Subject(s)
Brain Neoplasms/diagnosis , Adolescent , Brain Neoplasms/therapy , Child , Early Diagnosis , Humans , Risk Factors , Young AdultABSTRACT
BACKGROUND: Teenagers and young adults (TYA, 15-24 years) diagnosed with cancer report repeated visits to primary care before referral. We investigated associations of symptoms and consultation frequency in primary care with TYA cancers. METHODS: Population-based, case-control study was carried out using data from the Clinical Practice Research Datalink (CPRD). A total of 1064 TYA diagnosed with cancer were matched to 13,206 controls. Symptoms independently associated with specific cancers were identified. Likelihood ratios (LRs) and positive predictive values (PPVs) were calculated. RESULTS: In the 3 months before diagnosis, 397 (42.9%) cases consulted > or =4 times vs 593(11.5%) controls (odds ratio (OR): 12.1; 95% CI: 9.7, 15.1), yielding a PPV for any cancer of 0.018%. The LR of lymphoma with a head/neck mass was 434 (95% CI: 60, 3158), with a PPV of 0.5%. Corresponding figures in other cancers included - LR of leukaemia with lymphadenopathy (any site): 29 (95% CI: 8, 112), PPV 0.015%; LR of CNS tumour with seizure: 56 (95% CI: 19, 163), PPV 0.024%; and LR of sarcoma with lump/mass/swelling: 79 (95% CI: 24, 264), PPV 0.042%. CONCLUSION: Teenagers and young adults with cancer consulted more frequently than controls in the 3 months before diagnosis. Primary care features of cancer match secondary care reports, but were of very low risk; nonetheless, some features increased the likelihood of cancer substantially and should be taken seriously when assessing TYA.
Subject(s)
Neoplasms/diagnosis , Neoplasms/epidemiology , Primary Health Care/statistics & numerical data , Adolescent , Adult , Case-Control Studies , Humans , Referral and Consultation/statistics & numerical data , Risk , United Kingdom/epidemiology , Young AdultABSTRACT
BACKGROUND: This study investigated the risk of cancer in children with alert symptoms identified in current UK guidance, or with increased consultation frequency in primary care. METHODS: A population-based, nested case-control study used data from the General Practice Research Database. In all, 1267 children age 0-14 years diagnosed with childhood cancer were matched to 15,318 controls. Likelihood ratios and positive predictive values (PPVs) were calculated to assess risk. RESULTS: Alert symptoms recorded in the 12 and 3 months before diagnosis were present in 33.7% and 27.0% of cases vs 5.4% and 1.4% of controls, respectively. The PPV of having cancer for any alert symptom in the 3 months before diagnosis was 0.55 per 1000 children. Cases consulted more frequently particularly in the 3 months before diagnosis (86% cases vs 41% controls). Of these, 36% of cases and 9% of controls had consulted 4 times or more. The PPV for cancer in a child consulting 4 times or more in 3 months was 0.13 per 1000 children. CONCLUSION: Alert symptoms and frequent consultations are associated with childhood cancer. However, individual symptoms and consultation patterns have very low PPVs for cancer in primary care (e.g., of 10,000 children with a recorded alert symptom, approximately 6 would be diagnosed with cancer within 3 months).
Subject(s)
Neoplasms/diagnosis , Neoplasms/epidemiology , Adolescent , Age Factors , Case-Control Studies , Child , Child, Preschool , Family Practice , Female , Humans , Infant , Male , Population Surveillance , Primary Health Care , Risk , United Kingdom/epidemiologyABSTRACT
The human collectin, mannose-binding lectin (MBL), is an important protein of the humoral innate immune system. With multiple carbohydrate-recognition domains, it is able to bind to sugar groups displayed on the surfaces of a wide range of microorganisms and thereby provide first-line defence. Importantly, it also activates the complement system through a distinctive third pathway, independent of both antibody and the C1 complex. Three single point mutations in exon 1 of the expressed human MBL-2 gene appear to impair the generation of functional oligomers. Such deficiencies of functional protein are common in certain populations, e.g. in sub-Saharan Africa, but virtually absent in others, e.g. indigenous Australians. MBL disease association studies have been a fruitful area of research and implicate a role for MBL in infective, inflammatory and autoimmune disease processes. Overall, there appears to be a genetic balance in which individuals generally benefit from high levels of the protein. However, in certain situations, reduced levels of circulating MBL may be beneficial to the host and this may explain the persistence of the deleterious gene polymorphisms in many population groups.
