Risk of haematological malignancies higher in pernicious anaemia patients
Patients with pernicious anaemia (PA) have a higher risk of biliary tract cancers and haematological malignancies, but a lower risk of cancers other than gastric cancer (GC), according to a new meta-analysis.
The databases of PubMed and Embase were accessed and searched for studies reporting incidence rates of non-GCs in patients with PA. Only those that were performed on adults and had complete follow-up data were eligible for inclusion.
A total of 20 papers were included in the meta-analysis, of which only a quarter (n=5; 25 percent) were of high quality. Four studies were of very low quality, five were of low quality and six were of medium quality, as assessed by the Newcastle-Ottawa scale.
Over a cumulative follow-up of 185.5 years, the overall cumulative incidence of cancer was 2.4 percent. Analysis of studies about gastrointestinal cancers other than GC revealed that over 138.8 years of cumulative follow, the incidence rate was 8.2 cases per 100,000 person-years.
In terms of cancers other than gastrointestinal cancers, a 2.6-percent cumulative incidence rate was obtained, yielding an incidence rate of 17.5 cases per 100,000 person-years. The cumulative follow-up period was 150.2 years.
Compared to the general population, PA patients had greater risks of biliary tract cancer (relative risk [RR], 1.81; 95 percent CI, 1.21–2.70) and haematological malignancies such as multiple myeloma (RR, 2.83; 1.76–4.55) and leukaemia (RR, 1.56; 1.16–2.12).
In contrast, the risks of several cancers were significantly lower in PA patients relative to the general population: lung (RR, 0.26; 0.21–0.31), oesophagus (RR, 0.26; 0.18–0.37), colorectal (RR, 0.14; 0.01–0.19), thyroid (RR, 0.34; 0.21–0.57), liver (RR, 0.18; 0.13–0.24) and breast (RR, 0.17; 0.13–0.22) cancer, among others.