimirova, Natalia Besova, Anastasia Mochalova, Ivan Rykov, Vladimir Moiseyenko, Igor Utyashev, Sergei Iugai, Nadezhda Dragun, Dmitry Reznikov, Evgenia Gavrilova, Sergei Tjulandin, Ilya Tsimafeyeu. Pharmacokinetics of alofanib and biomarker analysis in patients with advanced gastric cancer: A phase 1b study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3481.

Prognosis of patients with resected stage II colon cancer -T4 versus T3 with two or more high-risk factors: A retrospective single-center cohort study

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Background: in 2021 ASCO has updated guidelines on adjuvant therapy for stage II colon cancer with the statement: “Patients with T4 tumors are at higher risk of recurrence and should be offered adjuvant chemotherapy, whereas patients with other high-risk factors, including sampling of fewer than 12 lymph nodes in the surgical specimen, perineural or lymphatic invasion, poorly or undifferentiated tumor grade, intestinal obstruction, tumor perforation, or grade BD3 tumor budding, may be offered ACT”. We performed a single-center retrospective study to assess the prognostic role of postoperative tumor stage T4 and T3 with ≥2 negative prognostic factors in patients with resected stage II colon cancer. Methods: We retrospectively analyzed 1457 pts with stage I-III colon cancer treated in Russian Cancer Research Center n.a. N.N. Blokhin from 2001 to 2015. We included pts with resected stage II colon cancer with following negative prognostic factors: T4; sampling of fewer than 12 lymph nodes in the surgical specimen; perineural or lymphatic invasion; poorly or undifferentiated tumor grade; intestinal obstruction; and tumor perforation. Three cohorts were studied: pts with pT4N0M0 with no other high-risk factors (group A), pts with pT4N0M0 with additional high-risk factors (group B), and pts with pT3N0M0 with ≥2 high-risk factors (group C). The primary study endpoint was 3-year disease-free survival (DFS). The secondary endpoint was 5-year overall survival (OS). Statistical analysis was done with SPSS v.20. Results: 164 pts met the inclusion criteria with 17 (10%) pts in group A, 90 (55%) pts in group B, and 57 (35%) pts in group C. Adjuvant chemotherapy was performed in 8 (47%), 25 (28%), and 9 (16%) pts, respectively (p = 0.035). At a median follow-up of 62 months (range, 2-135 months), the 3-year DFS was 82%, 68%, and 78% for groups A, B, and C, respectively (HR, 1.55; 95% CI, 0.99-2.4; p = 0.053). No difference in 3-year DFS was found between group A and C (HR, 1.0; 95% CI, 0.34-3.2; p = 0.9). The 5-year OS was 75%, 65%, and 78% for groups A, B, and C, respectively (HR, 1.38; 95% CI, 0.84-2.3; p = 0.2). Conclusions: Patients with pT4 with additional high-risk features had worse overall survival compared to other subgroups with resected stage II colon cancer. There was no difference in survival rates between patients with pT4 with no additional negative prognostic factors and pT3 with ≥2 negative prognostic factors. Therefore, we propose that patients with pT4 as well as with pT3 with ≥2 negative prognostic factors are at a higher risk of recurrence and should be offered adjuvant chemotherapy.

Treatment sequence for hormone receptor-positive HER2-negative advanced breast cancer: Results of a retrospective analysis of Russian patients diagnosed with aBC in 2014-2021

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Background: CDK4/6 inhibitors (CDK4/6i) in combination with endocrine therapy (ET) have dramatically changed therapeutic landscape of hormone receptor-positive HER2-negative advanced breast cancer (HR+ HER2- aBC). There are three iCDK4/6 in Russia, which are available and included into the clinical guidelines as a preferred first line treatment option beginning since 2018. The aim of this study was to assess evolution of treatment approaches to HR+ HER2- aBC and identify demographic and disease characteristics in correlation with available groups of therapy (chemotherapy, endocrine therapy ±mTOR inhibitors/ CDK4/6i). Methods: Аdult patients diagnosed with de novo or recurrent HR+ HER2- aBC in 2014-2021 identified in outpatient departments of Moscow state oncology hospitals were included into our non-interventional, descriptive, retrospective cohort study. Primary objective of this real-world study was to describe the rate of CDK4/6i usage in the first line setting. As a secondary objective, we describe patient and disease characteristics in iCDK4/6 group, as well as in the endocrine monotherapy and chemotherapy groups. Results: From the cohort of 1000 patients (full-set analysis population) 874 cases were selected, who received treatment since 2018. 45.9% (95% CI 42.6, 49.2) patients were treated with CDK4/6i in combination with endocrine therapy in the first-line setting. From them in the subgroups of patients with or without visceral metastases 50.5% (95% CI 45.5, 55.5) and 42.1% (95% CI 37.7, 46.5) were treated with CDK4/6i in the first line setting, respectively. Among 874 cases 78.0% (95% CI 75.3, 80.7) patients received endocrine therapy ± targeted therapy; in the subgroups of patients with or without visceral metastases 69.5% (95% CI 64.9, 74.1) and 84.9% (95% CI 81.7, 88.1) were treated with endocrine therapy ± targeted therapy in the first line setting, respectively. Conclusions: Endocrine therapy is a predominant therapeutic option in the first line setting for HR+ HER2- aBC. Clinical trial information: NCT04852081. [Table: see text]

Platinum vs non-platinum chemotherapy for platinum-resistant ovarian cancer: A meta-analysis

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Background: recurrent ovarian cancer (OC) patients with platinum-free interval (PFI) < 6 mo. are usually considered platinum-resistant and treated with non-platinum chemotherapy. However, this practice is not based on proper-conducted randomized trials. Methods: we queried the PubMed database for all full-text articles and abstracts on the treatment of patients with platinum-resistant ovarian cancer (PROC) in 01/01/2000-01/06/2019 timeframe. The PRISMA tool was used to ensure transparent reporting of the results. Inclusion criteria were: 1) histologically confirmed epithelial OC; 2) recurrent disease within 6 months after completion of platinum chemotherapy; 3) treatment with platinum- or non-platinum chemotherapy agents that are routinely used for OC; 4) no concomitant therapy with targeted or investigational agents; 5) defined response rate (RR) and assessment criteria. Proportion meta-analysis (random-effect model) and beta-regression were conducted to assess the impact of platinum agents on response rate as well as significance of other variables. In the beta-regression model response rate was a dependent variable, while platinum agents (yes or no), used non-platinum drugs and method of response assessment were independent variables. Statistical analysis was dose with meta and betareg packages of R software. Results: we identified 7156 articles and screened them for title and abstract, 157 studies for further analysis. Efficacy of non-platinum- and platinum-based therapy was assessed in 113 (n = 5272) and 44 (n = 1055) trials respectively. In meta-proportion random-effect model RR among patients treated with platinum-based and non-platinum chemotherapy RR was 36% (95% CI 30-41; I2 = 62%) and 16% (95% CI 14-19; I2= 70%) respectively. Multiple beta-regression model is presented in the Table below. For sensitivity analysis various regression models were made with different subsets of the trials and additional variables (including year of the trial, percentage of serous subtype of OC and median of prior therapy lines). Platinum was the strongest predictor of response in every developed model. Conclusions: this meta-analysis shows that patients with 'platinum-resistant' ovarian carcinoma may derive significant benefit from reintroduction of platinum agents. These results support recent ESMO-ESGO consensus on treatment of recurrent ovarian cancer and randomize trials are required to refine the role of platinum in early relapsed OC.[Table: see text]

