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 Chronic Lymphocytic Leukaemia; Skin, Solid Organ, Haematological, and Richter's Syndrome

Chronic lymphocytic leukaemia (CLL) is invariably accompanied by some degree of immune failure. CLL patients have a high rate of second primary malignancy (SPM) compared to the general population. We comprehensively documented the incidence of all forms of SPM including skin cancer (SC), solid organ malignancy (SOM), second haematological malignancy (SHM), and separately Richter's Syndrome (RS) across all therapy eras. Among the 517 CLL/SLL patients, the overall incidence of SPMs with competing risks were SC 31.07%, SOM 25.99%, SHM 5.19% and RS 7.55%. Melanoma accounted for 30.3% of SC. Squamous cell carcinoma (SCC), including 8 metastatic SCCs, was 1.8 times more than basal cell carcinoma (BCC), a reversal of the typical BCC:SCC ratio. The most common SOM were prostate (6.4%) and breast (4.5%). SHM included 7 acute myeloid leukaemia and 5 myelodysplasia of which 8 were therapy-related. SPMs are a major health burden with 44.9% of CLL patients with at least one, and apart from SC, associated with significantly reduced overall survival. Dramatic improvements in CLL treatment and survival have occurred with immunochemotherapy and targeted therapies but mitigating SPM burden will be important to sustain further progress.

Second Primary Malignancies Among Patients with Multiple Myeloma

Introduction. Treatment for multiple myeloma (MM) has undergone significant transformation in the past decade with the introduction of novel therapeutic agents, including proteasome inhibitors (PI), immunomodulatory imides (IMiD) and monoclonal antibodies (mAb), leading to significant improvements in drug tolerability, treatment response and overall survival. As overall survival improves, patients with MM are at increased risk of developing second primary malignancies. Therefore, we evaluated the incidence of second primary malignancies among patients with MM. Methods. Using data from 30,630 1-year survivors of MM reported to 13 cancer registries that constitute the Surveillance, Epidemiology, and End Results (SEER) program (1992-2015; median survival time, 4.5 years), we calculated standardized incidence ratios (SIR) for all second primary malignancies, any solid and any hematologic malignancy and cancer sites among patients with MM, stratified by calendar year of first primary diagnosis consistent with advances in treatment for MM (1992-1999, 2000-2007, 2008-2015). Individual treatment data were unavailable. Excess absolute risk (excess cancer risk per 10,000 person-years) was calculated as ([observed cancers minus expected cancers]/person-years) multiplied by 10,000. Hazard ratios were calculated using Cox proportional hazards adjusted for confounders. Analyses were conducted using SAS v.9.4. Results. Overall, among 30,630 1-year survivors of first primary MM, the standardized incidence of any second primary malignancy was significantly increased (n=1,962; SIR=1.15, 95% confidence interval [CI], 1.10-1.20; P<0.0001) and SIRs were elevated in each of the three calendar periods (1992-1999, SIR=1.14; 2000-2007, SIR=1.11; 2008-2015, SIR=1.22). Of all the second primary malignancies, the incidence of any solid tumor was increased (n=1,584; SIR=1.05, 95% CI 0.99-1.10; P=0.09), albeit not significantly, with SIRs for specific solid tumor sites ranging from 0.80 to 2.23. In contrast, the incidence of any hematologic malignancy overall was significantly increased (n=317; SIR=2.28, 95% CI 2.03-2.54; P<0.0001) with the largest SIRs observed for any leukemia (SIR=5.86, 95% CI 4.91-6.94; P=<0.0001) and SIRs for leukemia subtypes ranging from 2.07 to 14.87. The SIR for any lymphoma was also increased but to a lesser extent (SIR=1.57, 95% CI 1.35-1.82; P<0.0001). Notably, SIRs for any leukemia decreased over the three time periods (1992-1999, SIR=6.40; 2000-2007, SIR=5.77; 2008-2015, SIR=5.51) whereas SIRs for any lymphoma increased (1992-1999, SIR=1.21; 2000-2007, SIR=1.60; 2008-2015, SIR=1.81) leading to an excess absolute risk of any hematologic malignancy of 1.5 per 10,000 person-years in the latest calendar period. No differences were observed by sex or ancestry. Discussion. We confirm that MM patients are at increased risk of second primary malignancies, and particularly other blood cancers. The transposition of leukemia and lymphoma incidence over time may reflect the effect of treatment changes in recent years. Additional studies, which include individual treatment data and longer follow up time from large and diverse populations, are required to further define these relationships. Disclosures No relevant conflicts of interest to declare.

