Prostate cancer survivors: Risk and mortality in second primary cancers

Causal relationship between prostate cancer and 12 types of cancers: multivariable and bidirectional Mendelian randomization analyses

BACKGROUND

Previous observational studies have shown an association between certain cancers and the subsequent risk of prostate cancer (PCa). However, the causal relationship between these cancers and PCa is still unclear. This study aimed to investigate the causal relationship between 12 common cancers and the risk of PCa.

METHODS

We employed genome-wide association studies (GWAS) to perform forward and reverse Mendelian randomization (MR) within two-sample frameworks. Furthermore, we conducted multivariable MR analyses to investigate the relationships between different types of cancer. In addition, multiple sensitivity analysis methods were employed to assess the robustness of our findings.

RESULTS

Our univariable MR analysis showed that genetically predicted hematological cancer was associated with a reduced risk of PCa (OR: 0.911, 95% CI 0.89-0.922, P = 0.03). Furthermore, MR analysis demonstrates that genetically predicted occurrence of thyroid gland and endocrine gland cancer also raised the risk of PCa (all P < 0.05). Multivariable analysis showed that thyroid gland cancer exhibited a higher incidence of PCa (OR: 1.12, 95% CI: 1.08-1.16, P = 0.008). In the reverse MR analysis, we found no significant inverse causal associations between PCa and 12 types of cancers.

CONCLUSION

In summary, this study provided insights into the causal relationships between various types of cancer and PCa. Hematological cancer was suggested to associate with a lower risk of PCa, while thyroid gland cancer and endocrine gland cancer might increase the risk. These findings contribute to the understanding of genetic factors related to PCa and its potential associations with other cancers.

PSMA PET/CT in Castration-Resistant Prostate Cancer: Myth or Reality?

BACKGROUND

prostate-specific membrane antigen (PSMA) ligand PET has been recently incorporated into international guidelines for several different indications in prostate cancer (PCa) patients. However, there are still some open questions regarding the role of PSMA ligand PET in castration-resistant prostate cancer (CRPC). The aim of this work is to assess the clinical value of PSMA ligand PET/CT in patients with CRPC.

RESULTS

PSMA ligand PET has demonstrated higher detection rates in comparison to conventional imaging and allows for a significant reduction in the number of M0 CRPC patients. However, its real impact on patients' prognosis is still an open question. Moreover, in CRPC patients, PSMA ligand PET presents some sensitivity and specificity limitations. Due to its heterogeneity, CRPC may present a mosaic of neoplastic clones, some of which could be PSMA-/FDG+, or vice versa. Likewise, unspecific bone uptake (UBU) and second primary neoplasms (SNPs) overexpressing PSMA in the neoangiogenic vessels represent potential specificity issues. Integrated multi-tracer imaging (PSMA ligand and [18F]FDG PET) together with a multidisciplinary discussion could allow for reaching the most accurate evaluation of each patient from a precision medicine point of view.

Clinical characteristics and prostate-cancer-specific mortality of competitive risk nomogram in the second primary prostate cancer

Background

With the development of early diagnosis and treatment, the second primary malignancy (SPM) attracts increasing attention. The second primary prostate cancer (spPCa) is an important class of SPM, but remains poorly understood.

Methods

We retrospectively analyzed 3,322 patients with spPCa diagnosed between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. Chi-square test was applied to compare demographic and clinical variables and analyze causes of death. Multivariate competitive risk regression model was used to identify risk factors associated with prostate-cancer-specific mortality (PCSM), and these factors were enrolled to build a nomogram of competitive risk. The C-index, calibration curve, and decision curve analysis (DCA) were employed to evaluate the discrimination ability of our nomogram.