Alofanib in subsequent therapy for advanced gastric cancer: Final results from the phase Ib clinical trial

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Background: Alofanib (RPT835) is a first-in-class allosteric inhibitor that induces conformational changes in the extracellular domain of FGFR2. Here, we present the final results of the phase Ib clinical study (RPT835GC1B) of alofanib. Methods: Patients with metastatic gastric adenocarcinoma resistant to standard therapy with measurable disease were eligible. The dose finding part used a 3+3 design, starting with a dose level of 50 mg/m2, intravenously, 5 days on, 2 days off. Five dose levels were foreseen. Primary endpoint was maximum tolerated dose (MTD). Secondary endpoints included toxicity, PK, objective response rate (ORR), overall survival (OS), and progression-free survival (PFS). Results: 21 patients were enrolled. 4 (19.1%), 14 (66.7%), 9 (43%), 3 (14.3%), and 12 (57%) patients had ECOG PS 2, ≥2 metastatic sites, liver metastases, bone metastases, and 3-6 lines previous therapy, respectively. The MTD has not been reached and dose of 350 mg/m2 has been declared as recommended phase II dose. With median follow-up of 13.0 months 15 (71.4%) patients had any grade treatment related adverse events (TRAE). Grade 3-4 TRAE occurred in 6 (28.6%) patients. Two (9.5%) patients discontinued treatment due to grade 3 diarrhea and grade 4 reactions immediately after injections. There were no treatment-related deaths in the study. One partial response (5.26%) with a duration of 18.53 months was identified. Disease control rate (DCR) was 68.4% and median duration of stable disease was 4.91 months. Median PFS was 3.63 (95% CI 1.58–5.68) months. Median OS was 7.0 (3.82–10.18) months. 6-month OS rate was 57.1%. OS was almost 2 times better in patients with DCR (median 10.05 vs. 5.9 months) and without bone metastases (8.6 vs. 3.1). Only one patient (4.8%) had FGFR2 amplification (time to death was 7 months). PK parameters linearly changed depending on the dose level, but no correlation with efficacy was found. Table summarizes rate of TRAE and DCR in dose cohorts. Conclusions: Alofanib was feasible and showed early signals of efficacy in heavily-pretreated patients with metastatic gastric cancer. A phase 2 randomized trial is planned. Clinical trial information: NCT04071184. [Table: see text]

A first-in-human phase 1b study of a novel allosteric extracellular FGFR2 inhibitor alofanib in patients with refractory metastatic gastric cancer

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Background: FGFR2 promotes gastric cancer progression, suggesting that inhibition of FGFR2 may be an important therapeutic strategy. Alofanib (RPT835) is a small molecule, allosteric inhibitor that binds to the non-active extracellular site of IIIc and IIIb FGFR2 isoforms with IC50 < 10 nM. Methods: RPT835GC1B is a Phase 1b open-label study evaluating the safety and preliminary efficacy of alofanib in patients with metastatic gastric adenocarcinoma pretreated with ≥ 1 previous lines of therapy. The standard dose-escalation part (design 3+3) aimed to establish the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) as a primary endpoint. Secondary endpoints included pharmacokinetic (PK) parameters, rate of adverse events, progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). Alofanib was administered daily intravenously for 5-days followed by a 2-day interval (rest). There were five dose levels: 50, 100, 165, 250, and 350 mg/m2. All patients received alofanib until disease progression or unacceptable toxicity. Results: As of 20 September 2021, 21 patients have been enrolled in the study. Patients were Caucasian (100%), predominantly male (71%), 67% had 2 and more metastatic sites, including liver metastases (43%), 14% had ECOG PS 2, and were heavily pretreated (86% had previous 3 and more lines of therapy). All enrolled patients have been studied for safety and have not experienced any dose-limiting toxicities (DLTs) within the 28-day DLT-assessment window. 17 (81%) patients had at least one treatment-related adverse event (trAE). Grade 3 or higher trAEs (5/23.8%) have included raised ALT/AST at 50 mg/m2, neutropenia at 50 mg/m2, diarrhea at 165 mg/m2, headache at 165 mg/m2, increased serum amylase at 350 mg/m2, and reactions immediately after intravenous injections (facial flushing, dizziness, weakness, sweating, and sinus tachycardia) at 350 mg/m2. Three (14.3%) patients discontinued treatment due to trAEs. Most common Grade 1-2 adverse events included reactions immediately after intravenous injections, diarrhea, thrombocytopenia, arthralgia, and headache. Grade 1 hyperphosphatemia was found in 1 (4.8%) patient. Table summarizes efficacy data. Conclusions: The MTD has not been reached and dose of 350 mg/m2 has been declared as RP2D. Alofanib showed acceptable tolerability and preliminary signs of clinical activity in the late-line treatment of metastatic gastric cancer. Clinical trial information: NCT04071184. [Table: see text]

Management of Muscle Invasive Bladder Cancer with Bladder Preservation in Russia: a Survey-Based Analysis of Current Practice and the Impact of an Educational Workshop on Clinical Expertise

Trimodality bladder preservation (BP) is an accepted alternative to radical cystectomy for patients with muscle invasive bladder cancer (MIBC). The global utilization of BP is variable, and practice patterns have not been previously studied in Russia. We sought to elucidate the contemporary BP practice patterns in Russia and determine the impact of the BP workshop on attitudes of Russian radiation oncologists (ROs) towards BP. The workshop was focused on patient workup, selection for BP, chemotherapy choices, radiation therapy (RT) contouring and planning, patient counseling. A total of 77 pre- and 32 matched post-workshop IRB-approved surveys, based on the workshop content, were analyzed using descriptive statistics to determine baseline clinical experience and patterns of care. The impact was judged by changes in participants' responses. A total of 56% of respondents had experience with delivering bladder-directed RT, and 60% of those treated both operable and inoperable MIBC patients. Only 10% felt uncomfortable offering an operable patient BP modality. Prior to the workshop, almost half of respondents estimated universal poor bladder (44%) and erectile functions (47%) after BP. The workshop resulted in dramatic change in participants' attitudes towards long-term urinary (Stuart-Maxwell test, p < 0.01) and sexual (exact McNemar test, p < 0.01) side effects. Prior to the workshop, only 47% of respondents routinely discussed smoking cessation (SC) with their patients, whereas after workshop, 88% agreed that SC discussion is mandatory (exact McNemar test, p = 0.04). BP for MIBC is commonly used in Russia. Our workshop resulted in dramatically improved understanding of long-term BP toxicities and inspired Russian ROs to incorporate SC counseling into routine clinical management.

