MRI-Guided Lattice Extreme Ablative Dose Radiotherapy For Prostate Cancer

Inclusion criteria

• Biopsy confirmed adenocarcinoma of the prostate.
• T1-T3a disease based on digital rectal exam (DRE).

• T3a disease based on MRI is acceptable (no evidence of frank (clear cut) seminal vesicle (SV) involvement or invasion of bladder or rectum).
• Gleason score 6-10.
• Patients with Gleason score ≥8 must be offered long term androgen deprivation therapy (ADT) and refuse such treatment because only 4-6 months (+/- 2 months) (short term ADT) is permitted (not required) on this protocol. The ADT is recommended to begin after fiducial marker placement; however, ADT is permitted to have been started up to two months prior to the signing of consent. All patients in this protocol may (not required) be treated with 4-6 months (+/- 2 months) of ADT, at the discretion of the treating physician.

• Gleason ≥ 8 must have < 40% of the tissue involved with Gleason 8 in the biopsy specimen.
• Prostate-specific antigen (PSA) ≤ 30 ng/mL within 3 months of enrollment. If PSA was above 30 and dropped to ≤ 30 with antibiotics, this is acceptable for enrollment.
• No previous pelvic radiotherapy.
• No previous history of radical/total prostatectomy (suprapubic prostatectomy is acceptable).
• No concurrent, active malignancy, other than nonmetastatic skin cancer or early stage chronic lymphocytic leukemia (well-differentiated small cell lymphocytic lymphoma). If a prior malignancy is in remission for ≥ 5 years then the patient is eligible.
• Identifiable multiparametric-MRI tumor lesion or lesions, that total in volume < 33% of the prostate

• Multiparametric MRI of prostate and pelvis is required prior to protocol consideration.
• If contrast not given, the point dose on the apparent diffusion coefficient (ADC) map should be < 1000.
• Ability to understand and the willingness to sign a written informed consent document.
• Zubrod performance status < 2.
• Willingness to fill out quality of life forms.
• Bone scan negative if PSA > 15 ng/mL or Gleason ≥ 8 disease. A questionable bone scan is acceptable if other imaging tests are negative for metastasis.
• Serum testosterone is within 40% of normal assay limits (e.g., x=0.4*lower assay limit and x=.04*upper assay limit + upper assay limit), and taken within 4 months of enrollment. Patients who have been started on ADT prior to signing consent are not required to have a serum testosterone at this level prior to signing consent; but, a serum testosterone prior to fiducial marker placement is recommended.
• Serum liver function tests (LFT) are taken within 3 months of enrollment.
• Complete blood counts are taken within 3 months of enrollment.
• Age ≥ 35 and ≤ 85 years.

Exclusion criteria

• > T3a disease on digital rectal exam or >T3a disease clearly identified by MRI.
• Gleason score < 6.
• ≥ 40% Gleason 8-10 tumor, over the total tissue including other tumor and normal tissue. For example: (Gleason 8-10 tumor length/other biopsy tissue length)*100 = ≥ 40%.
• Androgen deprivation therapy longer than 8 months. Androgen deprivation timing is for the Luteinizing hormone-releasing hormone (LHRH) agonist portion only and not when anti-androgen is started beforehand with the purpose of counteracting the surge in testosterone from the LHRH agonist - PSA > 30 ng/mL within 3 months of enrollment.
• PSA > 30 ng/mL within 3 months of enrollment
• Unable to obtain a 1.5T or 3.0T multiparametric MRI of the pelvis and prostate with contrast.
• Unidentifiable multiparametric MRI tumor lesion.
• Identifiable multiparametric-MRI tumor lesions, that total in volume ≥ 33% of the prostate.
• Previous pelvic radiotherapy.
• Previous history of radical prostatectomy.
• Concurrent, active malignancy, which is not nonmetastatic skin cancer or early stage chronic lymphocytic leukemia (well-differentiated small cell lymphocytic lymphoma). If a prior malignancy is in remission for < 5 years then the patient is not eligible.
• Zubrod performance status ≥ 2.
• Inability to understand or unwilling to sign a written informed consent document
• Unwilling to fill out quality of life/psychosocial forms.
• Bone scan is positive and other imaging tests confirm a suspicion of metastasis from prostate cancer.
• Serum testosterone is not within 40% of normal assay limits taken within 4 months of enrollment (only applicable to patients not started on ADT prior to signing consent).
• Serum liver function tests (LFTs) are not taken within 3 months of enrollment.
• Complete blood counts are not taken within 3 months of enrollment.
• Age < 35 and > 85 years.