Results

The median follow-up (interquartile range, IQR) time was 47 (24-75) months, and the median (IQR) diagnosis interval between the first primary cancer (FPC) and spPCa was 32 (16-57) months. We found that the three most common sites of SPM were the urinary system, digestive system, and skin. Through multivariate competitive risk analysis, we enrolled race (p < 0.05), tumor-node-metastasis (TNM) stage (p < 0.001), Gleason score (p < 0.05), surgery (p = 0.002), and radiotherapy (p = 0.032) to construct the model to predict the outcomes of spPCa. The C-index was 0.856 (95% CI, 0.813-0.899) and 0.905 (95% CI, 0.941-0.868) in the training and validation set, respectively. Moreover, both the calibration curve and DCA illustrated that our nomogram performed well in predicting PCSM.

Conclusion

In conclusion, we identified four risk factors associated with the prognosis of spPCa and construct a competing risk nomogram, which performed well in predicting the 3-, 5-, and 10-year PCSM.

Risk prediction of second primary malignancies in primary colorectal neuroendocrine neoplasms patients: a population-based study

PURPOSE

In this study, we aimed to identify risk factors for developing second primary malignancies (SPMs) in colorectal neuroendocrine neoplasms (NENs) patients and develop a competing-risk nomogram to predict SPMs' probabilities quantitatively.

METHODS

Patients with colorectal NENs were retrospectively collected from the Surveillance, Epidemiology, and End Results (SEER) database during 2000-2013. Potential risk factors for SPMs' occurrence in colorectal NENs' patients were identified by the Fine and Gray's proportional sub-distribution hazards model. Then, a competing-risk nomogram was constructed to quantify SPMs' probabilities. The discriminative abilities and calibrations of this competing-risk nomogram were assessed by the area under the receiver-operating characteristic (ROC) curves (AUC) and calibration curves.

RESULTS

We identified 11,017 colorectal NENs' patients, and randomly divided them into training (n = 7711 patients) and validation (n = 3306 patients) cohorts. In the whole cohort, 12.4% patients (n = 1369) had developed SPMs during the maximum follow-up of approximately 19 years (median 8.9 years). Sex, age, race, primary tumor location, and chemotherapy were identified as risk factors for SPMs' occurrence in colorectal NENs' patients. Such factors were selected to develop a competing-risk nomogram and showed excellent predictive ability for SPMs' occurrence (the 3-, 5-, and 10-year AUC values were 0.631, 0.632, and 0.629 in the training cohort and 0.665, 0.639, 0.624 in the validation cohort, respectively).

CONCLUSIONS

This research identified risk factors for SPMs' occurrence in colorectal NENs' patients. Competing-risk nomogram was constructed and proved to have good performance.

Development and Validation of a Nomogram for Predicting Overall Survival in Patients with Second Primary Small Cell Lung Cancer After Non-Small Cell Lung Cancer: A SEER-Based Study

Background

Non-small cell lung cancer (NSCLC) survivors are at an increased risk of developing second primary malignancies, such as small cell lung cancer. This paper sought to establish a prognostic nomogram to assess overall survival (OS) in patients with second primary small cell lung cancer (SPSCLC) after NSCLC.

Methods

420 patients who developed SPSCLC after NSCLC were randomly split into the training and validation groups. A nomogram was established by stepwise regression. Area under the curve (AUC) and calibration plots were applied to assess the prognostic performance of the nomogram. Concordance index (C-index), integrated discrimination improvement (IDI), net reclassification index (NRI) and decision curve analysis (DCA) were performed to compare the nomogram with the American Joint Committee on Cancer (AJCC) 8th staging system. Survival risk classification was constructed based on the nomogram.

Results

Five variables were chosen to construct the nomogram. The AUC showed that it had a satisfactory discrimination ability. All calibration plots displayed good concordance between nomogram and observation. The C-index, IDI, NRI and DCA showed the nomogram was superior to the AJCC 8th staging system. The Kaplan-Meier curves suggested huge differences in prognosis among the three risk groups.

Conclusion

This study build a nomogram and risk stratification system for predicting probabilities of OS in patients with SPSCLC after NSCLC, which can help clinicians in individualized survival assessment and treatment decisions.