Abstract CT113: Preliminary data on a phase 1b, first-in-human study of the allosteric extracellular FGFR2 inhibitor alofanib in patients with refractory metastatic gastric cancer

Fibroblast growth factor receptor 2 (FGFR2) is associated with an unfavorable prognosis in patients with gastric cancer. Acquired mutations in FGFR2 develop resistance to multikinase inhibitors. Besides, resistance to monoclonal antibodies depends on the type of FGFR2 isoforms IIIc or IIIb expressed by cancer cells. Alofanib (RPT835) is a small molecule, allosteric inhibitor that binds to the non-active site of FGFR2 extracellular domain. RPT835GC1B (NCT04071184) is an ongoing Phase 1b open-label study evaluating the safety and preliminary efficacy of alofanib in patients with metastatic gastric adenocarcinoma pretreated with ≥ 1 previous lines of therapy. The standard dose-escalation part (design 3+3) aims to establish the maximum tolerated dose (MTD) or recommended phase 2 dose (R2PD) as a primary endpoint. The first part of the study includes a 28-day period when alofanib is administered daily intravenously for 5-days followed by a 2-day interval (rest). There are five dose levels: 50, 100, 165, 250, and 350 mg/m2. Secondary endpoints include pharmacokinetic (PK) parameters, rate of adverse events, progression-free survival (PFS), overall survival (OS), and objective response rate. All patients received alofanib until disease progression or unacceptable toxicity. As of data cutoff on December 30, 2020, 13 patients have been enrolled in the trial. Patients were predominantly male (85%), 54% had 2 and more metastatic sites, including liver metastases (54%), and were heavily pretreated (60% received previous 3-6 lines of therapy). To date, all enrolled patients have been studied for safety and have not experienced any dose-limiting toxicities (DLTs) within the 28-day DLT-assessment window. Grade 3 or higher drug related adverse events have included raised ALT/AST at 50 mg/m2, diarrhea at 165 mg/m2, and hyponatremia at 350 mg/m2. 93% of patients had any grade adverse events. Most common Grade 1-2 adverse events included fatigue, diarrhea, nausea, anemia, thrombocytopenia, increased alkaline phosphatase, and reactions immediately after intravenous injections (facial flushing, dizziness, weakness, sweating, and sinus tachycardia). Grade 1 hyperphosphatemia was founded in 25% of cases. One patient discontinued treatment due to drug related Grade 3 uncontrolled diarrhea. Alofanib has demonstrated evidence of biologic activity in 12 patients in the first 4 dose levels evaluated to date. Disease control rate was 75% (1 durable partial response (13 months) at 50 mg/m2 and 8 stable diseases at 50-250 mg/m2). After a median follow-up of 4.5 months, the median PFS and OS was not reached. In conclusion, dosing up to 350 mg/m2 of alofanib was well tolerated, DLT and MTD were not reached. The early biologic activity of alofanib in the late-line treatment of metastatic gastric cancer is encouraging. In addition to the above, any updated safety, PK, and efficacy data will be presented at the time of the AACR meeting.

Citation Format: Ilya Tsimafeyeu, Galina Statsenko, Anastasia Mochalova, Natalia Trenina, Vyacheslav Kurakin, Natalia Besova, Kristina Novoselova, Natalia Abramova, Ekaterina Obarevich, Alina Kashanova, Margarita Suetina, Vladimir Moiseyenko, Mikhail Byakhov, Elena Artamonova, Liubov Vladimirova, Sergei Tjulandin. Preliminary data on a phase 1b, first-in-human study of the allosteric extracellular FGFR2 inhibitor alofanib in patients with refractory metastatic gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT113.

Metastasectomy in colorectal carcinoma (CRC) patients (pts) with mBRAF: Prospective database analysis

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Background: Role of metastasectomy in pts with mBRAF metastatic CRC is still controversial. We performed analysis of prospective multicentric database of pts with mBRAF mCRC to evaluate the efficacy of metastasectomy in such group of pts in the real clinical practice. Methods: We analyzed a database of pts with mCRC in 7 cancer clinics in Russia and chose pts with metastasectomy with different mutational status. The primary endpoints were disease free survival (DFS) and overall survival (OS), which were calculated from the time of metastasectomy. Analysis was performed with the SPSS v.20 software package. Results: The study included 126 pts: 26 pts with mBRAF, 57 pts with mRAS and 43 pts with wtRAS/BRAF. Pts with mBRAF more often had synchronous metastases (50%/19,3/11,6%, p<0,01), N2 status (38,5%/11%/19,6%, p=0,04). In mBRAF cohort all but 1 pt had V600 mutations; peritonectomy performed in 19,2%, liver resection – in 34,6%, lung resection, ovariectomy, metastasectomy in brain and retroperitoneal lymph nodes dissection with removal of the local relapse – over 11,5%; R0 resection was achieved in 88,5%. Median DFS was 7 months in mBRAF pts, 14 months in mRAS and not achieved in wtRAS/BRAF group treated (HR 2,1, 95%CI 1,5-3.1, p<0.01). Median OS was 26 months in mBRAF, 38 months in mRAS and not achieved in wtRAS/BRAF group (HR 1,5, 95%CI 1,0-2,4, p=0.06). Perioperative chemotherapy didn’t improve DFS in pts with mBRAF (HR 1,9, 95%CI 0,67-5,7, p=0,2). The best median DFS were in pts after ovariectomy – 10 months, the worst - after retroperitoneal lymph nodes dissection with removal of the local relapse – 2 months. Conclusions: Prognosis of pts with mBRAF after metastasectomy is worse than with other mutational phenotypes. However in selected cases metastasectomy might be considered in such aggressive mCRC.

Abstract PS5-38: Short course of preoperative tamoxifen in premenopausal breast cancer patients: Biomarker changes and survival

Background: Luminal HER2 negative breast cancer is a highly heterogeneous disease, which complicates the choice of optimal systemic treatment in early stage disease. It is known that in postmenopausal patients (pts) Ki67 level after short course of preoperative endocrine therapy (PET) correlates with survival in contrast to baseline level. We performed the trial of PET in premenopausal early stage breast cancer pts.Patients and methods: This is a non-randomized, open-label, single-arm, phase II study of short course of preoperative tamoxifen in premenopausal pts. Primary objective was a decline in Ki67 level below 10%, secondary objectives were biomarker changes and disease free survival. Between 2011 and 2017 74 pts with T1-2N0-1M0 ER+ HER2 negative breast cancer were included in the study, median age was 45 (range, 32-55), median baseline Ki67 30% (range, 5-96), median stromal TILs 5% (range, 0-40). All pts were treated with tamoxifen for 2-3 weeks before surgery. Median follow-up was 56 months (range, 29.6-124.3).Results: There was a statistically significant decline in Ki67 during the short course of endocrine therapy (p&lt;0,001), median Ki67 level after PET was 20% (range 3-75). Also we noticed significant decline in estrogen receptor (ER) expression level (p=0,001), but not in progesterone receptor (PR) expression. There was an increase in the level of stromal TILs (p=0.09). Baseline level of Ki67 and tumor grade had significant impact on decline in Ki67 below 10%. None of 28 pts with baseline Ki67&gt;30% had post-PET Ki67&lt;10% in comparison with 20,5% (9/44) with baseline Ki67 10-30%. No pts with baseline TILs≥20% had decline in Ki67 below 10%. Baseline level of Ki67 did not correlate with survival, 3-year DFS with baseline Ki67≤30 was 94,4%, Ki67&gt;30% - 92,6% (p=0.54). Also there was no difference in survival according to Ki67 level after the course of endocrine therapy: with post-PET Ki67&lt;10% 3-year DFS was 100% (none of pts was treated with chemotherapy), 10-30 – 92,4%, &gt;30 – 94,4% (p=0.61). We explain this with the changes in adjuvant treatment in pts with high (&gt;30%) level of Ki67 after endocrine therapy – all pts were receiving adjuvant chemotherapy and, what is more important, they also had ovarian suppression and tamoxifen has been changed to aromatase inhibitors (AI). Conclusion: to our knowledge this is the first study of the short course of PET in premenopausal pts. We demonstrated that post-PET Ki67 level can be used for individualization of adjuvant therapy (intensification with chemotherapy, ovarian suppression, AI in poor responders and avoiding of chemotherapy in good responders). Further prospective randomized trials are warranted.

Citation Format: Mona Frolova, Marina Stenina, Alexander Petrovsky, Olga Krohina, Sergei Tjulandin. Short course of preoperative tamoxifen in premenopausal breast cancer patients: Biomarker changes and survival [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS5-38.

