Using non-randomized trials to assess the clinical benefit of systemic anti-cancer treatments: Viable or not?

BACKGROUND: The Dutch Committee for the Evaluation of Oncological Agents (cieBOM) assesses the clinical benefit of systemic anti-cancer treatments (SACTs). For SACTs tested in non-randomized trials (NRTs), cieBOM primarily utilizes response-related thresholds as assessment criteria. As sufficiency of NRT-based evidence for benefit assessments is questionable, this study investigated whether and how NRTs can be used to assess the clinical benefit of new SACTs initially appraised by cieBOM based on randomized controlled trials (RCTs). METHODS: Using the RCTs underpinning cieBOM recommendations issued between 2015 and 2017, we searched for matching NRTs and applied the NRT-related assessment criteria by cieBOM to them. We then compared the assessment outcomes to the respective RCT-based cieBOM recommendations. Further, we investigated how the assessments would change when applying different response-related thresholds and adding a progression-free survival (PFS) threshold. RESULTS: For 13 of the 37 eligible recommendations, a matching NRT was found. Two treatments were assessed positively and six negatively; five treatments were non-assessable. Two positive recommendations matched a positive NRT-based assessment; one matching negative assessment was found, and one treatment could not be assessed based on either trial results. Adding a > 6 months PFS threshold decreased the number of non-assessable NRTs (five to two). CONCLUSIONS: Limited publications and inconsistent data reporting hampered the viability of NRTs for clinical benefit assessments of SACTs beyond the scope of rare indications. Further, response-related assessment criteria alone might not fully grasp the clinical benefit of novel SACTs. NRT-based assessments should be considered with caution due to uncertainty of the trial results.

A comparison of carboplatin and paclitaxel with cisplatinum and 5-fluorouracil in definitive chemoradiation in esophageal cancer patients.

BACKGROUND: In esophageal cancer (EC) patients who are not eligible for surgery, definitive chemoradiation (dCRT) with curative intent using cisplatinum with 5-fluorouracil (5-FU) is the standard chemotherapy regimen. Nowadays carboplatin/paclitaxel is also often used. In this study, we compared survival and toxicity rates between both regimens. PATIENTS AND METHODS: This multicenter study included 102 patients treated in five centers in the Northeast Netherlands from 1996 till 2008. Forty-seven patients received cisplatinum/5-FU (75 mg/m(2) and 1 g/m(2)) and 55 patients carboplatin/paclitaxel (AUC2 and 50 mg/m(2)). RESULTS: Overall survival (OS) was not different between the cisplatinum/5-FU and carboplatin/paclitaxel group {[P = 0.879, hazard ratio (HR) 0.97 [confidence interval (CI) 0.62-1.51]}, with a median survival of 16.1 (CI 11.8-20.5) and 13.8 months (CI 10.8-16.9). Median disease-free survival (DFS) was comparable [P = 0.760, HR 0.93 (CI 0.60-1.45)] between the cisplatinum/5-FU group [11.1 months (CI 6.9-15.3)] and the carboplatin/paclitaxel group [9.7 months (CI 5.1-14.4)]. Groups were comparable except clinical T stage was higher in the carboplatin/paclitaxel group (P = 0.008). High clinical T stage (cT4) was not related to OS and DFS in a univariate analysis (P = 0.250 and P = 0.201). A higher percentage of patients completed the carboplatin/paclitaxel regimen (82% versus 57%, P = 0.010). Hematological and nonhematological toxicity (≥grade 3) in the carboplatin/paclitaxel group (4% and 18%) was significantly lower than in the cisplatinum/5-FU (19% and 38%, P = 0.001). CONCLUSIONS: In this study, we showed comparable outcome, in terms of DFS and OS for carboplatin/paclitaxel compared with cisplatinum/5-FU as dCRT treatment in EC patients. Toxicity rates were lower in the carboplatin/paclitaxel group together with higher treatment compliance. Carboplatin/paclitaxel as an alternative treatment of cisplatinum/5-FU is a good candidate regimen for further evaluation.

The in- or exclusion of non-breast cancer related death and contralateral breast cancer significantly affects estimated outcome probability in early breast cancer.

A wide variation of definitions of recurrent disease and survival are used in the analyses of outcome of patients with early breast cancer. Explicit definitions with details both on endpoints and censoring are provided in less than half of published studies. We evaluated the effects of various definitions of survival and recurrent disease on estimated outcome in a prospectively determined cohort of 463 patients with primary breast cancer. Outcome estimates were determined both by the Kaplan-Meier and a competing risk method. In- or exclusion of contralateral breast cancer or non-disease related death in the definition of recurrent disease or survival significantly affects estimated outcome probability. The magnitude of this finding was dependent on patient-, tumour-, and treatment characteristics. Knowledge of the contribution of non-disease related death or contralateral breast cancer to estimated recurrent disease rate and overall death rate is indispensable for a correct interpretation and comparison of outcome analyses.