Risk of second primary malignancies associated with radiotherapy in prostate cancer patients: competing risk analysis

Background: The effect of radiotherapy (RT) for second primary malignancies (SPMs) among prostate cancer survivors is controversial. Methods: Applying logistic regression, competing risk analysis and propensity score matching method, this study analyzed clinical data from the Surveillance, Epidemiology, and End Results program to compare the risk for SPMs between patients receiving RT and non-RT. Results: In this study, prostate cancer patients treated with RT developed more SPMs in the anus, bladder, rectum, liver, lung and bronchus and lymphoma than non-RT groups. Conclusion: More intensive surveillance should be adopted for these cancers among prostate cancer survivors.

Second primary malignancies in colorectal cancer patients

The prevalence of second primary malignancies (SPMs) in the western world is continually increasing with the risk of a new primary cancer in patients with previously diagnosed carcinoma at about 20%. The aim of this retrospective analysis is to identify SPMs in colorectal cancer patients in a single-institution cohort, describe the most frequent SPMs in colorectal cancer patients, and discover the time period to occurrence of second primary tumors. We identified 1174 patients diagnosed with colorectal cancer in the period 2003–2013, with follow-up till 31.12.2018, and median follow-up of 10.1 years, (median age 63 years, 724 men). A second primary neoplasm was diagnosed in 234 patients (19.9%). Older age patients, those with early-stage disease and those with no relapse have a higher risk of secondary cancer development. The median time from cancer diagnosis to development of CRC was 8.9 years for breast cancer and 3.4 years for prostate cancer. For the most common cancer diagnosis after primary CRC, the median time to development was 0–5.2 years, depending on the type of malignancy. Patients with a diagnosis of breast, prostate, or kidney cancer, or melanoma should be regularly screened for CRC. CRC patients should also be screened for additional CRC as well as cancers of the breast, prostate, kidney, and bladder. The screening of cancer patients for the most frequent malignancies along with systematic patient education in this field should be the standard of surveillance for colorectal cancer patients.

Clinical characteristics and overall survival nomogram of second primary malignancies after prostate cancer, a SEER population-based study

Prostate cancer (PCa) is the most prevalent cancer among males and the survival period of PCa has been significantly extended. However, the probability of suffering from second primary malignancies (SPMs) has also increased. Therefore, we downloaded SPM samples from the SEER database and then retrospectively analyzed the general characteristics of 34,891 PCa patients diagnosed between 2000 and 2016. After excluding cases with unknown clinical information, 2203 patients were used to construct and validate the overall survival (OS) nomogram of SPM patients after PCa. We found that approximately 3.69% of PCa patients were subsequently diagnosed with SPMs. In addition, the three most prevalent sites of SPM were respiratory and intrathoracic organs, skin, and hematopoietic system. The top three histological types of SPMs were squamous cell carcinoma, adenoma and adenocarcinoma, nevi and melanoma. Through univariate and multivariate Cox regression analysis, we found that the site of SPM, age, TNM stage, SPM surgery history, and PCa stage were associated with the OS of SPM. By virtue of these factors, we constructed a nomogram to predict the OS of SPM. The C-index in the training set and validation set were 0.824 (95CI, 0.806-0.842) and 0.862 (95CI, 0.840-0.884), respectively. Furthermore, we plotted the receiver operating characteristic curve (ROC) and the area under curve (AUC) which showed that our model performed well in assessing the 3-year (0.861 and 0.887) and 5-year (0.837 and 0.842) OS of SPMs in the training and validation set. In summary, we investigated the general characteristics of SPMs and constructed a nomogram to predict the prognosis of SPM following PCa.

The Risk of Second Primary Cancers in Prostate Cancer Survivors Treated in the Modern Radiotherapy Era

Purpose

Concerns have been raised that modern intensity modulated radiotherapy (IMRT) may be associated with increased second primary cancer risks (SPC) compared to previous three-dimensional conformal radiation techniques (3DCRT), due to increased low dose volumes and more out-of-field ionizing dose to peripheral tissue further away from the target. We assessed the impact of treatment technique on SPC risks in a cohort of prostate cancer (PCa) survivors.