Is antiangiogenic therapy necessary for patients with metastatic colorectal cancer (mCRC) and mutation in the BRAF gene? Results of the systematic review and meta-analysis

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Background: There are no direct prospective randomized studies supporting the need for antiangiogenic drugs in the treatment of patients with the m BRAF mCRC. However, subgroup analysis of different studies showed conflicting results. Therefore, we performed systemic review and meta-analysis to compare efficacy anti-angiogenic targeted therapy with chemotherapy and chemotherapy alone in patients with m BRAF mCRC in terms of progression free survival (PFS), and overall survival (OS). Methods: We performed a search of all prospective randomized phase III studies in PubMed, ASCO and ESMO congresses for all years before September, 2020, compared chemotherapy (CT) plus bevacizumab or aflibercept or ramucirumab and CT alone at the first-line or second-lines with information of the BRAF status. Primary outcome was hazard ratio (HR) for PFS and 95% confidence interval (CI); secondary–HR for OS and 95%CI. Fixed effects were used for analysis. Meta-analysis was conducted by "Review Manager" Ver. 5.3. Results: We identified 4 trials (AVF2107g, AGITG MAX, VELOUR and RAISE), which included 120 patients with mBRAF (anti-angiogenic plus CT–65 (54%) and CT alone–55 (46%). According to results of the meta-analysis there was a tendency for significant improvement in PFS (HR 0.64, 95% CI 0.4-1.02; p = 0.06; I2 = 0%, p for heterogeneity 0.7; 53trials) and significant improvement in OS (HR 0.51, 95% CI 0.32-0.82; p = 0.005; I2 = 0%, p for heterogeneity 0.52; 4 trials) in group of ani-angiogenic therapy. Conclusions: Addition of anti-angiogenic therapy to chemotherapy showed improvement in the PFS and OS in pts with m BRAF compared with chemotherapy alone. A prospective randomized trial is needed to determine the optimal regimen of systemic therapy for pts with m BRAF mCRC.

Phase III, Randomized Study of Dual Human Epidermal Growth Factor Receptor 2 (HER2) Blockade With Lapatinib Plus Trastuzumab in Combination With an Aromatase Inhibitor in Postmenopausal Women With HER2-Positive, Hormone Receptor–Positive Metastatic Breast Cancer: Updated Results of ALTERNATIVE

PURPOSE

Human epidermal growth factor receptor 2 (HER2) targeting plus endocrine therapy (ET) improved clinical benefit in HER2-positive, hormone receptor (HR)–positive metastatic breast cancer (MBC) versus ET alone. Dual HER2 blockade enhances clinical benefit versus single HER2 blockade. The ALTERNATIVE study evaluated the efficacy and safety of dual HER2 blockade plus aromatase inhibitor (AI) in postmenopausal women with HER2-positive/HR-positive MBC who received prior ET and prior neo(adjuvant)/first-line trastuzumab (TRAS) plus chemotherapy. This updated article reflects minor numerical corrections in some secondary efficacy analyses that resulted from programming errors and that do not change the major conclusions of the study.

METHODS

Patients were randomly assigned (1:1:1) to receive lapatinib (LAP) plus TRAS plus AI, TRAS plus AI, or LAP plus AI. Patients for whom chemotherapy was intended were excluded. The primary end point was progression-free survival (PFS; investigator assessed) with LAP plus TRAS plus AI versus TRAS plus AI. Secondary end points were PFS (comparison of other arms), overall survival (OS), overall response rate (ORR), clinical benefit rate (CBR), and safety.

RESULTS

Three hundred fifty-five patients were included in this analysis: LAP plus TRAS plus AI (n = 120), TRAS plus AI (n = 117), and LAP plus AI (n = 118). Baseline characteristics were balanced. The study met its primary end point; superior PFS was observed with LAP plus TRAS plus AI versus TRAS plus AI (median PFS, 11 v 5.6 months; hazard ratio, 0.62 [95% CI, 0.45 to 0.88]; P = .0063). A consistent PFS benefit was observed in predefined subgroups. ORR, CBR, and OS also favored LAP plus TRAS plus AI. The median PFS with LAP plus AI versus TRAS plus AI was 8.3 versus 5.6 months (hazard ratio, 0.85 [95% CI, 0.62 to 1.17]; P = .3159). Common adverse events (AEs; ≥ 15%) with LAP plus TRAS plus AI, TRAS plus AI, and LAP plus AI were diarrhea (69%, 9%, and 51%, respectively), rash (36%, 2%, and 28%, respectively), nausea (22%, 9%, and 22%, respectively), and paronychia (30%, 0%, and 15%, respectively), mostly grade 1 or 2. Serious AEs were reported similarly across the 3 groups, and AEs leading to discontinuation were lower with LAP plus TRAS plus AI.

CONCLUSION

Dual HER2 blockade with LAP plus TRAS plus AI showed superior PFS benefit versus TRAS plus AI in patients with HER2-positive/HR-positive MBC. This combination offers an effective and safe chemotherapy-sparing alternative treatment regimen for this patient population.

Frequency of S492R mutations in the epidermal growth factor receptor: analysis of plasma DNA from patients with metastatic colorectal cancer treated with panitumumab or cetuximab monotherapy

Background

Antibodies against epidermal growth factor receptor (EGFR), panitumumab, a fully human monoclonal antibody, and cetuximab, a human/mouse chimeric monoclonal antibody, have shown clinical efficacy in metastatic colorectal cancer (mCRC). In the phase 3 noninferiority ASPECCT (ClinicalTrials.gov, NCT01001377) study, panitumumab was demonstrated to be noninferior to cetuximab and provided a similar overall survival benefit for patients with chemotherapy-refractory wild-type KRAS exon 2 mCRC. However, some patients eventually develop resistance to anti-EGFR therapy. EGFR p.S492R mutation was previously identified as conferring resistance to cetuximab, but not to panitumumab.

Methods

This biomarker study analyzed plasma samples from ASPECCT collected at both baseline and posttreatment.

Results

No EGFR p.S492R mutations were identified at baseline; however, after treatment the EGFR p.S492R mutation was detected in 1% of patients treated with panitumumab versus 16% of those treated with cetuximab, supporting that, in a large population, this mutation is more likely to be induced by cetuximab than by panitumumab. There were, however, no significant differences in progression-free survival or overall survival between patients who were wild-type compared with those with the S492R mutation within the cetuximab arm or the overall population.

Conclusions

These results may support targeting treatment to small patient subgroups based on the presence of emerging EGFR mutations and provide a molecular rationale for rechallenging with a different anti-EGFR agent in patients who develop resistance. Prospective studies are needed to evaluate the efficacy of panitumumab in the EGFR p.S492R mutant population.

Efficacy of platinum-based chemotherapy and prognosis of patients with pancreatic cancer with homologous recombination deficiency: comparative analysis of published clinical studies

The aim of our study was to determine the effect of homologous recombination deficiency (HRD) on prognosis and efficacy of platinum-based chemotherapy in patients with pancreatic cancer (PC). We performed PubMed and Embase database queries. We included 4 studies into the meta-analysis and 16 studies in the systematic review. Our systematic analysis showed that the average weighted median overall survival (OS) in patients with HRD with advanced PC was 19.8 and 15.6 months in patients without HRD. With platinum-based chemotherapy, the average weighted median OS in patients with HRD was 23.8 and 17.1 months in patients without HRD. Without platinum-based chemotherapy, the average weighted median OS in patients with HRD was 8.3 and 12.0 months in patients without HRD. For resected PC, our meta-analysis demonstrated that HRD status did not affect the prognosis (HR 1.03, 95% CI 0.46 to 2.33), but results were rather heterogeneous (I2=83%, p=0.003). Our systematic analysis showed that the average weighted median OS in patients with HRD was 34.6 and 27.0 months in patients without HRD. With platinum-based chemotherapy, the average weighted median OS in patients with HRD was 46.1 and 36.3 months in patients without HRD. Without platinum-based chemotherapy, the average weighted median OS in patients with HRD was 24.2 and 42.9 months in patients without HRD. Results of our meta-analysis and systematic review support the idea of platinum use in patients with HRD both in resected and metastatic PCs, although a randomised trial is warranted to make a more reliable conclusion. PROSPERO REGISTRATION NUMBER: CRD42019121914.

