Role of (F-18) Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Prediction of Response to Neoadjuvant Therapy in Esophageal Cancer: Correlation with Pathological Response and Survival.

Purpose: The purpose of this study is to assess the correlation between metabolic response with fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and pathological response in patients with locally advanced esophageal cancer treated with neoadjuvant chemoradiotherapy and to study FDG-PET parameters for the prediction of pathological response and outcome. Methods: Twenty-five patients with locally advanced esophageal cancer underwent two FDG-PET/CT scans for initial staging and after neoadjuvant chemoradiotherapy. FDG uptake in the primary tumor was calculated in both scans (SUVmax, SULpeak, and TLG). Metabolic response was assessed according to the reduction of PET parameters: complete response (mCR = 100%), partial response (mPR ≥50%), and no response (mNR ≤50%). Pathological response was also classified as complete (pCR), partial (pPR), or no response (pNR). Patients were followed up (range, 8-99 months) determining free-disease interval (FDI) and overall survival (OS). Results: Two patients were excluded due to exitus for nonesophageal-related causes. The metabolic response was observed in 18/23 remaining patients (3mCR, 15 mPR), of which 12/18 patients showed a pathological response (3 pCR, 9 pPR). A major discrepancy was observed in 2 mNR patients who achieved pPR. FDI and OS were longer in patients with metabolic response than nonresponders, but no statistical difference was found. No significant correlation was found between PET parameters and pathological response, FDI, and OS. Conclusions: FDG-PET/CT is a useful technique to assess response to neoadjuvant chemoradiotherapy in esophageal cancer. Although in this preliminary study, no correlation between metabolic and pathologic response was found and no statistical differences between responders and nonresponders were observed, a tendency of longer FDI and OS was apparently found in responders patients.

Final Results of Neoadjuvant Atezolizumab in Cisplatin-ineligible Patients with Muscle-invasive Urothelial Cancer of the Bladder.

BACKGROUND: Neoadjuvant immunotherapies hold promise in muscle-invasive bladder cancer (MIBC). OBJECTIVE: To report on 2-yr disease-free (DFS) and overall (OS) survival including novel tissue-based biomarkers and circulating tumor DNA (ctDNA) in the ABACUS trial. DESIGN, SETTING, AND PARTICIPANTS: ABACUS was a multicenter, single-arm, neoadjuvant, phase 2 trial, including patients with MIBC (T2-4aN0M0) who were ineligible for or refused neoadjuvant cisplatin-based chemotherapy. INTERVENTION: Two cycles of atezolizumab were given prior to radical cystectomy. Serial tissue and blood samples were collected. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoints of pathological complete response (pCR) rate and dynamic changes to T-cell biomarkers were published previously. Secondary outcomes were 2-yr DFS and OS. A biomarker analysis correlated with relapse-free survival (RFS) was performed, which includes FOXP3, major histocompatibility complex class I, CD8/CD39, and sequential ctDNA measurements. RESULTS AND LIMITATIONS: The median follow-up time was 25 mo (95% confidence interval [CI] 25-26). Ninety-five patients received at least one cycle of atezolizumab. Eight patients did not undergo cystectomy (only one due to disease progression). The pCR rate was 31% (27/88; 95% CI 21-41). Two-year DFS and OS were 68% (95% CI 58-76) and 77% (95% CI 68-85), respectively. Two-year DFS in patients achieving a pCR was 85% (95% CI 65-94). Baseline PD-L1 and tumor mutational burden did not correlate with RFS (hazard ratio [HR] 0.60 [95% CI 0.24-1.5], p = 0.26, and 0.72 [95% CI 0.31-1.7], p = 0.46, respectively). RFS correlated with high baseline stromal CD8+ (HR 0.25 [95% CI 0.09-0.68], p = 0.007) and high post-treatment fibroblast activation protein (HR 4.1 [95% CI 1.3-13], p = 0.01). Circulating tumor DNA positivity values at baseline, after neoadjuvant therapy, and after surgery were 63% (25/40), 47% (14/30), and 14% (five/36), respectively. The ctDNA status was highly prognostic at all time points. No relapses were observed in ctDNA-negative patients at baseline and after neoadjuvant therapy. The lack of randomization and exploratory nature of the biomarker analysis are limitations of this work. CONCLUSIONS: Neoadjuvant atezolizumab in MIBC is associated with clinical responses and high DFS. CD8+ expression and serial ctDNA levels correlated with outcomes, and may contribute to personalized therapy in the future. PATIENT SUMMARY: We showed that bladder cancer patients receiving immunotherapy followed by cystectomy have good long-term outcomes. Furthermore, we found that certain biological features can predict patients who might have particular benefit from this therapy.

Toxicity and Surgical Complication Rates of Neoadjuvant Atezolizumab in Patients with Muscle-invasive Bladder Cancer Undergoing Radical Cystectomy: Updated Safety Results from the ABACUS Trial.

