MR Imaging in Real Time Guiding of Therapies in Prostate Cancer

The State-of-the-Art and Perspectives of Laser Ablation for Tumor Treatment

Tumors significantly impact individuals' physical well-being and quality of life. With the ongoing advancements in optical technology, information technology, robotic technology, etc., laser technology is being increasingly utilized in the field of tumor treatment, and laser ablation (LA) of tumors remains a prominent area of research interest. This paper presents an overview of the recent progress in tumor LA therapy, with a focus on the mechanisms and biological effects of LA, commonly used ablation lasers, image-guided LA, and robotic-assisted LA. Further insights and future prospects are discussed in relation to these aspects, and the paper proposed potential future directions for the development of tumor LA techniques.

Real-Time and Delayed Imaging of Tissue and Effects of Prostate Tissue Ablation

PURPOSE OF REVIEW

Prostate ablation is increasingly being utilized for the management of localized prostate cancer. There are several energy modalities with varying mechanism of actions which are currently used for prostate ablation. Prostate ablations, whether focal or whole gland, are performed under ultrasound and/or MRI guidance for appropriate treatment plan execution and monitoring. A familiarity with different intraoperative imaging findings and expected tissue response to these ablative modalities is paramount. In this review, we discuss the intraoperative, early, and delayed imaging findings in prostate from the effects of prostate ablation.

RECENT FINDINGS

The monitoring of ablation both during and after the therapy became increasingly important due to the precise targeting of the target tissue. Recent findings suggest that real-time imaging techniques such as MRI or ultrasound can provide anatomical and functional information, allowing for precise ablation of the targeted tissue and increasing the effectiveness and precision of prostate cancer treatment. While intraprocedural imaging findings are variable, the follow-up imaging demonstrates similar findings across various energy modalities. MRI and ultrasound are two of the frequently used imaging techniques for intraoperative monitoring and temperature mapping of important surrounding structures. Follow-up imaging can provide valuable information about ablated tissue, including the success of the ablation, presence of residual cancer or recurrence after the ablation. It is critical and helpful to understand the imaging findings during the procedure and at different follow-up time periods to evaluate the procedure and its outcome.

Suitable T stage for cryosurgery to spare the anus in patients with low rectal cancer

Sphincter preserving therapy is a key research focus for treating low rectal cancer; however, the role of cryotherapy in this process has seldom been reported in the literature. Therefore, we conducted a comprehensive report on the role of cryoablation in sphincter preservation and explored its effect in rectal cancers. An observational study used longitudinal observation and follow-up. Participants were screened from patients whose medical records showed cryotherapy intervention for low rectal cancers from January 2016 to December 2020, with more than 2 years of follow-up. The primary endpoint was progress-free survival, and the secondary outcomes were mainly related to sphincter preservation rate and complications. Thirty-five patients were enrolled in this study, all of whom had their sphincters preserved. Until June 2022, 35 cases achieved long-term progression-free survival (41.77 ± 15.58), with no recurrence observed in 88.57% (31/35) of all patients at follow-up. Cryotherapy showed no significant differences in progress-free survival between sexes (p > 0.05). Cox regression was used to analyze the factors affecting local recurrence, with sex, T stage, size, and cryo-time taken as covariates. The results showed that T stage was a risk factor for local recurrence (p = 0.01, odds ratio: 16.27, 95% confidence interval: 8.20,145.75). Analysis of the T stage according to different subgroups showed that T3 stage was an independent risk factor (p = 0.002). We observed seven cases of complications, which were classified into grades I-II. In patients with low rectal cancers, cryotherapy can safely and effectively preserve the anus and avoid low anterior resection syndrome. Cryoablation has a better curative effect on radical treatment, especially for tumors in the T₀-₂ N₀M₀ stage.