Overall Survival of Patients With ALK-Positive Metastatic Non-Small-Cell Lung Cancer in the Russian Federation: Nationwide Cohort Study

PURPOSE

The overall survival (OS) results in patients with ALK-positive metastatic non–small-cell lung cancer (NSCLC) have rarely been reported. The aim of this prospective-retrospective cohort study was to obtain real-world data on the use of crizotinib or chemotherapy in patients with ALK-positive metastatic NSCLC in Russia.

PATIENTS AND METHODS

Patients with epidermal growth factor receptor–negative metastatic NSCLC were screened in 23 cancer centers. To be eligible, patients were required to have confirmation of ALK rearrangement. Patients were treated with crizotinib (250 mg twice daily; n = 96) or the investigator’s choice of platinum-based chemotherapy (n = 53). The primary end point was OS.

RESULTS

A total of 149 ALK-positive patients were included. Mean age was 53 years in both groups. Patients were predominately women (59%) and never-smokers (74%), and most patients had adenocarcinoma histology (95%). At a median follow-up time of 15 months, 79 of the 149 patients included in the analysis had died. Median OS from the start of treatment was 31 months (95% CI, 28.5 to 33.5 months) in the crizotinib group and 15.0 months (95% CI, 9.0 to 21.0 months) in the chemotherapy group (P < .001). The objective response rate was 34% in the crizotinib group. Among patients with brain metastasis, one complete response (6%) and five partial responses (31%) were achieved. Grade 3 adverse events were observed in three patients (3%) in the crizotinib group.

CONCLUSION

The improved OS observed in crizotinib clinical trials in ALK-positive NSCLC was also observed in the less selective patient populations treated in daily practice in Russia. The use of standard chemotherapy in these patients remains common but seems inappropriate as a result of the effectiveness of newer treatments, such as crizotinib.

Efficacy of dose-dense chemotherapy as first-line treatment of advanced ovarian cancer patients after non-optimal debulking

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Background: Patients with advanced ovarian cancer have unfavorable prognosis after primary debulking surgery if the size of residual tumor exceeds 1 cm. The optimal approaches to systemic treatment of these patients remain unknown. We evaluated the efficacy and safety of dose-dose chemotherapy in frontline treatment of ovarian cancer patients after upfront non-optimal debulking surgery. Methods: This was a non-randomized single-arm phase II trial. We enrolled patients with advanced (FIGO III-IV) epithelial ovarian who underwent non-optimal upfront debulking surgery with residual tumor size > 10 mm. All patients were treated with dose-dense chemotherapy (ie, paclitaxel 80 mg/m2 day 1, 8, 15 + carboplatin AUC6 day 1, cycled every 21 days – 6 cycles). Patients in historical control arm received standard chemotherapy with paclitaxel 175 mg/m2 day 1 + carboplatin AUC6 day 1, cycled every 21 days – 6 cycles. No patient in experimental or control arm received front-line bevacizumab or PARP inhibitors. The primary endpoint of the trial was progression-free survival (PFS). According to the historical data of our department, 1-year PFS in this category of patients equals to 51%. To increase 1-year PFS to 70%, 40 patients should be enrolled with α = 0.05 and β = 0.20 and estimated data loss for 10% of patients. Results: The study enrolled 40 patients to dose-dense chemotherapy arm, control arm included 86 patients. The trial arms were balanced in terms of age, performance status and other characteristics. Median follow-up was 28.8 months. The 1-year PFS was 76.9% compared to 51% in historical arm, median PFS was 19.8 months and 12 months respectively (HR 0.61; 95% CI 0.39-0.95; p = 0,03). The 1-year overall survival rate was 92.3% with median OS not reached with specified follow-up period. Severe neutropenia, anemia, thrombocytopenia was observed in 82.1%, 53.8%, 15.3% of patients, respectively. Conclusions: The results of the study showed high efficacy of dose-dose chemotherapy as front line of treatment for advanced ovarian cancer patients after non-optimal upfront debulking surgery but one should consider high toxicity of this regimen.

Efficacy of platinum-based chemotherapy in platinum-resistant ovarian cancer: A systematic review with pooled analysis of outcomes

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Background: Current management of recurrent ovarian cancer (OC) is based on the amount of time between the completion of penultimate platinum-based treatment and the detection of relapse. Patients with platinum-free interval (PFI) < 6 mo. are considered to be platinum-resistant (PROC) and to have low response rate (RR) probability to platinum-based chemotherapy. Methods: We searched PubMed database for all prospective and retrospective full-text articles and abstracts on the treatment of patients with PROC for all years between 01/01/2000 and 01/06/2019 in English language. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) tool was used to ensure transparent reporting of the results. Study inclusion criteria were: 1) morphologically confirmed epithelial ovarian cancer; 2) standard definition of PROC as a disease that recurred within 6 months after completion of platinum-based chemotherapy; 3) treatment with platinum- or non-platinum chemotherapy with agents that are routinely used for OC; 4) no concomitant therapy with targeted or investigational agents; 5) clearly defined RR for patients with PROC and criteria used for response assessment. Pooled analysis of outcomes and multiple linear regression analysis was conducted to assess the impact of platinum salts on probability of response. Results: We identified 7156 articles and screened them for title and abstract. After the review process we selected 197 studies for further analysis. Of them, 52 (n = 1320) and 145 (n = 6937) trials assessed efficacy of platinum- and non-platinum based chemotherapy respectively. Among patients treated with platinum-based and non-platinum chemotherapy RR was 36.04% (95% CI 33.45-38.63) and 14.85% (95% CI 14.01-15.68) respectively. Pooled median progression-free survival was 5.8 mo. and 3.75 mo. respectively. In multiple linear regression model administration of platinum-based chemotherapy was the strongest predictor of objective response with B value 0.503 (p < 0.001). Among platinum agents cisplatin (RR 39.9%: 95% CI 35.8-44.0%) and carboplatin (RR 42.3%; 95% CI 37.0-47.6%) were associated with better rates of objective response compared to oxaliplatin (RR 28.1%; 95% CI 23.9-32.3). Conclusions: This systematic review shows that patients with 'platinum-resistant' ovarian carcinoma may derive significant benefit from reintroduction of platinum agents and their value should be evaluated in further randomized trials.

