Second Primary Cancers in Patients With Castration Resistant Prostate Cancer

This study aims at estimating the incidence of second primary malignancies as well as the overall survival among mPC and mCRPC patients not treated with radium-223-dichloride. The source of data for this study will be the German Pharmacoepidemiological Research Database (GePaRD). A retrospective cohort study covering the time period from 2004 to 2013 will be conducted. The study population will comprise CRPC patients developing bone metastases. These patients will be followed up for the occurrence of second primary malignancies, end of study, or death due to any cause. As this study serves as a historical control group for a single-arm observational study, incidence rates of second primary malignancies obtained from these studies will be compared by the standardized incidence ratio using results from this study as a reference.

Inclusion criteria

• Members of the mPC cohort will have to fulfill all of the following criteria:

• Valid information on sex, age and the region of residence
• A period of at least 12 months of continuous insurance preceding cohort entry
• Diagnosis of PC (ICD-10 Code C61) in the study period (01-Jan-2004 to 31-Dec-2011)
• Diagnosis of bone metastases (ICD-10 Code C79.5) in the enrolment period (01-Jan-2005 to 31-Dec-2011)
• In addition to the criteria of the mPC cohort, members of the mCRPC will additionally have to fulfill:
• One of the following in the enrolment period and before or at the same time with bone metastases

• Discontinuation of the initial chemical castration, change of the agent or modality of the Androgen deprivation therapy (ADT), or start of treatment for advanced Prostate cancer (PC) after the primary ADT.
• Surgical castration and initiation of ADT treatment
• Treatment with medication specific to mCRPC.

Exclusion criteria

• Patients will be excluded from the mPC and from the mCRPC populations if they meet one of the following criteria:

• First PC diagnosis later than 2 months after the diagnosis of bone metastases, or
• Use of any radiopharmaceuticals for bone metastases (e.g., samarium, strontium, rhenium, radium)