You will be presented with a collection of medical randomized controlled trial (RCT) reports addressing a shared clinical question -- for instance, the efficacy of a medical intervention on a disease or condition. Given the titles and abstracts of these reports, your task is to generate the conclusion of the systematic review article synthesizing the key findings. Your conclusion should be a few sentences long. In your response, include only the conclusion and no other text. The RCT reports are below.



Title 1:
Experience of malignancies with oral glucose-lowering drugs in the randomised controlled ADOPT (A Diabetes Outcome Progression Trial) and RECORD (Rosiglitazone Evaluated for Cardiovascular Outcomes and Regulation of Glycaemia in Diabetes) clinical trials
Abstract 1:
Aims /hypothesisObservational and mechanistic studies have suggested a possible relationship between treatment with metformin and decreased incidence of cancer in participants with type 2 diabetes . We extracted data for malignancies from the ADOPT ( A Diabetes Outcome Progression Trial ) and RECORD ( Rosiglitazone Evaluated for Cardiovascular Outcomes and Regulation of Glycaemia in Diabetes ) r and omised controlled clinical trials , in which the efficacy and /or safety of metformin was assessed in comparison with sulfonylureas and rosiglitazone . Methods Neoplasm occurrences were collected as adverse events in these studies . We review ed and re-analysed the individual participant data in both studies for serious adverse events , malignancies reported as adverse events and related neoplasms of special interest . Results In ADOPT , 50 participants ( 3.4 % ) on  metformin  and 55 ( 3.8 % ) on each of rosiglitazone and glibenclamide ( known as glyburide in the USA and Canada ) developed serious adverse event malignancies ( excluding non-melanoma skin cancers ) . This corresponds to 1.03 , 1.12 and 1.31 per 100 person-years , giving hazard ratios for metformin of 0.92 ( 95 % CI 0.63–1.35 ) vs rosiglitazone and 0.78 ( 0.53–1.14 ) vs glibenclamide . In RECORD , on a background of sulfonylurea , 69 ( 6.1 % ) participants developed malignant neoplasms in the metformin group , compared with 56 ( 5.1 % ) in the rosiglitazone group ( HR 1.22 [ 0.86–1.74 ] ) . On a background of metformin , 74 ( 6.7 % ) participants in the sulfonylurea group developed malignant neoplasms , compared with 57 ( 5.1 % ) in the rosiglitazone group ( HR 1.33 [ 0.94–1.88 ] ) . Conclusions /interpretationThe malignancy rates in these two r and omised controlled clinical trials do not support a view that metformin offers any particular protection against malignancy compared with rosiglitazone . However , they do not refute the possibility of a difference compared with sulfonylureas


Title 2:
Type 2 diabetes mellitus and medications for type 2 diabetes mellitus are associated with risk for and mortality from cancer in a German primary care cohort.
Abstract 2:
There is growing evidence that patients with type 2 diabetes mellitus have increased  cancer risk . We examined the association between diabetes , cancer , and cancer-related mortality  and hypothesized that insulin sensitizers lower cancer-related mortality . Participants in the Diabetes Cardiovascular Risk and Evaluation : Targets and Essential Data for Commitment of Treatment study , a nationwide cross-sectional and prospect i ve epidemiological study , were recruited from German primary care practice s. In the cross-sectional study , subjects with type 2 diabetes mellitus had a higher prevalence of malignancies ( 66/1308 , 5.1 % ) compared to nondiabetic subjects ( 185/6211 , 3.0 % ) ( odds ratio , 1.64 ; 95 % confidence interval , 1.12 - 2.41 ) before and after adjustment for age , sex , hemoglobin A(1c ) , smoking status , and body mass index . Patients on  metformin had a lower prevalence of malignancies , comparable with that among nondiabetic patients , whereas those on any other oral combination treatment had a 2-fold higher risk for malignancies even after adjusting for possible confounders ; inclusion of metformin in these regimens decreased the prevalence of malignancies . In the prospect i ve analyses , diabetic patients in general and diabetic patients treated with insulin ( either as monotherapy or in combination with other treatments ) had a 2- and 4-fold , respectively , higher mortality rate than nondiabetic patients , even after adjustment for potential confounders ( incidence of cancer deaths in patients with type 2 diabetes mellitus [ 2.6 % ] vs the incidence of cancer deaths in patients without type 2 diabetes mellitus [ 1.2 % ] ) . Our results suggest that diabetes and medications for diabetes , with the exception of the insulin sensitizer metformin , increase cancer risk and mortality
Conclusions Our findings demonstrate that use of metformin was significantly associated with a lower incidence and a better prognosis of ovarian cancer in patients with diabetes .