Chronic Inflammation Predisposing to Cancer Metastasis: Lesson Learned from a Chronically Embedded Foreign Body in a Duodenal Diverticulum

Abstract

Malignant neoplasms of small intestine are uncommon and account for less than 0.3 % of all gastrointestinal tract malignancies [1]. Despite the fact that the small intestine accounts for 75 % of the gastrointestinal tract, metastasis to the small bowel is also rare and has been reported in only 2 % of autopsies [2, 3]. Most of the metastases to small intestine originate from melanoma, renal cell carcinoma, genitourinary neoplasms, carcinoma of cervix, thyroid carcinoma, merkel cell carcinoma, breast cancer, Kaposi’s sarcoma, and lung cancer [3–8]. Accidental foreign body (FB) ingestion is common. Although most cases occur in pediatric populations, FB ingestion in adults is not uncommon [9]. Fortunately, approximately 90 % of the time, objects pass through the system without any complications [10]. However, if retained within the digestive tract and FB may become impacted and can cause perforation, obstruction, and bleeding. Additionally, an embedded FB may trigger inflammation, which over time may lead to consequent malignant transformation of the local tissue [11–13]. The theory of FB-induced carcinogenesis has been a focus of extensive research for decades. Turner reported that subcutaneous implantation of FB disks in rats led to formation of sarcoma surrounding the immediate vicinity of the disks [14]. Since then, numerous studies have linked FB-induced inflammation to carcinogenesis [12]. However, metastasis from other sites to an area with an embedded FB has seldom been reported. Here, we report a case of a 75-year-old female with a history of colon cancer, resected 5 years previously, whom was found to have metastatic colon cancer to a duodenal diverticulum with an impacted foreign body which had been there for at least 5 years prior to presentation.