Material and Methods

The study cohort comprised 1,561 PCa survivors aged 50–79 years at time of radiotherapy, treated between 2006–2013 (N=707 IMRT, N=854 3DCRT). Treatment details were extracted from radiotherapy systems and merged with longitudinal data of the Netherlands Cancer Registry to identify SPCs. Primary endpoint was the development of a solid SPC (excluding skin cancer) in peripheral anatomical regions, i.e. non-pelvic. Applied latency period was 12 months. SPC rates in the IMRT cohort (total cohort and age subgroups) were compared to 1) the 3DCRT cohort by calculating Sub-Hazard Ratios (sHR) using a competing risk model, and 2) to the general male population by calculating Standardized Incidence Ratios (SIR). Models were adjusted for calendar period and age.

Results

Median follow-up was 8.0 years (accumulated 11,664 person-years at-risk) with 159 cases developing ≥1 non-pelvic SPC. For IMRT vs 3DCRT we observed a significantly (p=0.03) increased risk (sHR=1.56, 95% Confidence Interval (CI) 1.03–2.36, corresponding estimated excess absolute risk (EAR) of +7 cases per 10,000 person-years). At explorative analysis, IMRT was in particular associated with increased risks within the subgroup of active smokers (sHR 2.94, p=0.01). Within the age subgroups 50–69 and 70–79 years, the sHR for non-pelvic SPC was 3.27 (p=0.001) and 0.96 (p=0.9), respectively. For pelvic SPC no increase was observed (sHR=0.8, p=0.4). Compared to the general population, IMRT was associated with significantly increased risks for non-pelvic SPC in the 50–69 year age group (SIR=1.90, p<0.05) but not in the 70–79 years group (SIR=1.08).

Conclusion

IMRT is associated with increased SPC risks for subjects who are relatively young at time of treatment. Additional research on aspects of IMRT that may cause this effect is essential to minimize risks for future patients receiving modern radiotherapy.

Conditional Relative Survival and Competing Mortality of Patients with Prostate Cancer in Korea: A Nationwide Cohort Study

BACKGROUND

Conditional relative survival (CRS) and competing mortality are important survivorship issues after cancer treatment. We aimed to investigate them among patients with prostate cancer treated by various modalities.

METHODS

Using a nationwide population-based database, we calculated 5-year CRS conditioned on 1 through 5 years survival after diagnosis. These rates were stratified by age, sex, socioeconomic status, comorbidities, and treatment received. Cause of death and estimated cause-specific mortality were also described and considered with competing risks.

RESULTS

A total of 81,773 patients newly diagnosed with primary prostate cancer from 2007 to 2013 were identified. The 5-year CRS was 81.1% at baseline, but increased gradually up to 95.4% at 4 years and exceeded 100% at 5 years after diagnosis, suggesting no excess mortality compared with the general population. However, this pattern differed by treatment received. Patients who underwent androgen deprivation therapy showed 5-year CRS of only 88.4% at 5 years after diagnosis, implying persistent excess mortality. Prostate cancer constituted around one-third of deaths, while other cancers were the main cause of death within <2 years after diagnosis. Noncancer-related deaths, including cardiovascular disease and respiratory disease, increased with time since diagnosis.

CONCLUSIONS

CRS rates for patients with prostate cancer improved over time and exceeded that of the general population at 5 years. Other cancers were the main cause of death in the earlier survivorship phase, and deaths from noncancer causes gradually increased over time.

IMPACT

Our findings will help patients and clinicians make evidence-based decisions on the basis of a patient's dynamic risk profile.

Rate differences between first and second primary cancers may outline immune dysfunction as a key risk factor

Background

Many cancers are increased in immunosuppressed patients and evidence is accumulating that immune dysfunction may be a contributing risk factor for second primary cancers (SPCs). The aim of this study was to explore the potential influence of immune mechanisms in SPC.

Methods

We used the Swedish Cancer Registry (1990‐2015) to select 13 male and 14 female first primary cancers (FPCs) that are known to be related to immune suppression. We assessed relative risks (RRs) for any of these as concordant (same first and second cancer) and discordant FPC‐SPC pairs. Hierarchical clustering of significant RRs was performed for cancers as FPC and SPC.

