title: The Rising Incidence of Younger Patients With Colorectal Cancer: Questions About Screening, Biology, and Treatment.
abstract: Colorectal cancer (CRC) is the third leading cancer diagnosed globally and an important cause of cancer-related mortality. Of interest, while we have witnessed a declining incidence trend over the past few decades in the older population, incidence rates for adolescents and young adults have been increasing steadily. Several factors may well explain this apparent epidemic in the young, namely a lack of routine screening and emerging lifestyle issues such as obesity, lack of exercise, and dietary factors. It is known that both environmental and genetic factors can increase the likelihood of developing CRC. Although inherited susceptibility is associated with the most striking increases in risk, and must always be considered in a young patient with CRC, the majority of CRCs are in fact sporadic rather than familial. Early-onset CRC is a truly heterogeneous disease, with mounting evidence to suggest that this patient population has a distinctive molecular profile, very different to late-onset CRC cases. Currently, both younger and older patients with CRC are treated in essentially the same manner, but with a better understanding of the molecular mechanisms underlying CRC in the young, we will have the opportunity to specifically tailor screening and clinical management strategies in this unique patient population in an effort to improve outcomes. The aim of this review is to outline our current knowledge of the distinguishing features of early-onset CRC, the ongoing research efforts, and the evolving evidence in this field.
authors.affiliation: Centro de Oncologia, Hospital Sírio-Libanês, Rua Dona Adma Jafet, 91-Bela Vista, São Paulo, SP, 01308-050, Brazil.
authors.forename: Louise C
authors.initials: LC
authors.lastname: Connell
authors.affiliation: Centro de Oncologia, Hospital Sírio-Libanês, Rua Dona Adma Jafet, 91-Bela Vista, São Paulo, SP, 01308-050, Brazil.
authors.forename: José Mauricio
authors.initials: JM
authors.lastname: Mota
authors.affiliation: Centro de Oncologia, Hospital Sírio-Libanês, Rua Dona Adma Jafet, 91-Bela Vista, São Paulo, SP, 01308-050, Brazil. ignezbraghiroli@gmail.com.|Department of Radiology and Medical Oncology, Instituto do Câncer do Estado de São Paulo, Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo 251, Quinto andar - Oncologia Clinica, Sao Paulo, SP, 01246-000, Brazil. ignezbraghiroli@gmail.com.
authors.forename: Maria Ignez
authors.initials: MI
authors.lastname: Braghiroli
authors.affiliation: Centro de Oncologia, Hospital Sírio-Libanês, Rua Dona Adma Jafet, 91-Bela Vista, São Paulo, SP, 01308-050, Brazil.|Department of Radiology and Medical Oncology, Instituto do Câncer do Estado de São Paulo, Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Arnaldo 251, Quinto andar - Oncologia Clinica, Sao Paulo, SP, 01246-000, Brazil.
authors.forename: Paulo M
authors.initials: PM
authors.lastname: Hoff
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000628:therapy; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000453:epidemiology / Q000235:genetics; D019468:Disease Management; D055088:Early Detection of Cancer / Q000379:methods; D020022:Genetic Predisposition to Disease; D006801:Humans; D015994:Incidence; D011159:Population Surveillance; D012307:Risk Factors; D055815:Young Adult
keywords: Chromosomal instability; CpG island methylator phenotype; Early-onset colorectal cancer; Epidemiology; Hereditary syndromes; Lynch syndrome; Microsatellite instability; Nonhereditary risk factors; Screening; Sporadic early-onset colorectal cancer