A prospective study of prognostic role of plasma circulating tumor DNA (ctDNA) in patients (pts) with early-stage malignancies

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Background: Recently, conflicting evidence has emerged showing the association of ctDNA level and cancer progression. The aim of our study was the development of a method for detecting ctDNA in plasma and the investigation of the prognostic value of ctDNA retention after surgery in the prospective way. Methods: This prospective, single-center, sample collection study; pts with early-stage malignancies of the different origin were included. Tumor somatic mutations were determined by target sequencing of DNA from FFPE tumor blocks. Sequencing was performed using the custom NGS panel covering regions of frequent somatic mutations in 50 genes. Tumor-specific mutations were monitored in plasma samples taken before and after surgery. The median time between surgery and plasma collection was 7 days (5-15). Mutations of plasma ctDNA were determined by ddPCR. The plasma sample was considered "positive" if the content of ctDNA was more than 0.5 copies of mutant DNA in ml plasma. We needed 265 pts for improving 1-year disease free survival (DFS) from 60% to 80% with α=0.01, β=0.1, 10% loss of f.-up and duration of the study for 2 years. Results: The study comprised 271 pts with various cancers including colorectal – 91 (33,6%), pancreatic – 37 (13,7%), breast – 66 (24,4%), lung – 35 (12,9%) and gastric cancer – 42 (15,5%). Pts with stage I was 50 (18,5%), stage II – 118 (43,5%) and stage III – 103 (38%). The median time of the f.-up was 9 mos. (1-37). No significant association was found between the level of ctDNA before surgery and DFS either in the general group or in groups stratified by tumor sites (HR 2.4, 95%CI 0.8-7.1, р=0.12 and HR 1.5, 95%CI 0.4-6.3, р=0.5, correspondingly). ctDNA was detected in the plasma after surgery in 57 (10%) pts: 9 (9.9%) cases of colorectal, 10 (27%) - pancreatic, 9 (13.6%) - breast, 19 (54.3%) - lung, and 10 (23.8%) - gastric cancer. Progression of the disease was detected in 28/57 (49%) pts with ctDNA(+) and 17/214 (8%) - in ctDNA(-) pts (p<0.001). One-year DFS in ctDNA(+) and ctDNA(-) pts were 57% and 87%, respectively (HR 6.1, 95%CI 3.3-11.2, p<0,001). ctDNA positivity after surgery was an independent negative prognostic factor according to Cox regression model fitted to T, N, and adjuvant chemotherapy (HR 5.7, 95%CI 3.1-10.8, p <0.001). Conclusions: These results demonstrate the prognostic significance of ctDNA persisting after surgery in pts with the early stage of the different malignancies. Further clinical validation of this approach is required in trails with modifications of the adjuvant treatment, according to the content of ctDNA.

Results of a completed first-in-human phase Ib dose-escalation study of oral CBL0137 in patients with advanced solid tumors

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Background: Curaxin CBL0137 is a novel compound with broad anticancer activity in animal models. The drug is a non-genotoxic DNA intercalator that interferes with histone/DNA binding causing decondensation of chromatin in tumor cells, functional inactivation of histone chaperone FACT, activation of p53 and IFN responses, and inhibition of pro-cancer transcriptional factors, MYC, NF-kB, HSF1, and HIF1a. Methods: The study enrolled adults with advanced chemorefractory solid tumors, ECOG PS ≤2, and adequate organ function. The primary objective was to find the maximum tolerated dose (MTD) and recommended dosing regimen (RDR). Secondary objectives were to evaluate CBL0137 safety, pharmacokinetics, and efficacy. CBL1037 was given orally once daily (QD) for the first 14 days of repeated 28-day cycles. A 3+3 dose escalation determined the MTD, defined as the highest dose at which ≤1 of 6 pts had Cycle 1 dose-limiting toxicity (DLT). Pharmacokinetics were assessed on Days 1 and 13. Efficacy was evaluated every 8 weeks. Results: 60 pts were enrolled (females/males [n]: 42/18; median [range] age 56 [25-76] years; ECOG PS [n] 0/1/2: 8/49/3); cancer types [n]: ovarian cancer [15], colorectal cancer [14], breast cancer [11], others [20]) over 16 dose levels ranging from 4 mg to 200 mg QD. Durations of therapy ranged from 6 to 342 days. Three DLTs were observed: prolongation of QTc Gr 3 (88 mg QD), neutropenia/thrombocytopenia Gr 4 (200 mg QD), and LV dysfunction Gr 3 (200 mg QD). Dose-dependent nausea/vomiting was observed and was Gr 2-4 at 200 mg QD. Gr 1/2 photosensitization occurred in 11 subjects across doses from 48 to 200 mg QD but was successfully managed with sun protection and resulted in no dose modifications or discontinuations. On Day 1, mean (range) plasma CBL0137 Tmax values were 5.1 (1-10) hrs. Generally linear increases in AUC occurred with increasing CBL0137 dose. Mean (range) t1/2 values were 25.6 (0.3-166) hrs, with minor dose dependency. Mean (range) Day 13/Day 1 Ctrough ratios showed 3.6 (1.7-7.2)-fold accumulations. Disease control was registered in 11 pts who had stable disease (SD). Target lesion regressions up to 21% were documented in 4 patients with breast cancer (2), sarcoma (1), and ovarian cancer (1). Pts with breast cancer (1) and sarcoma (1) had SD for > 36 weeks. Conclusions: The Phase 2 RDR for oral CBL0137 was established as 180 mg QD x 14 days in 28-day cycles based on bone marrow and gastrointestinal DLTs at 200 mg QD. CBL0137 showed a manageable safety profile with efficacy signals. Further study as a component of combinations is planned. Clinical trial information: 847 .

Frequency of brain metastases in patients with locally advanced triple negative breast cancer after neoadjuvant platinum-based chemotherapy: Impact of BRCA1/2 mutations

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Background: patients with triple negative breast cancer has poor survival outcomes. Achievement of pathological complete response (pCR) after neoadjuvant chemotherapy can significantly improve survival of these patients, however some patients will relapse even after pCR. Methods: we reviewed prospectively-maintained outcomes database of N.N. Blokhin NMRCO. We extracted information about patients with locally advanced non-metastatic (stage IIIA-IIIC) triple negative breast cancer who were treated with neoadjuvant platinum based chemotherapy in 2014-2018 years. All included patients were tested for the presence of BRCA1/2 mutation with whole-exome next-generation sequencing or for “founder” hot-spot mutations. Results: we identified 80 patients who received neoadjuvant treatment with various platinum-based regimens. Pathological complete response rate was 62.5%. BRCA-mutations was found at 22 (27.5%) patients. Median follow-up time was 35.6 months (17.0 – 61.3). 2-year DFS was 77.3%, and 3-year DFS was 70.0%, there was significant differences in DFS in patients, who achieved and patients with residual tumor – 85,2% vs 64,3% (p=0,028). 2-year OS was 91%, 3-year OS was 78,5%. 18 patient had disease progression, the most common sites of disease progression were brain (9 [50.0%]), lungs (5 [27.8%]), 3 (16.7%) patients had locoregional relapses and 1 (5,6%) liver metastases. We separately analysed characteristics of patients with brain metastases (table). There were no significant differences in tumour pathologic response and patient age. All patients, who relapced after pCR, had brain metastases. We also found, that 7 of 9 patients with brain metastases had different BRCA mutations. Brain metastases developed in 40,9% (9/22) of patients with BRCA1 mutations and 3,4% (2/58) of patients with wild type BRCA1 (p<0,00001). Conclusions: BRCA1 mutation is significant prognostic factor for brain metastases development in locally advanced triple negative breast cancer. [Table: see text]