Results

Concordant risks for SPCs were excessive in men and women for nasal (RRs 59.3 for men and 150.6 for women), tongue/mouth (51.7 and 100.8), and lip (32.4 and 61.2) cancers. Heatmaps showed that some cancers, such as skin cancer, tongue/mouth cancers, and non‐Hodgkin lymphoma had multiple bidirectional associations as FPC and SPC. Nasal cancer and chronic lymphocytic leukemia had associations mainly as FPC while liver and kidney cancers showed most associations as SPC.

Conclusions

Immune dysfunction may be a plausible contributing factor for most of the associations, which calls for experimental verification.

Racial and ethnic differences in risk of second primary cancers among prostate cancer survivors

PURPOSE

Previous studies have shown an overall decreased risk of second cancers among prostate cancer survivors, but this has not been comprehensively examined by race/ethnicity. We conducted a retrospective cohort study of 716,319 one-year survivors of prostate cancer diagnosed at ages 35-84 during 2000-2015 as reported to 17 US Surveillance, Epidemiology and End Results (SEER) registries.

METHODS

We estimated standardized incidence ratios (SIRs) for second primary non-prostate malignancies by race/ethnicity (non-Latino white, Black, Asian/Pacific Islander [API] and Latino), by Gleason, and by time since prostate cancer diagnosis. Poisson regression models were used to test heterogeneity between groups with the expected number as the offset.

RESULTS

60,707 second primary malignancies were observed. SIRs for all second cancers combined varied significantly by race/ethnicity: SIR_white: 0.88 (95% confidence interval: 0.87-0.89), SIR_Latino: 0.92 (0.89-0.95), SIR_Black: 0.97 (0.95-0.99), and SIR_API: 1.05 (1.01-1.09) (p-heterogeneity < 0.001). SIRs for all cancers combined were higher among survivors of higher vs. lower Gleason prostate cancers irrespective of race/ethnicity. We observed significant heterogeneity by race/ethnicity in SIRs for 9 of 14 second cancer types investigated including lung, bladder, kidney, and liver.

CONCLUSIONS

Our results confirm that most prostate cancer survivors have lower risks of second cancers than expected, but the magnitude varied by race/ethnicity. Exceptionally, API men had small but significantly increased risk. Further research to understand drivers of the observed race/ethnicity heterogeneity is warranted.

Incidence Differences Between First Primary Cancers and Second Primary Cancers Following Skin Squamous Cell Carcinoma as Etiological Clues

Background

Most literature on second primary cancers (SPCs) focuses on possible factors, which may increase the risk of these cancers, and little attention has been paid for the overall incidence differences between first primary cancers (FPCs) and same SPCs. We wanted to compare the incidence rates for all common cancers when these were diagnosed as FPCs and SPCs after invasive and in situ squamous cell carcinoma (SCC) of the skin, which are usually treated by surgery only.

Methods

Cancers were identified from the Swedish Cancer Registry from the years 1990 through to 2015, and they included, in addition to skin cancers, 20 male cancers totaling 484,850 patients and 22 female cancers totaling 452,909 patients. Standardized incidence rates and relative risks (RRs) were calculated for sex-specific common cancers as FPC and as SPC after skin SCC. Spearman rank correlations were used in the analysis of incidence ranking of FPC and SPC.

Results

Of total, 29,061 men and 23,533 women developed invasive SCC and 27,842 men and 36,383 women in situ SCC. The total number of 20 other male cancers was 484,850 and of 22 female cancers it was 452,909. Rank correlations ranged from 0.90 to 0.96 (P~5×10^-6), indicating that overall skin SCC did not interfere with SPC formation. The exceptions were increased SPC risks for melanoma, sharing risk factors with skin SCC, and non-Hodgkin and Hodgkin lymphoma, and cancers of the upper aerodigestive tract, connective tissue, and male and female genitals suggesting contribution by skin cancer initiated immune dysfunction.

