Time trends in incidence and survival of small intestinal cancer in Sweden

Abstract

Background Small intestinal cancer is less common than some other gastrointestinal malignancies. Tumours of different histological types and anatomical sites of origin have therefore often been described together. The aim of this study was to investigate the epidemiology for each of the four main subtypes: duodenal adenocarcinoma (D-AC), duodenal neuroendocrine tumour (D-NET), jejunoileal adenocarcinoma (J/I-AC), and jejunoileal neuroendocrine tumour (J/I-NET). Methods All patients with small intestinal cancer diagnosed between 1960 and 2015 were identified from the Swedish Cancer Register. The age-adjusted incidence rate with incidence rate ratios, as well as overall (OS) and net (NS) survival, were determined and temporal trends were analysed. Results The incidence rate was highest for J/I-NET, with 9.98 clinical diagnoses per million in 2010–2015. Clinical diagnosis of D-AC increased more than 10-fold and surpassed J/I-AC as the second most common subtype. D-NET was by far the least common subtype. Diagnosis at autopsy became less common over time, whereas clinical diagnoses increased significantly for all four subtypes. All subtypes except J/I-AC affected men more often than women. The age distribution was similar between subtypes, although patients with adenocarcinomas were slightly older. Survival was generally much better for patients with NET than for those with adenocarcinoma. Both OS and NS showed a negative association with advancing age. Survival improved only for J/I-NET from a 5-year NS of 0.69 in the 1960s to 0.81 in 2010–2015. Conclusion The incidence of small intestinal cancer is increasing, particularly for D-AC and in the elderly. Survival of patients with small intestinal cancer has improved only for J/I-NET over the last decades.

Survival in Colon, Rectal and Small Intestinal Cancers in the Nordic Countries through a Half Century

“…Colon cancer is in men about 1.5 times and in women 2 times more common than rectal cancer and over 10 times more common than small intestinal cancer (SIC) in Northern Europe [1]. These cancers are largely adenocarcinomas, except that in SIC adenocarcinomas and indolent neuroendocrine tumors (NET, carcinoids) they are present with approximately equal proportions [2][3][4][5][6]. SIC also includes rare sarcomas and gastrointestinal stromal tumors.…”

“…The earlier increase in the incidence of colon and rectal cancers has slowed down and mortality has started to decline in all Nordic countries; the contribution of the organized screening to mortality decline is unclear, as it was implemented only in Finland (FI, guaiacbased fecal occult blood test in 2004-2016 followed by fecal immunohistochemical testing, FIT) and in Denmark (DK, FIT since 2014), and not in Norway (NO) or Sweden (SE) [7]. The incidence of SIC has continuously increased in DK and SE, particularly for adenocarcinoma; improving imaging techniques have most likely contributed to the detection of NETs [5,6]. Colon and rectal cancers are often considered jointly as colorectal cancer (CRC) as they share many aspects of biology and pathology, including risk factors which include many dietary factors, physical inactivity, obesity, type 2 diabetes, smoking, alcohol and inflammatory bowel disease [8][9][10].…”

“…While diagnostic endoscopy has become commonplace for colon and rectal cancers, it has not yet become commonplace for SIC. NET is an indolent tumor which may be surgically removed [2,5,24]. NET may present as multiple synchronous or asynchronous primaries, but it rarely metastasizes with the primary target being the liver [18,25,26].…”

“…NET may present as multiple synchronous or asynchronous primaries, but it rarely metastasizes with the primary target being the liver [18,25,26]. Global survival in these cancers has developed favorably [5,22,27,28].…”

Comparison of Endoscopic Ultrasonography and Conventional Endoscopy for Prediction of Tumor Depth in Superficial Nonampullary Duodenal Epithelial Tumors

“…The incidence of duodenal carcinoma (DC) was reported as 2.9-4.3 per 1,000,000 person-years in the USA and in European countries [1][2][3][4][5][6]. Along with the widespread permeation of endoscopic screening programs, the incidence of superficial nonampullary duodenal epithelial tumors (SNADETs) in Japan has increased [1,7].…”