Thalidomide consolidation improves progression-free survival in myeloma with normal but not up-regulated expression of fibroblast growth factor receptor 3: analysis from the Australasian Leukaemia and Lymphoma Group MM6 clinical trial

Machine Learning Applicability for Classification of PAD/VCD Chemotherapy Response Using 53 Multiple Myeloma RNA Sequencing Profiles

Multiple myeloma (MM) affects ~500,000 people and results in ~100,000 deaths annually, being currently considered treatable but incurable. There are several MM chemotherapy treatment regimens, among which eleven include bortezomib, a proteasome-targeted drug. MM patients respond differently to bortezomib, and new prognostic biomarkers are needed to personalize treatments. However, there is a shortage of clinically annotated MM molecular data that could be used to establish novel molecular diagnostics. We report new RNA sequencing profiles for 53 MM patients annotated with responses on two similar chemotherapy regimens: bortezomib, doxorubicin, dexamethasone (PAD), and bortezomib, cyclophosphamide, dexamethasone (VCD), or with responses to their combinations. Fourteen patients received both PAD and VCD; six received only PAD, and 33 received only VCD. We compared profiles for the good and poor responders and found five genes commonly regulated here and in the previous datasets for other bortezomib regimens (all upregulated in the good responders): FGFR3, MAF, IGHA2, IGHV1-69, and GRB14. Four of these genes are linked with known immunoglobulin locus rearrangements. We then used five machine learning (ML) methods to build a classifier distinguishing good and poor responders for two cohorts: PAD + VCD (53 patients), and separately VCD (47 patients). We showed that the application of FloWPS dynamic data trimming was beneficial for all ML methods tested in both cohorts, and also in the previous MM bortezomib datasets. However, the ML models build for the different datasets did not allow cross-transferring, which can be due to different treatment regimens, experimental profiling methods, and MM heterogeneity.

Thalidomide and prednisolone versus prednisolone alone as consolidation therapy after autologous stem-cell transplantation in patients with newly diagnosed multiple myeloma: final analysis of the ALLG MM6 multicentre, open-label, randomised phase 3 study

BACKGROUND

We previously showed that consolidation therapy with thalidomide and prednisolone improved progression-free and overall survival in patients with multiple myeloma who had undergone autologous stem-cell transplantation. We aimed to assess whether these survival advantages were durable at 5 years.

METHODS

The ALLG MM6 trial was a multicentre, open-label, randomised phase 3 trial done between Jan 13, 2002, and March 15, 2005, at 29 sites in Australia and New Zealand. Patients with newly diagnosed multiple myeloma were randomly assigned (1:1), via computer-generated randomisation charts, to receive indefinite prednisolone maintenance alone (control group) or in combination with 12 months of thalidomide consolidation (thalidomide group) after autologous stem-cell transplantation. Randomisation was stratified by treating centre and pre-transplantation concentrations of β2 microglobulin. Patients and treating physicians were not masked to treatment allocation. Primary endpoints were progression-free survival and overall survival. Analysis was by intention to treat. Secondary endpoints were overall response to salvage therapy, incidence of second primary malignancy incidence, and cost-effectiveness. This trial is registered with the Australian and New Zealand Clinical Trials Registry, number ACTRN12607000382471.

FINDINGS

We randomly assigned 269 patients to the thalidomide (n=114) or control group (n=129). After a median follow-up of 5·4 years (IQR 3·1-7·2), estimated 5-year progression-free survival was 27% (95% CI 23-32) in the thalidomide group and 15% (11-18) in the control group (hazard ratio [HR] 0·16, 95% CI 0·044-0·58; p=0·0054) and 5-year overall survival was 66% (95% CI 61-70) and 47% (42-51), respectively (HR 0·12, 95% CI 0·028-0·56; p=0·0072). There was no difference in overall response to salvage therapy, survival post-progression, or incidence of secondary malignancies between the two groups. Incremental cost-effectiveness ratio was AUS$26 996 per mean life-year gained.

INTERPRETATION

Consolidation therapy with thalidomide and prednisolone after autologous stem-cell transplantaion is an acceptable therapeutic approach when alternative drugs are not available.

FUNDING

Pharmion Corporation, Novartis Pharmaceuticals, Amgen Australia, The Merrin Foundation, and Alfred Health.

FGFR3 overexpression is prognostic of adverse outcome for muscle-invasive bladder carcinoma treated with adjuvant chemotherapy

BACKGROUND

Alterations in fibroblast growth factor receptor 3 (FGFR3) have been implicated in the pathogenesis of urothelial carcinoma. However, its clinicopathological significance has not been clearly established, especially in muscle-invasive bladder cancer (MIBC).

OBJECTIVES

The aim of our study was to investigate the mutation and overexpression of FGFR3 in MIBC cases from radical cystectomy and to analyze the prognostic and predictive significance in the groups with or without adjuvant chemotherapy.

METHODS AND MATERIALS

Study cohorts included 72 cases of MIBC including 42 patients who were treated with adjuvant chemotherapy. The mutation status of FGFR3 exons 7, 10, and 15 was investigated and protein expression was evaluated. The findings were analyzed for the association with relevant clinicopathological findings.

RESULTS

FGFR3 mutations were found in 7 patients (9.7%) and were correlated with a pattern of papillary growth, moderate histologic grade (G2 vs. G3), and moderately advanced TNM stage (II-III vs. IV). FGFR3 protein overexpression was detected in 33 cases (45.8%) but was not associated with the relevant clinicopathological parameters. In patients treated with adjuvant chemotherapy, FGFR3 overexpression was correlated with shorter disease-free survival (P = 0.067, 95% confidence interval: 14.8-29.6, marginal significance) and overall survival (P = 0.035), remaining as a significant independent prognostic factor for disease-free survival and overall survival in multivariate analysis using Cox proportional hazards model. In patients without adjuvant chemotherapy, FGFR3 mutation or overexpression did not have prognostic significance in multivariate analysis.

CONCLUSION

We report the FGFR3 alterations in MIBCs, and discuss their biological implication in subsets of patients. FGFR3 overexpression was predictive of adverse outcome in patients with adjuvant cisplatin-based chemotherapy after radical cystectomy. The utility of FGFR3 as a therapeutic target is suggested.

Improving overall survival and overcoming adverse prognosis in the treatment of cytogenetically high-risk multiple myeloma

Multiple myeloma (MM) is a heterogeneous disease with certain genetic features [e.g., t(4;14), del17p] associated with worse outcome. The introduction of thalidomide, lenalidomide, and bortezomib has dramatically improved the outlook for patients with MM, but their relative benefit (or harm) for different genetic patient subgroups remains unclear. Unfortunately, the small number of patients in each subgroup frequently limits the analysis of high-risk patients enrolled in clinical trials. Strategies that result in survival of high-risk genetic subgroups approximating that of patients lacking high-risk features are said to overcome the poor prognostic impact of these high-risk features. This outcome has been difficult to achieve, and studies in this regard have so far been limited by inadequate sample size. In contrast, strategies that compare the survival of high-risk genetic subgroups randomized to different treatment arms can identify approaches that improve survival. This type of analysis is clinically useful, even if the absolute gains do not improve outcomes to levels seen in patients without high-risk cytogenetics. Reviewing available data in high-risk MM from this perspective, it appears that bortezomib has frequently been associated with improved survival, whereas thalidomide maintenance has sometimes been associated with a shorter survival.