Conclusion

The incidence ranking of SPCs after skin cancers largely follows the incidence ranking of FPCs indicating that overall skin SCC does not greatly interfere with the intrinsic carcinogenic process. The main deviations in incidence between FPC and SPC appeared to be due to shared risk factors or immunological processes promoting immune responsive cancer types.

Influence of family history on risk of second primary cancers and survival in patients with squamous cell skin cancer

BACKGROUND

Patients with squamous cell skin cancer (SCC) have an excellent prognosis but second primary cancers (SPCs) weaken survival prospects. Family history is a known risk factor for cancer but whether it is a risk factor for SPC in patients with SCC is not known.

OBJECTIVES

To quantify the risk of family history on SPCs in patients with SCC and estimate survival probabilities of patients with SPCs depending on family history.

METHODS

With 13 945 histologically verified SCCs, relative risks (RRs) were estimated for family history using a generalized regression model. For survival analysis, hazard ratios (HRs) were assessed using a multivariable Cox proportional-hazards model.

RESULTS

Family history of invasive SCC increased risk of second invasive SCC [RR = 42·92, 95% confidence interval (CI) 33·69-50·32] compared with risk without family history (RR 19·12, 95% CI 17·88-21·08). Family history of any nonskin cancer in invasive SCC increased risk of the same cancers to be diagnosed as SPC (RRF_H = 1·48, 95% CI 1·35-1·61 vs. RR_{no FH} = 1·40, 95% CI 1·32-1·48); significant increases were observed for seven different nonskin cancers. Most results were replicated for in situ SCC. SPC was deleterious for survival irrespective of family history; HR for patients with SPC was 4·28 (95% CI 3·83-4·72) vs. those without SPC (1·04).

CONCLUSIONS

Family history of nonskin cancer was associated with approximately a doubling of risk for SPCs in patients with SCC. SPC increases the death rate in patients with SCC 3-4 times, irrespective of family history. Taking family history into account at SCC diagnosis may help prevention or early detection of SPCs. What's already known about this topic? Second primary cancers (SPCs) are frequently diagnosed in patients with invasive and in situ squamous cell carcinoma (SCC); some epidemiological studies suggest a link to immune dysfunction. Family history of cancer is a risk factor for practically all first primary cancers but whether it also influences risk of SPCs in patients with SCC is not known. The possible influence of family history on survival in patients with SCC remains to be established. Linked Comment: Youlden and Baade. Br J Dermatol 2020; 183:414-415.

Prostate cancer survivors: Risk and mortality in second primary cancers

To assess etiological and clinical consequences of second primary cancers (SPCs) in prostate cancer (PC) patients, we followed newly diagnosed patients to identify men who were diagnosed with a SPC and recorded their causes of death. We used the Swedish Family‐Cancer Database to assess relative risks (RRs) and causes of death in SPCs until the year 2015 in patients with a PC diagnosis between 2001 and 2010. Among a total of 4.26 million men, 76 614 were diagnosed with PC at the median age of 71 years. Among them, 8659 (11.3%) received a subsequent diagnosis of SPC after a median follow‐up of 4 years. The most common SPCs were colorectal, skin, bladder, and lung cancers, melanoma, and non‐Hodgkin lymphoma. The ranking was almost identical with first cancers among elderly men in Sweden. The RR for SPCs in prostate‐specific antigen—detected PC was approximately equal to RR in other PC. Mortality patterns of PC patients were distinct depending on the presence or absence of SPC. Among patients with SPC, 47.8% died as a result of the corresponding SPC, followed by other causes (22.2%) and PC (18.1%). For patients without SPC, PC and non‐neoplastic causes almost matched each other as the main causes of death (48.5% and 47.8%). The results suggest that SPCs appear autonomous from primary PC and reflect incidence and mortality of first cancers in general. SPC was the most common cause of death in patients with SPC; close to half of the patients died due to SPC. For improved survival in PC patients, prevention and early detection of SPCs would be important, and the present results suggest that risk factors for SPC in PC are the same as those for first cancer in general.