ABSTRACT
Immune checkpoint inhibitors (ICIs) have emerged as a novel class of anti-neoplastic agent in oncology. Their integration into practice has been accompanied by "immune-related adverse events" (irAEs) wherein off-target immune responses damage healthy tissues. Severe irAEs can cause irreversible organ dysfunction and death. Despite this, little is known about factors which predispose certain patients to develop irAEs or which precipitate their onset. Here, we report a case of a patient with melanoma who completed adjuvant immunotherapy, underwent elective hip replacement, and developed a rare rheumatologic irAE (remitting seronegative symmetrical synovitis with pitting edema) post-operatively. Mechanistically, we hypothesize that surgery contributed to irAE pathogenesis as a sensitizing event in which self-antigens were presented to an immune system with diminished peripheral tolerance in the context of recent ICI administration. This case highlights a need for future correlative analyses, investigating whether iatrogenic interventions such as surgery might be associated with irAE development.
ABSTRACT
BACKGROUND: Screening sigmoidoscopy is effective in reducing mortality from colorectal cancer. In 2009, Cancer Care Ontario (CCO) launched a nurse-performed screening flexible sigmoidoscopy program at Hotel Dieu Hospital, Kingston, Ontario. Prior to this program, there was a pilot sigmoidoscopy screening program by gastroenterologists in a similar average risk cohort. AIM: To compare neoplasia detection rates and associated costs of screening sigmoidoscopy performed by nurses and gastroenterologists. METHOD: A retrospective chart review was conducted on flexible sigmoidoscopies performed as part of two average risk screening programs performed by gastroenterologists and nurse-endoscopists. Detected polyps were categorized as hyperplastic, low-risk adenomas or high-risk adenomas. Average cost per procedure was estimated based on physician fee for service charges, nurse wage and benefits, physician supervisory fees, pathology costs and administrative expenses. RESULTS: There were 538 procedures performed by nurses and 174 by physicians. Adenomas were detected in 18% of nurse-performed procedures versus 9% in physician-performed procedures (p=0.003), with the higher adenoma detection rate restricted to low risk adenomas. One cancer was found in the physician group. Seven physicians performed the 174 sigmoidoscopies, with one physician performing the majority. This physician's adenoma detection rate was 4.5%, whereas detection rate for the remaining physicians combined was 16.5%. Nurses biopsied more polyps per case (0.96 versus 0.18). Average estimated cost per case was greater for nurses ($387.54 versus $309.37). CONCLUSION: Well-trained nurse-endoscopists can provide an effective service for colorectal cancer screening, but as currently structured in Ontario, the associated cost is higher for nurse-performed procedures.
