Analysis of association between new-onset type 2 diabetes mellitus and pancreatic cancer: retrospective research
Authors: Ponomarev P. А. , Moiseenko V. E. , Pavlovsky А. V. , Avanesyan G. R. , Manikhas A. G. , Granov D. А. 
Published: January 2024

Introduction. Pancreatic cancer is characterized by an extremely unsatisfactory prognosis, despite the development of technologies for the treatment of this pathology. In more than 80 % of patients at the time of the initial request for medical care, the disease is represented by a locally advanced or metastatic stage. Currently used methods of treatment of this nosology are most effective at the early stages of the disease. The absence of characteristic clinical, instrumental and laboratory symptoms, as well as organizational measures for the early detection of this neoplasia creates certain difficulties for effective treatment. Type 2 diabetes is probably one of the risk factors for the development of pancreatic cancer. Epidemiological studies have shown that newly diagnosed type 2 diabetes is associated with a 1.5–2.0-fold increased risk of developing pancreatic cancer in patients over 50 years of age. Insulin resistance and its associated hyperglycemia, hyperinsulinemia, and inflammation are thought to be the main mechanisms contributing to the development of diabetes-related pancreatic cancer. New-onset type 2 diabetes mellitus may be a preclinical sign of pancreatic cancer, and patients with newly diagnosed diabetes may constitute a population in which pancreatic cancer can be detected at an early stage, that will significantly improve the results of treatment.

Objective. To analyze the relationship between new-onset type 2 diabetes mellitus and the development of pancreatic cancer.

Material and methods. A retrospective analysis of the medical records of patients with a confirmed diagnosis of pancreatic cancer, who were treated at the Academician A.M. Granov Russian Scientific Center of Radiology and Surgical Technologies from 2019 to 2022, was carried out. As a source of information, data from medical records of inpatient and outpatient treatment cards were used. In total, the data of 203 persons were studied: morphologically confirmed pancreatic ductal adenocarcinoma was diagnosed in 172 patients (group I), in 31 patients pancreatic tumors had a different histological structure: acinar carcinoma, neuroendocrine tumors (group II). Group I excluded 8 patients without diabetes mellitus who were taking medications, which affect the blood glucose levels. The frequency of occurrence of type 2 diabetes mellitus in the groups was analyzed and then the statistical significance was assessed using the calculation of Fisher's exact test. Group I was analyzed by sex and age, then patients from group I aged 50–75 years were divided into 3 subgroups depending on the glycemic profile: 1) patients with long-term type 2 diabetes mellitus (anamnesis more than 3 years); 2) patients with new-onset type 2 diabetes mellitus (anamnesis less than 3 years); 3) patients without disorders of glucose metabolism. In the subgroup of patients with a long history of type 2 diabetes mellitus, the fact of disease decompensation was additionally assessed.

Results. Type 2 diabetes mellitus was more common in patients with pancreatic ductal adenocarcinoma (p 0.01, Fisher's exact test p = 0.0012) than in other pancreatic neoplasms. The age of patients in group I ranged from 36 to 81 years. The average age of men was 61 ± 8.5 years. The average age of women was 58.9 ± 8.2 years. Among patients of group I aged 50–75 years, new-onset type 2 diabetes mellitus occurred in 78 (68.4 %) persons, type 2 diabetes mellitus with an anamnesis of more than 3 years was detected in 19 (16.6 %) patients, normal metabolism of glucose was observed in 17 (14 %) patients. Of 19 patients with a long anamnesis of type 2 diabetes mellitus (more than 3 years), decompensation in the form of impaired glycemic control was observed in 12 (63.2 %) patients before the diagnosis of pancreatic cancer, in 7 (36.8 %) patients no signs of decompensation of the course of type 2 diabetes mellitus were registered.

Conclusions. New-onset type 2 diabetes mellitus occurred in 78 (64.4 %) patients over 50 years of age with pancreatic ductal adenocarcinoma. The data obtained indicate the feasibility of conducting studies to identify patients aged 50–70 years with newly diagnosed type 2 diabetes in the risk group for the development of pancreatic cancer and examine this contingent at the stage of primary health care. Further retrospective as well as prospective multicenter studies on the association between newly diagnosed type 2 diabetes mellitus and the risk of developing pancreatic cancer are required.