Incidence of Second Malignancies for Prostate Cancer

Abstract

IntroductionThere is a need to assess risk of second primary cancers in prostate cancer (PCa) patients, especially since PCa treatment may be associated with increased risk of second primary tumours.MethodsWe calculated standardized incidence ratios (SIRs) for second primary tumours comparing men diagnosed with PCa between 1980 and 2010 in the Canton of Zurich, Switzerland (n = 20,559), and the general male population in the Canton.ResultsA total of 1,718 men developed a second primary tumour after PCa diagnosis, with lung and colon cancer being the most common (15 and 13% respectively). The SIR for overall second primary cancer was 1.11 (95%CI: 1.06–1.17). Site-specific SIRs varied from 1.19 (1.05–1.34) to 2.89 (2.62–4.77) for lung and thyroid cancer, respectively. When stratified by treatment, the highest SIR was observed for thyroid cancer (3.57 (1.30–7.76)) when undergoing surgery, whereas liver cancer was common when treated with radiotherapy (3.21 (1.54–5.90)) and kidney bladder was most prevalent for those on hormonal treatment (3.15 (1.93–4.87)). Stratification by time since PCa diagnosis showed a lower risk of cancer for men with PCa compared to the general population for the first four years, but then a steep increase in risk was observed.ConclusionIn the Canton of Zurich, there was an increased risk of second primary cancers among men with PCa compared to the general population. Increased diagnostic activity after PCa diagnosis may partly explain increased risks within the first years of diagnosis, but time-stratified analyses indicated that increased risks remained and even increased over time.

Is there a role for IGF‐1 in the development of second primary cancers?

“…They found an increased risk of SPCs among men with prostate cancer, compared to the general population (SIR: 1.11, 95% CI: 1.06–1.17). The inconsistency between these two studies may be due to the diagnosis of prostate cancer at an advanced stage with shorter survival in the earlier years of study . Therefore, the chance of developing a SPC was lower than what it is currently, when prostate cancer is generally diagnosed at a less advanced stage.…”

Risk of second primary malignancies among patients with prostate cancer: A population-based cohort study

“…This precluded us from performing any analysis involving these variables. Third, the overall duration of the present study was 11 years, shorter than those of previous studies [8, 11]. Longer follow-up periods are necessary to examine the real effect of RT-induced malignancies.…”

“…There is a trend for a higher risk of developing SPMs in the urinary bladder (adjusted SHR = 1.34, 99.72% CI = 1.07–1.69, p = 0.015) and rectum/anus (adjusted SHR = 1.16, 99.72% CI = 0.99–1.37, p = 0.114). The SEER Program [8] and other large population-based studies [10, 11, 12, 14] reported that men with PCa had a 5%–109% increase in the relative risk of urinary bladder cancer compared to the general population. Elevated risk of SPMs in the kidney was also noted by some authors [8, 9, 11, 12]; in contrast, this finding was absent in this study and some other studies as well [10, 14].…”

“…The SEER Program [8] and other large population-based studies [10, 11, 12, 14] reported that men with PCa had a 5%–109% increase in the relative risk of urinary bladder cancer compared to the general population. Elevated risk of SPMs in the kidney was also noted by some authors [8, 9, 11, 12]; in contrast, this finding was absent in this study and some other studies as well [10, 14]. The significant increase in urinary system cancer may be due to a shared etiology, such as a common carcinogenic pathway related to urinary stasis, chronic inflammatory substances, or genetic mutations [24], particularly for the urinary bladder, which is adjacent to the prostate.…”

“…However, studies from Italy [10] and France [9] including 4,528 and 3,746 men, respectively, did not observe this reduced trend in SPMs after PCa. Moreover, reports from Switzerland [11] and Germany [12] including 20,559 and 59,259 men, respectively, showed that men with PCa had an overall increased risk of 11–14% of SPMs.…”