Second Primary Malignancies in Patients with Pancreatic Neuroendocrine Neoplasms: A Population-Based Study on Occurrence, Risk Factors, and Prognosis

Background. This study aimed to evaluate the risk factors of developing second primary malignancies (SPMs) among patients with pancreatic neuroendocrine neoplasms (pNENs) and the prognosis of pNENs patients with SPMs (pSPMs) using data from the Surveillance, Epidemiology, and End Results (SEER) database. Methods. Data from patients diagnosed with pNENs between 1988 and 2016 were extracted. A case-control study was conducted to investigate the risk factors of developing SPMs among patients with pNENs. Meanwhile, cox regression analysis was also conducted to obtain the independent prognostic factors in pSPMs. Results. Of 7,630 patients with pNENs, 326 developed SPMs. Patients with pNENs who had not undergone surgery and had been diagnosed in recent periods had a higher risk of developing SPMs. The following independent prognostic predictors for pSPMs were identified: age, latency period, SEER stage, radiotherapy, and surgery. Conclusions. These findings may improve the surveillance of risk factors for developing SPMs in patients with pNENs and the prognostic risk factors in pSPMs.

Previous Extrapulmonary Malignancies Impact Outcomes in Patients With Surgically Resected Lung Cancer

Background: As the overall survival of patients with cancer continues to improve, the incidence of second primary malignancies seems to be increasing. Previous studies have shown controversial results regarding the survival of patients with primary lung cancer with previous extrapulmonary malignancies. This study aimed to determine the clinical picture and outcomes of this particular subgroup of patients.Materials and Methods: We included 2,408 patients who underwent pulmonary resection for primary lung cancer at our institute between January 1, 2011 and December 30, 2017 in this retrospective study. Medical records were extracted and clinicopathological parameters and postoperative prognoses were compared between patients with lung cancer with and without previous extrapulmonary malignancies.Results: There were 200 (8.3%) patients with previous extrapulmonary malignancies. Breast cancer (30.5%), gastrointestinal cancer (17%), and thyroid cancer (9%) were the most common previous extrapulmonary malignancies. Age, sex, a family history of lung cancer, and preoperative carcinoembryonic antigen levels were significantly different between the two groups. Patients with previous breast or thyroid cancer had significantly better overall survival than those without previous malignancies. Conversely, patients with other previous extrapulmonary malignancies had significantly poorer overall survival (p < 0.001). The interval between the two cancer diagnoses did not significantly correlate with clinical outcome.Conclusion: Although overall survival was lower in patients with previous extrapulmonary malignancies, previous breast or thyroid cancer did not increase mortality. Our findings may help surgeons to predict prognosis in this subgroup of patients with primary lung cancer.

Non-Prostate Cancer Tumours: Incidence on 18f-Dcfpyl Psma Pet/Ct and Psma Expression Characteristics in 1445 Patients.

PurposeProstate cancer (PCa) imaging has been revolutionized by Positron emission tomography (PET) tracers targeted to prostate specific membrane antigen (PSMA). Identification and characterization of non-PCa tumors has become an increasing clinical dilemma with growing use. The primary aim of this retrospective multicenter analysis was to determine atypical PSMA expression in PCa and expression in non-PCa tumors to aid providing clinically relevant reports and guiding multidisciplinary discussion.MethodsRetrospective multicenter study examining 1445 consecutive 18F-DCFPyL PSMA PET/CT between 2016-2020. Referrals were from public and private, secondary and tertiary referral centres serving New Zealand and Melbourne. Repeat studies were excluded. Lesions atypical for PCa were categorized into four groups: 1. Atypical PCa metastases 2. Non-PCa tumors 3. Benign and 4. Indeterminate.Results67 patients had lesions atypical for PCa metastases; 11.9% atypical prostate cancer metastases, 25.4% non-PCa tumors, 40.3% indeterminate, 10.4% benign. With the exception of Renal Cell Carcinoma (RCC), the non-PCa tumors, indeterminate and benign lesions demonstrated low PSMA expression. Most atypical PCa metastases demonstrated significant expression. Limitations included retrospective design and lack of histopathological correlation/follow up in some.Conclusions: Non-PCa tumor detection is low. Lesions demonstrating significant PSMA expression were almost exclusively PCa metastases. Differentiation of atypical PCa metastases from second primary malignancies is vital to avoid unnecessary investigation, delayed therapy and additional costs.