FGFR2 inhibition could suppress spermatogenesis

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Background: The incidence of cancer among the people of reproductive age is constantly increasing. Although FGF2/FGFR2 expression in the male reproductive tract has been reported, there is no evidence of the impact of FGFRs inhibitors on sperm function. Therefore, the objective of this large study was to determine the effects of alofanib, selective FGFR2 allosteric extracellular inhibitor on the regulation of sperm physiology using the rat and rabbit models. Methods: Two-hundred forty Sprague-Dawley rats and 30 Chinchilla white rabbits received alofanib (0–40.5 and 0–21.6 mg/kg/day, respectively) intravenously on a consecutive daily dosing schedule for six months. Eighty rats and 8 rabbits were in the control group. The subchronic study evaluated high doses (300 mg/kg/day) of alofanib for 2 months in 15 male rats. Necropsy was conducted following treatment/recovery periods, and histologic examinations were performed. Results: Animals were active. After injections of a dose equivalent to a human therapeutic dose during 6 months, most of the seminiferous tubules were empty, the elements of spermatogenesis were not classified, and altered primary spermatogonia and spermatocytes were distinguished in male rats. After injections of a five-fold dose, all seminiferous tubules were empty and expelled by a cylindrical epithelium. Very similar changes in sperm physiology were founded in rabbits. Most of the seminiferous tubules were blank, and some tubules contained eosinophilic amorphous masses. High doses of alofanib resulted in pronounced atrophy of the spermatogenic tubule epithelium. Multinucleated giant cells were observed in the lumen of a part of the tubules. There were no changes in untreated animals. Conclusions: FGFR2 inhibition led to the suppression of spermatogenesis. Male cancer patients should be informed of this potential adverse event before treatment with FGFR2 inhibitors.

A phase Ib study of alofanib, an allosteric FGFR2 inhibitor, in patients with advanced or metastatic gastric cancer

TPS466

Background: Fibroblast growth factor receptor 2 (FGFR2) is amplified or overexpressed in 3% to 61% of patients with gastric cancer and associated with a poor prognosis. Acquired mutations in FGFR2 develop resistance to multikinase inhibitors. Besides, resistance to monoclonal antibodies depends on the type of FGFR2 isoforms IIIc or IIIb expressed by cancer cells. Alofanib (RPT835) is a novel selective allosteric inhibitor of FGFR2. Alofanib could bind to the non-active site of FGFR2 extracellular domain and had an inhibitory effect on FGF2-induced phosphorylation of FRS2α. On preclinical models no severe organ and function test changes were observed. Based on these results, alofanib has advanced into clinical evaluation. Methods: RPT835GC1B is a Phase 1b study, being conducted in at least four sites in Russia, evaluating the safety and preliminary efficacy of alofanib in patients with advanced and metastatic gastric adenocarcinoma pretreated with ≥ 1 previous lines of therapy. This trial consists of two parts. The standard dose-escalation part (design 3+3) aims to establish the maximum tolerated dose (MTD) or recommended phase 2 dose (R2PD) as a primary endpoint. The first part of the study includes a 28-day period when alofanib is administered daily intravenously for 5-days followed by a 2-day interval (rest). There are five dose levels: 50, 100, 165, 250, and 350 mg/m2. The dose-expansion phase accrues additional 20 patients, where comprehensive information to be collected. Secondary endpoints include pharmacokinetic parameters, rate of adverse events, progression-free survival, overall survival, and objective response rate. All patients will receive alofanib until disease progression or unacceptable toxicity. FGFR2 amplification, fusion, and overexpression will be assessed as well. Clinical trial information: NCT04071184.

Radiotherapy for Hepatocellular Carcinoma in Russia: a Survey-Based Analysis of Current Practice and the Impact of an Educational Workshop on Clinical Expertise

Radiation therapy (RT) is an effective treatment modality for hepatocellular carcinoma (HCC), but globally, it is underutilized. In Russia, practice patterns with regard to liver-directed radiation are unknown. Under the auspices of Russian Society of Clinical Oncology (RUSSCO), our team conducted an IRB-approved contouring workshop for Russian radiation oncologists. Pre- and post-workshop surveys were analyzed to determine baseline clinical experience and patterns of care for liver-directed RT among Russian providers. The effect of the contouring workshop on participants' knowledge was tested using mixed effects model. Forty pre-workshop and 24 post-workshop questionnaires were analyzable with a 100% response rate. Sixty percent of respondents had never evaluated a patient with HCC and only 8% (3 out of 40) reported treating an HCC patient with liver-directed RT. Nonetheless, 73% of respondents were comfortable offering liver-directed RT prior to the workshop. After the workshop, 85% of respondents felt comfortable treating a patient with HCC with liver-directed RT and 50% were comfortable recommending stereotactic body radiation therapy (SBRT). Measures of knowledge pertaining to evaluation of HCC patients and selection for appropriate liver-directed therapies were dramatically improved after the workshop. Liver-directed RT is not commonly used in Russia in the management of patients with HCC, and few centers are equipped for motion management. Our contouring workshop resulted in dramatically improved understanding of the evaluation and management of HCC patients. We recommend starting with a more protracted fractionated RT and building experience through attendance of additional educational activities, participation in multidisciplinary liver tumor boards, and prospective analysis of treatment toxicity and outcomes.

Started dose of regorafenib and overall survival (OS) in patients (pts) with metastatic colorectal cancer (mCRC): A systematic review and meta-analysis

131

Background: Regorafenib is one of the standards of care in pts with chemorefractory mCRC. However, high toxicity is a common reason of treatment discontinuation, interruption and dose reduction. There are conflicting results how started dose of regorafenib influence OS (REBECCA, ReDOS and ARRANGE trials). Therefore, we performed systemic review and meta-analysis to evaluate association between started dose of regorafenib and OS in pts with mCRC. Methods: We performed a search of all retrospective and prospective studies in PubMed, Embase, and Cochrane library. The search criteria included all articles and abstracts for all years before 20.08.2019. We compared the pts with standard dose (160 mg) and <160 mg at the first cycle. Primary outcome was hazard ratio (HR) for OS and 95% confidence interval (CI). Random effects were used for analysis due to potential heterogeneity of the studies. Meta-analysis was conducted by "Review Manager" Ver. 5.3. Results: We identified 6 trials – 3 prospective and 3 retrospective ones, which included 1955 pts (160 mg – 1584 and <160 mg – 571 pts). Two trials showed worsening OS in pts with dose <160 mg (Adenis et al., 2016 – HR 1.26, 95%CI 1.01-1.56 and Aljubran et al., 2019 – HR 2.25, 95%CI 0.93-5.43). Two studies showed improving OS in pts with dose <160 mg (Bekaii-Saab et al., 2018 – HR 0.72, 95%CI 0.47-1.11; Gotfrit et al., 2017 – HR 0.46, 95%CI 0.17-1.22). And two studies didn’t show any difference (Yamaguchi et al., HR 0.95, 95%CI 0.82-1.1 and Argiles et al., 2019 - HR 0.86, 95%CI 0.65-1.13). According to results of the meta-analysis there was not any difference in OS between groups with the dose 160 mg and <160 mg at the first cycle: HR 0.97, 95% CI 0.78-1.21; p = 0.79; I2 = 64. Conclusions: Started dose of regorafenib <160 mg in the pts with chemorefractory mCRC does not worsen the OS and this approach can be safely used in the daily clinical practice.

