NCCN Guidelines Insights: Prostate Cancer, Version 1.2021.

The NCCN Guidelines for Prostate Cancer address staging and risk assessment after a prostate cancer diagnosis and include management options for localized, regional, and metastatic disease. Recommendations for disease monitoring and treatment of recurrent disease are also included. The NCCN Prostate Cancer Panel meets annually to reevaluate and update their recommendations based on new clinical data and input from within NCCN Member Institutions and from external entities. This article summarizes the panel's discussions for the 2021 update of the guidelines with regard to systemic therapy for metastatic castration-resistant prostate cancer.

A pilot study of endorectal magnetic resonance imaging and magnetic resonance spectroscopic imaging changes with dutasteride in patients with low risk prostate cancer.

OBJECTIVE: •To evaluate the effects of dutasteride on treatment-naïve prostate cancer in men using serial magnetic resonance imaging (MRI) and magnetic resonance spectroscopic imaging (MRSI) in this pilot study. PATIENTS AND METHODS: •This investigator-initiated prospective single-arm study was approved by the institutional committee on human research ethics board. •The target accrual was 10 patients. Newly diagnosed prostate cancer patients with low risk disease either with symptomatic benign prostatic hypertrophy or deemed to require pre-brachytherapy androgen suppression therapy were eligible. In the latter group, dutasteride was used to achieve cytoreduction. •All patients received 6 months of dutasteride 3.5 mg daily and underwent baseline blood work, health-related quality of life indices and MRI/MRSI, which were repeated at 1, 3 and 6 months. •MRSI spectra were examined and scored as healthy or cancerous. The change in cancerous volumes over time was evaluated. RESULTS: •Of the 10 patients enrolled, nine patients completed the entire study. One patient withdrew after 3 months because of drug-related toxicity. •Because a significant decrease in citrate and polyamines on MRSI spectra was noted at 1 month compared with baseline, healthy tissue appeared to be more like cancer and thus created a false impression that the cancer had grown after 1 month. To reduce this bias, comparisons were made between the 1-month and 6-month scans. •The median MR cancer volumes at 6 months and 3 months were 100% and 101% of the 1-month value, respectively. Three of the nine patients had a 30-45% decrease in cancer volume at 6 months relative to 1-month measures. Of the others, two had no change in cancer volume and four had an increase (range 65-167% of the 1-month value). •The median cancer volume (range) at baseline was only 0.5 (0.1-5.6) mL. CONCLUSIONS: •The inclusion of only men with low volume disease may have limited our ability to accurately assess response rates after dutasteride due to the background effects on normal prostate metabolism. Despite this, one-third of patients had a 30-45% reduction in cancer volume at 6 months. •Future studies including men with larger volume disease may enable estimates of response rates to be made more accurately.

Toward adaptive stereotactic robotic brachytherapy for prostate cancer: demonstration of an adaptive workflow incorporating inverse planning and an MR stealth robot.

To translate any robot into a clinical environment, it is critical that the robot can seamlessly integrate with all the technology of a modern clinic. MRBot, an MR-stealth brachytherapy delivery device, was used in a closed-bore 3T MRI and a clinical brachytherapy cone beam CT suite. Targets included ceramic dummy seeds, MR-Spectroscopy-sensitive metabolite, and a prostate phantom. Acquired DICOM images were exported to planning software to register the robot coordinates in the imager's frame, contour and verify target locations, create dose plans, and export needle and seed positions to the robot. The coordination of each system element (imaging device, brachytherapy planning system, robot control, robot) was validated with a seed delivery accuracy of within 2 mm in both a phantom and soft tissue. An adaptive workflow was demonstrated by acquiring images after needle insertion and prior to seed deposition. This allows for adjustment if the needle is in the wrong position. Inverse planning (IPSA) was used to generate a seed placement plan and coordinates for ten needles and 29 seeds were transferred to the robot. After every two needles placed, an image was acquired. The placed seeds were identified and validated prior to placing the seeds in the next two needles. The ability to robotically deliver seeds to locations determined by IPSA and the ability of the system to incorporate novel needle patterns were demonstrated. Shown here is the ability to overcome this critical step. An adaptive brachytherapy workflow is demonstrated which integrates a clinical anatomy-based seed location optimization engine and a robotic brachytherapy device. Demonstration of this workflow is a key element of a successful translation to the clinic of the MRI stealth robotic delivery system, MRBot.

Mapping of lymphatic drainage from the prostate using filtered 99mTc-sulfur nanocolloid and SPECT/CT.

UNLABELLED: We have developed a practice procedure for prostate lymphoscintigraphy using SPECT/CT and filtered (99m)Tc-sulfur nanocolloid, as an alternative to the proprietary product (99m)Tc-Nanocoll, which is not approved in the United States. METHODS: Ten patients were enrolled for this study, and all received radiotracer prepared using a 100-nm membrane filter at a commercial radiopharmacy. Whole-body scans and SPECT/CT studies were performed within 1.5-3 h after the radiotracer had been administered directly into 6 locations of the prostate gland under transrectal ultrasound guidance. The radiation dose was estimated from the first 3 patients. Lymphatic drainage mapping was performed, and lymph nodes were identified. RESULTS: The estimated radiation dose ranged from 3.9 to 5.2 mSv/MBq. The locations of lymph nodes draining the prostate gland were similar to those found using the proprietary product. CONCLUSION: When the proprietary radiolabeled nanocolloid indicated for lymphoscintigraphy is not available, prostate lymph node mapping and identification are still feasible using filtered (99m)Tc-sulfur nanocolloid.