BACKGROUND: There are limited data on toxicity and surgical safety associated with neoadjuvant programmed death ligand 1 (PD-L1) inhibitors prior to radical cystectomy (RC) in patients with muscle-invasive bladder cancer (MIBC). OBJECTIVE: To present a comprehensive safety analysis of the largest neoadjuvant series, with focus on timing and severity of toxicity and surgical complications occurring after neoadjuvant atezolizumab in patients with MIBC enrolled in the ABACUS trial. DESIGN, SETTING, AND PARTICIPANTS: ABACUS (NCT02662309) is an open-label, multicenter, phase II trial for patients with histologically confirmed (T2-T4aN0M0) MIBC, awaiting RC. Patients either were ineligible or refused cisplatin-based neoadjuvant chemotherapy. INTERVENTION: Two cycles of neoadjuvant atezolizumab (1200 mg, every 3 wk) followed by RC. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Description of atezolizumab toxicity profile in the neoadjuvant setting, impact on surgery, and delayed immune-mediated adverse events (AEs) were assessed. RESULTS AND LIMITATIONS: Ninety-five patients received treatment. Of them, 44% (42/95) had atezolizumab-related AEs during the neoadjuvant period (fatigue [20%], decreased appetite [6%], and transaminases increased [6%]). Treatment-related grade 3-5 AEs occurred in 11% (10/95) of patients during the study. Of the patients, 21% (20/95) received only one cycle of atezolizumab due to AEs; 92% (87/95) underwent RC. No surgery was delayed due to atezolizumab-related toxicities. Surgical complications occurred in 62% (54/87) of patients. Of these patients, 43% (37/87) and 20% (17/87) had minor (grade 1-2) and major (grade 3-5) complications, respectively. Thirteen of 87 (15%) patients had post-RC atezolizumab-related AEs, including adrenal insufficiency and transaminases increased. Three deaths occurred during the period of study-related interventions (one non-treatment-related aspiration pneumonia, one immune-related myocardial infarction, and one cardiogenic shock after RC). Not all surgical safety parameters were available. CONCLUSIONS: Two cycles of neoadjuvant atezolizumab are well tolerated and do not seem to impact surgical complication rates. Owing to the long half-life, AEs may occur in the postoperative period, including endocrine abnormalities requiring attention and intervention. PATIENT SUMMARY: Here, we report a comprehensive dataset of patients receiving neoadjuvant immune checkpoint inhibitors before radical cystectomy. Treatment with neoadjuvant atezolizumab is safe and does not seem to complicate surgery significantly.

Final Overall Survival Analysis of the SOGUG Phase 2 MAJA Study: Maintenance Vinflunine Versus Best Supportive Care After First-Line Chemotherapy in Advanced Urothelial Carcinoma.

INTRODUCTION: The MAJA study compared vinflunine (VFL) plus best supportive care (BSC) maintenance therapy versus BSC alone in advanced urothelial carcinoma responsive to first-line chemotherapy. The primary end point of progression-free survival was achieved. We present the final overall survival (OS) and long-term follow-up safety analyses. PATIENTS AND METHODS: Patients were enrolled, and a subsequent post hoc analysis was performed on the basis of radiologic response or stabilization to first-line cisplatin/gemcitabine (CG) chemotherapy (4-6 cycles), according to Response Evaluation Criteria in Solid Tumors (RECIST). VFL + BSC versus BSC alone were randomly assigned until disease progression. RESULTS: At final analysis, 58 patients (66.7%) had died while 29 (33.3%) had survived; the BSC arm had higher mortality (VFL + BSC, n = 26, 59.1% vs. BSC, n = 32, 74.4%). Median follow-up of surviving patients was 38.8 months (interquartile range, 23.8-61.6). Median OS was 16.7 months (95% confidence interval, 0-34.5) in VFL and 13.2 months (95% confidence interval, 6-20.4) in the BSC groups (hazard ratio, 0.736; 95% confidence interval, 0.44-1.24, P = .182). Post hoc group division did not affect median OS in either study arm. CONCLUSION: Final analysis supported a benefit of VFL in maintenance therapy in patients with disease control after first-line treatment with CG, with no unexpected long-term adverse effects. The study was insufficiently powered to show a significant OS advantage.

Publisher Correction: Clinical efficacy and biomarker analysis of neoadjuvant atezolizumab in operable urothelial carcinoma in the ABACUS trial.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Clinical efficacy and biomarker analysis of neoadjuvant atezolizumab in operable urothelial carcinoma in the ABACUS trial.

Antibodies targeting PD-1 or its ligand 1 PD-L1 such as atezolizumab, have great efficacy in a proportion of metastatic urothelial cancers1,2. Biomarkers may facilitate identification of these responding tumors3. Neoadjuvant use of these agents is associated with pathological complete response in a spectrum of tumors, including urothelial cancer4-7. Sequential tissue sampling from these studies allowed for detailed on-treatment biomarker analysis. Here, we present a single-arm phase 2 study, investigating two cycles of atezolizumab before cystectomy in 95 patients with muscle-invasive urothelial cancer (ClinicalTrials.gov identifier: NCT02662309). Pathological complete response was the primary endpoint. Secondary endpoints focused on safety, relapse-free survival and biomarker analysis. The pathological complete response rate was 31% (95% confidence interval: 21-41%), achieving the primary efficacy endpoint. Baseline biomarkers showed that the presence of preexisting activated T cells was more prominent than expected and correlated with outcome. Other established biomarkers, such as tumor mutational burden, did not predict outcome, differentiating this from the metastatic setting. Dynamic changes to gene expression signatures and protein biomarkers occurred with therapy, whereas changes in DNA alterations with treatment were uncommon. Responding tumors showed predominant expression of genes related to tissue repair after treatment, making tumor biomarker interpretation challenging in this group. Stromal factors such as transforming growth factor-ß and fibroblast activation protein were linked to resistance, as was high expression of cell cycle gene signatures after treatment.