Prognostic value of mitotic counts in axillary node negative breast cancer patients with predominantly well-differentiated tumours.

AIMS: In axillary node negative (ANN) breast cancer patients additional prognostic markers are needed to decide whether adjuvant systemic treatment might be useful. METHODS: In the present study, the prognostic relevance of mitotic counts and Bloom-Richardson grade (BR-grade) was evaluated in 164 ANN breast cancer patients. No adjuvant systemic treatment was given to any of these patients. Mitotic counts were determined twice, in routine practice and in revision. RESULTS: A substantial reproducibility of mitotic counts was found, provided that the cut-off value chosen was high enough. After a median follow-up of 10 years, mitotic counts had no prognostic significance for survival at any cut-off value. A trend towards a significant worse survival was found for patients with Bloom-Richardson grade II or III in comparison with grade I. CONCLUSIONS: Based on data in the literature a positive association between both mitotic counts and BR-grade and survival in ANN breast cancer may exist, but the extent of this putative association and its clinical relevance can be argued, particularly in a group of patients with predominantly well differentiated tumours.

[Acetylsalicylic acid for the primary prevention of cardiovascular disease in diabetic patients]. / Acetylsalicylzuur bij patiëten met diabetes voor de primaire preventie van cardiovasculaire aandoeningen.

Large-scale trials have shown that primary prevention using acetylsalicylic acid is useful in all patients with a cardiovascular risk exceeding 1.5% annually. In these patients the benefits of prevention outweigh the risks of bleeding. Almost all patients with diabetes mellitus are at high risk of developing cardiovascular disease. Additionally, most diabetics have other cardiovascular risks besides diabetes, providing further argument for prevention with acetylsalicylic acid. Only very few prospective trials have confirmed that acetylsalicylic acid treatment in patients with diabetes mellitus reduces their risk of cardiovascular disease and myocardial infarction. Treatment with acetylsalicylic acid should be considered in all patients with diabetes, especially in view of their decreased survival after a cardiovascular event, myocardial infarction in particular. If acetylsalicylic acid is contra-indicated treatment with clopidogrel is an alternative.

Acute toxicity of concurrent adjuvant radiotherapy and chemotherapy (CMF or AC) in breast cancer patients. a prospective, comparative, non-randomised study.

The concurrent administration of adjuvant chemotherapy and radiotherapy in breast cancer treatment might lead to an increased incidence of side-effects. In this prospective, non-randomised, comparative study, the acute toxicity of radiotherapy alone (RT) and radiotherapy concurrent with doxorubicin-cyclophosphamide (AC/RT) and radiotherapy concurrent with cyclophosphamide-methotrexate-5-fluorouracil (CMF/RT) was compared. We used the common toxicity criteria (CTC) to score the level of acute toxicity before, during and 6 months after the completion of the period of irradiation. The number of hospital admissions, as well as the compliance of chemotherapy, were noted. We observed that patients treated with AC/RT and CMF/RT had significant higher incidences of (high-grade) skin-toxicity, oesophagitis, dyspnoea, malaise, anorexia, nausea and hospital admission compared with those treated with RT only. The target-volume of radiotherapy was the main predictor of (high-grade) acute skin toxicity and oesophagitis. AC/RT was associated with significant more (high-grade) skin toxicity than CMF/RT. The dose of chemotherapy was reduced to less than 85% of the planned dose in 11% of patients, 17% of patients treated with concurrent chemotherapy and radiotherapy needed admission to hospital. From the results of our study, we conclude that the concurrent administration of adjuvant chemotherapy and radiotherapy leads to an unacceptably high level of acute toxicity.

The prognostic value of hormone receptor detection by enzyme immunoassay and immunohistochemistry: a prospective study in patients with early breast cancer.

The main reason to determine estrogen (ER) and progesterone receptors (PR) in breast cancer is their predictive value for the response to endocrine therapy. In addition, ER and PR are often used as prognostic indicators. Enzyme immunoassay (EIA) and immunocytochemical assay (ICA) are two methods for determining ER and PR. These two methods have not been compared with each other in relation to clinical endpoints. In the present study we prospectively evaluated the prognostic value of ER and PR as determined by ICA and EIA in 223 and 207 patients, respectively, with early breast cancer. ER was positive in approximately 77% of patients, while PR was positive in approximately 65% of patients. The proportion of potential agreement beyond chance between EIA and ICA was 0.58 and 0.65 for ER and PR, respectively. The median follow-up was 86 months. Both ER and PR appeared to be weak prognostic factors. There were no differences in prognostic value according to the time point of analysis or cutoff value chosen, nor were there any differences in the prognostic value of hormone receptors detected by ICA or EIA. Both methods appear to be equivalent in terms of qualification and prognostic value.