Cancer and comorbidity: The role of leptin in breast cancer and associated pathologies

Table 1 Selected recent reports on diabetes and epidemiological/clinical characteristics of breast cancer

Authors and report time	Study types, geographical areas and patients	Findings in brief
Bronsveld et al[44] 2017	Population-based cohort study among British population, 2371 breast cancer cases during approximately 1.6 million person-years	Approximately 2880 women with T2D are diagnosed with breast cancer per year in the United Kingdom
Charlot et al[45] 2017	1621 African-American women with invasive breast cancer (232 had T2D) were followed	A positive association of T2D with breast cancer mortality
Dankner et al[46] 2016	Israel, 2186196 individuals (prevalent diabetes: 159104 and incident diabetes: 408243) were followed for various cancers	Diabetes posed an increased risk of breast cancer in postmenopausal women
Gini et al[47] 2016	Retrospective population-based cohort study, Italy, 32247 T2D patients	T2D patients are at increased risk of several cancers, and of premature death in women with breast cancer
Lipscombe et al[48] 2015	Retrospective cohort study, Ontario, Canada, 38407 women with breast cancer (6115 had diabetes)	Diabetes was associated with more advanced-stage breast cancer
Luo et al[49] 2014	Women’s Health Initiative, United States, 8108 women with breast cancer	T2D increased risk of total mortality among women with breast cancer
Ma et al[50] 2014	China, 865 early stage triple-negative breast cancer cases	T2D exhibited a significantly lower disease-free survival; increased likelihood of recurrence and metastasis
Maskarinec et al[51] 2017	Multiethnic cohort, Among 103721 women with 14558 T2D cases, 6692 women developed breast cancer	T2D status was primarily associated with higher breast cancer risk in Latinas
Palmer et al[52] 2017	Prospective cohort of African-American women, 1851 breast cancer cases during 847934 person-years of follow-up	Women with T2D were at increased risk of developing ER(-) breast cancer
Pan et al[53] 2018	Prospective study in China, 17463 incident cases (various cancers) among 508892 participants	Participants with T2D had increased risks of breast cancer
Samson et al[54] 2016	Retrospective cohort study, South Carolina, 7310 participants (3835 European-origin and 3475 African-American women)	Negative association between T2D and breast cancer was stronger in African-American women
Wu et al[55] 2015	Multiethnic cohort, California, 8952 breast cancer cases	Risk of mortality increased among cases with diabetes
Xu et al[56] 2015	Population-based retrospective cohort study, China, 36379 T2D patients	Elevated risk of breast cancer

T2D: Type-2 diabetes; ER(-): Estrogen receptor negative; Person-years: Amount of total time in years contributed by all participants.