Bridging the Gap in Global Advanced Radiation Oncology Training: Impact of a Web-Based Open-Access Interactive Three-Dimensional Contouring Atlas on Radiation Oncologist Practice in Russia

Radiation oncologists in Russia face a number of unique professional difficulties including lack of standardized training and continuing medical education. To combat this, under the auspices of the Russian Society of Clinical Oncology (RUSSCO), our group has developed a series of ongoing in-person interactive contouring workshops that are held during the major Russian oncology conferences in Moscow, Russia. Since November 2016 during each workshop, we utilized a web-based open-access interactive three-dimensional contouring atlas as part of our didactics. We sought to determine the impact of this resource on radiation oncology practice in Russia. We distributed an IRB-approved web-based survey to 172 practicing radiation oncologists in Russia. We inquired about practice demographics, RUSSCO contouring workshop attendance, and the clinical use of open-access English language interactive contouring atlas (eContour). The survey remained open for 2 months until November 2017. Eighty radiation oncologists completed the survey with a 46.5% response rate. Mean number of years in practice was 13.7. Sixty respondents (75%) attended at least one RUSSCO contouring workshop. Of those who were aware of eContour, 76% were introduced during a RUSSCO contouring workshop, and 81% continue to use it in their daily practice. The greatest obstacles to using the program were language barrier (51%) and internet access (38%). Nearly 90% reported their contouring practices changed since they started using the program, particularly for delineation of clinical target volumes (57%) and/or organs at risk (46%). More than 97% found the clinical pearls/links to cooperative group protocols in the software helpful in their daily practice. The majority used the contouring program several times per month (43%) or several times per week (41%). Face-to-face contouring instruction in combination with open-access web-based interactive contouring resource had a meaningful impact on perceived quality of radiation oncology contours among Russian practitioners and has the potential to have applications worldwide.

Creation and development of the National Cancer Control Plan in Russia

10524

Background: The absence of the National Cancer Control Plan (NCCP) did not allow to develop оncology in Russia. Methods: Since 2015 experts of the N.N. Blokhin Russian National Comprehancive Center and Russian Oncology Association has initiated the creation of a National Anti-Cancer Strategy. Results: In 2016, the working group presented the first version of this Strategy to the professional community for wide discussion, which was transferred to the Russian Ministry of Health after a broad discussion in 2017. This strategy included prevention, screening, early diagnosis, treatment, rehabilitation and palliative care in patients with malignant tumors. In parallel, we created National Clinical Cancer Guidelines, which were approved by the professional community, and then we submited them to the Ministry of Health in 2017. Also in the period of 2017-2018, updated principles of creating clinical and statistical groups (CSG) were developed based on the calculation of the real costs of each type of surgery, radiation therapy and drug treatment. More than 1,000 different standards we established for each case of hospitalization and their cost has been calculated. Then, based on these calculations, we ranked four types of treatment (surgery, radiation therapy, chemotherapy and chemoradiation), each of which has 3, 5, 10 and 6 levels, respectively. These calculations formed the basis of the NCCP approved by the Government and the President starting from 2019 with an unprecedented additional level of funding of almost 1 trillion rubles (an increase of almost two times). The major goal of the Russian NCCP is to decrease mortality level from 202 to 185 (8,5%) per 100 000 population by the year of 2024. Conclusions: The еffort of the professional community with due consideration and consolidation with the Ministry of Health allows implementation of the NCCP on a national level.

Non-interventional study OVATAR final report: Diagnostic and treatment approaches in Russian ovarian cancer population—BRCAm group analysis

e13111

Background: First large Russian ovarian cancer observational study was conducted in 2014-2018. Methods: A total of 500 patients in 29 sites in Russia with newly diagnosed ovarian, peritoneal and fallopian tube cancer was enrolled (NCT02122588). The primary objective was to describe treatment approaches in the first line treatment. 141 patients (pts) with BRCA1/2 mutations (BRCA1/2mt) detected by NGS in blood and tissue were observed prospectively during at least 2 years. Results: Rate of BRCA1/2 mutations in Russian population is high – 28.4% (141 from 496 available for any testing). 77.6% (388/500) underwent biomarkers blood testing prior to treatment. CA-125 was positive in 99.7% (387/388), 15.2% (59/388) of pts had positive CA19-9, CA72-4 - in 2.3% (9/388). Positive CEA was presented in 15.2% (59/388). This marker was detected more frequently in BRCA2mt pts subgroup (28.0% (7/25)) than in BRCA1mt pts: 9.0% (8/90) (p = 0.05). 26.6% (133/500) of all study population had an oncology family history; 44.0% (62/141) BRCA1/2mt pts had relatives with oncological diseases and 19.7% (70/355) in BRCA wild type pts (p = 0.0001). 98.6% (139/141) of BRCA1/2mt pts received first line therapy. Objective response rate was registered in 79.8% (111/139) pts. Progression after platinum based regimens was observed in 53.6% (59/110) BRCA1mt pts and 44.8% (13/29) BRCA2mt pts. 35.6 % (21/59) of BRCA1mt pts had platinum-refractory and platinum-resistant relapses, while 15.4% in BRCA2mt subgroup (2/13) (p = 0.64). Platinum-sensitive relapses were in 64.4% (38/59) BRCA1mt pts and 84.6% BRCA2mt (11/13) (p = 0,64). Median PFS in BRCA1/2mt pts was 25.5 months. Among BRCA1/2mt pts underwent cytoreduction median PFS in subgroup without visible residual tumor was 36.4 months and in subgroup with residual tumor < 1 cm 15.3 months. Conclusions: In this large-scale prospective non-interventional study diagnostics and treatment approaches in Russian ovarian cancer pts were evaluated and high frequency of BRCA1/2mt was observed. Pts with BRCA1/2mt had better prognosis and most of them had platinum-sensitive relapses after first line chemotherapy that allowed platinum-based regimen rechallenge.

Management of muscle-invasive bladder cancer with bladder preservation in Russia: A survey-based analysis of current practice and the impact of an educational workshop on clinical expertise

10509

Background: Trimodality bladder preservation (BP) is an accepted alternative to radical cystectomy for patients with muscle-invasive bladder cancer (MIBC). The global utilization of BP is variable, and practice patterns have not been previously studied in Russia. During the Russian Annual Oncology Congress, organized by the Russian Society of Clinical Oncology in November 2018, our group has conducted a contouring workshop for Russian radiation oncologists (ROs). We sought to elucidate the contemporary practice patterns in Russia and determine the impact of this workshop on attitudes of Russian ROs towards BP. Methods: Pre- and post-workshop IRB-approved surveys were analyzed to determine baseline clinical experience and patterns of care among Russian ROs. The effect of the contouring workshop on participants’ knowledge and attitudes was performed using tests for paired nominal data. Results: We analyzed 77 pre-workshop and 32 matched post-workshop questionnaires. 56% (43 out of 77) of respondents treated MIBC patients with bladder-directed radiation therapy (RT). Of these, 40% (17 out of 43) treated only inoperable patients, and 60% treated both operable and inoperable MIBC patients. 14% offered RT alone to their patients, while the rest offered concurrent chemoRT. 63% (26 out of 41) offered suboptimal concurrent systemic agents, such as single agents carboplatin or paclitaxel. 63% of respondents felt that BP can only be done in specialized centers with established expertise, but only 10% felt uncomfortable offering an MIBC patient a BP option in their clinic. Prior to workshop, 40% of respondents estimated universal poor bladder and erectile functions after BP. The workshop resulted in dramatic change in participants’ attitudes towards BP long-term urinary (Stuart-Maxwell-test, p < 0.01), and sexual (exact McNemar test, p < 0.01) side-effects. Prior to workshop, only 52% of respondents routinely discussed smoking cessation (SC) with their patients, whereas after workshop almost 90% agreed that SC discussion is mandatory (exact McNemar test, p = 0.04). Conclusions: Bladder preservation is commonly used in Russia in the management of MIBC patients. Our contouring workshop resulted in dramatically improved understanding of long-term BP toxicities and inspired Russian ROs to incorporate smoking cessation counseling into routine clinical practice. International educational efforts are critical to improve multi-disciplinary management of MIBC patients.