Carboplatin Chemotherapy Before Surgery for People With High-Risk Prostate Cancer and an Inherited BRCA1 or BRCA2 Gene Mutation

S2210 A Phase II Study of Neoadjuvant Carboplatin for Localized, High Risk Prostate Cancer With Germline BRCA1/2 Mutations

This phase II trial tests how well carboplatin before surgery works in treating patients with high-risk prostate cancer and an inherited BRCA1 or BRCA2 gene mutation. Carboplatin is in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping, or slowing the growth of tumor cells. Giving carboplatin before surgery may shrink tumors in patients with high-risk prostate cancer with BRCA1 and BRCA2 gene mutations.

PRIMARY OBJECTIVE:

I. To evaluate the pathologic complete response rate at prostatectomy in patients with localized high-risk prostate cancer with germline BRCA2 or BRCA1 mutations who are treated with neoadjuvant carboplatin by central review of source documents.

SECONDARY OBJECTIVES:

I. To evaluate prostate specific antigen (PSA) progression-free survival post-prostatectomy over the duration of follow-up and specifically, at the 3-year landmark.

II. To evaluate metastases free survival and overall survival. III. To evaluate the frequency and severity of toxicities of neoadjuvant carboplatin followed by radical prostatectomy.

BANKING OBJECTIVE:

I. To bank specimens for future correlative studies.

OUTLINE:

Patients receive carboplatin intravenously (IV) on study. Patients then undergo surgery on study. Patients who experience PSA progression after surgery undergo computed tomography (CT) or magnetic resonance imaging (MRI) of the abdomen and pelvis, CT of the chest or chest X-ray, or prostate-specific membrane antigen (PSMA)-positron emission tomography (PET) throughout the trial. Patients also undergo collection of blood samples throughout the trial.

Inclusion Criteria:

• Participant must have histologic diagnosis of prostate adenocarcinoma

• Participant must have high or very high-risk disease defined by at least one of the following:

  • cT3a - cT4x
  • Grade group 4 or 5 (Gleason sum 8-10)
  • PSA > 20 ng/mL prior to registration

• Participant must have documented evidence of germline mutation (pathogenic/likely pathogenic variant) in BRCA2 or BRCA1 through testing in a Clinical Laboratory Improvement Act (CLIA)-certified lab

  • NOTE: Local lab report is sufficient for eligibility

• Participant may have initiated gonadotrophin releasing hormone (gnRH) agonist, gnRH antagonist, oral anti-androgen (e.g. bicalutamide, nilutamide, flutamide), or other agent intended to treat prostate cancer prior to registration. The effectiveness of the current depot of such treatment must not extend beyond 1 month after study registration. Agents listed above cannot be started after participant registration

• Participant must be >= 18 years old

• Participant must have Zubrod performance status of 0-2

• Participant must have a complete medical history and physical exam within 28 days prior to registration

• Absolute neutrophil count >= 1.5 x 10^3/uL (within 28 days prior to registration)

• Platelets >= 100 x 10^3/uL (within 28 days prior to registration)

• Aspartate aminotransferase (AST)/alanine aminotransferase (ALT) =< 3 x institutional upper limit of normal (ULN) (within 28 days prior to registration)

• Participant must have a serum creatinine =< the institutional upper limit of normal (IULN) OR measured OR calculated creatinine clearance >= 50 mL/min using the following Cockcroft-Gault Formula. This specimen must have been drawn and processed within 28 days prior to registration

• Participant must have adequate cardiac function. Participants with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, must have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification within 28 days prior to registration. To be eligible for this trial, participants must be class 2B or better

• Participant with known human immunodeficiency virus (HIV)-infection must be receiving anti-retroviral therapy and have an undetectable viral load test within 6 months prior to registration

• Participant with history of chronic hepatitis B virus (HBV) infection must have undetectable HBV viral load on suppressive therapy within in 28 days prior to registration

• Participant with a history of hepatitis C virus (HCV) infection must have been treated and cured. For participants with HCV infection who are currently on treatment must have an undetectable HCV viral load within in 28 days prior to registration

• Participants who are of reproductive potential must have agreed to use an effective contraceptive method with details provided as a part of the consent process. A person who has semen likely to contain sperm is considered to be of "reproductive potential." In addition to routine contraceptive methods, "effective contraception" also includes refraining from sexual activity that might result in pregnancy and surgery intended to prevent pregnancy (or with a side-effect of pregnancy prevention) including vasectomy with testing showing no sperm in the semen

• Prior to registration, participant must have had a urologic consult and be deemed a surgical candidate with known sites of disease deemed by the urologist to be potentially resectable

• Participants must be offered the opportunity to participate in specimen banking. With participant consent, specimens must be collected and submitted via the Southwest Oncology Group (SWOG) Specimen Tracking System

• NOTE: As a part of the OPEN registration process the treating institution's identity is provided in order to ensure that the current (within 365 days) date of institutional review board approval for this study has been entered in the system

  • Participants must be informed of the investigational nature of this study and must sign and give informed consent in accordance with institutional and federal guidelines
  • For participants with impaired decision-making capabilities, legally authorized representatives may sign and give informed consent on behalf of study participants in accordance with applicable federal, local, and Central Institutional Review Board (CIRB) regulations
  • As part of the registration process the treating institution's identity is provided in order to ensure that the current (within 365 days) date of institutional review board approval for this study has been entered in the system

Exclusion Criteria:

• Participant must not have evidence of distant metastatic disease by conventional imaging within 90 days prior to registration

  • NOTE: cN1 detected only by PSMA-PET is permitted if urologist deems sites of disease to be potentially completely resectable

• Participant must not have received prior radiation therapy (RT) to the pelvic region

• Participant must not have a prior or concurrent malignancy whose natural history or treatment (in the opinion of the treating physician) has the potential to interfere with the safety or efficacy assessment of protocol treatment