Curative radiation therapy in prostate cancer

Advancements in nanomedicine: Precision delivery strategies for male pelvic malignancies - Spotlight on prostate and colorectal cancer

BACKGROUND

Pelvic malignancies consistently pose significant global health challenges, adversely affecting the well-being of the male population. It is anticipated that clinicians will continue to confront these cancers in their practice. Nanomedicine offers promising strategies that revolutionize the treatment of male pelvic malignancies by providing precise delivery methods that aim to improve the efficacy of therapeutic outcomes while minimizing side effects. Nanoparticles are designed to encapsulate therapeutic agents and selectively target cancer cells. They can also be loaded with theragnostic agents, enabling multifunctional capabilities.

OBJECTIVE

This review aims to summarize the latest nanomedicine research into clinical applications, focusing on nanotechnology-based treatment strategies for male pelvic malignancies, encompassing chemotherapy, radiotherapy, immunotherapy, and other cutting-edge therapies. The review is structured to assist physicians, particularly those with limited knowledge of biochemistry and bioengineering, in comprehending the functionalities and applications of nanomaterials.

METHODS

Multiple databases, including PubMed, the National Library of Medicine, and Embase, were utilized to locate and review recently published articles on advancements in nano-drug delivery for prostate and colorectal cancers.

CONCLUSION

Nanomedicine possesses considerable potential in improving therapeutic outcomes and reducing adverse effects for male pelvic malignancies. Through precision delivery methods, this emerging field presents innovative treatment modalities to address these challenging diseases. Nevertheless, the majority of current studies are in the preclinical phase, with a lack of sufficient evidence to fully understand the precise mechanisms of action, absence of comprehensive pharmacotoxicity profiles, and uncertainty surrounding long-term consequences.

Immune modulation during anti-cancer radio(immuno)therapy

Cancer can affect all human organs and tissues and ranks as a prominent cause of death as well as an obstruction to increasing life expectancy. A notable breakthrough in oncology has been the inclusion of the immune system in fighting cancer, potentially prolonging life and providing long-term benefits. The concept of "immunotherapy" has been discussed from the 19th and early 20th centuries by Wilhelm Busch, William B. Coley and Paul Ehrlich. This involves distinct approaches, including vaccines, non-specific cytokines and adoptive cell therapies. However, despite the advances made in recent years, questions on how to select the best therapeutic options or how to select the best combinations to improve clinical outcomes are still relevant for scientists and clinicians. More than half of cancer patients receive radiotherapy (RT) as part of their treatment. With the advances in RT and immunotherapy approaches, it is reasonable to consider how to enhance immunotherapy with radiation and vice versa, and to investigate whether combinations of these therapies would be beneficial. In this chapter, we will discuss how the immune system responds to cancer cells and different cancer therapies with a focus on combination of RT and immunotherapy (radioimmunotherapy, RIT).

Complexities of Prostate Cancer

Prostate cancer has a long disease history and a wide variety and uncertainty in individual patients' clinical progress. In recent years, we have seen a revolutionary advance in both prostate cancer patient care and in the research field. The power of deep sequencing has provided cistromic and transcriptomic knowledge of prostate cancer that has not discovered before. Our understanding of prostate cancer biology, from bedside and molecular imaging techniques, has also been greatly advanced. It is important that our current theragnostic schemes, including our diagnostic modalities, therapeutic responses, and the drugs available to target non-AR signaling should be improved. This review article discusses the current progress in the understanding of prostate cancer biology and the recent advances in diagnostic and therapeutic strategies.

Radiotherapy as a tool to elicit clinically actionable signalling pathways in cancer

A variety of targeted anticancer agents have been successfully introduced into clinical practice, largely reflecting their ability to inhibit specific molecular alterations that are required for disease progression. However, not all malignant cells rely on such alterations to survive, proliferate, disseminate and/or evade anticancer immunity, implying that many tumours are intrinsically resistant to targeted therapies. Radiotherapy is well known for its ability to activate cytotoxic signalling pathways that ultimately promote the death of cancer cells, as well as numerous cytoprotective mechanisms that are elicited by cellular damage. Importantly, many cytoprotective mechanisms elicited by radiotherapy can be abrogated by targeted anticancer agents, suggesting that radiotherapy could be harnessed to enhance the clinical efficacy of these drugs. In this Review, we discuss preclinical and clinical data that introduce radiotherapy as a tool to elicit or amplify clinically actionable signalling pathways in patients with cancer.

Prostate cancer

Prostate cancer is a complex disease that affects millions of men globally, predominantly in high human development index regions. Patients with localized disease at a low to intermediate risk of recurrence generally have a favourable outcome of 99% overall survival for 10 years if the disease is detected and treated at an early stage. Key genetic alterations include fusions of TMPRSS2 with ETS family genes, amplification of the MYC oncogene, deletion and/or mutation of PTEN and TP53 and, in advanced disease, amplification and/or mutation of the androgen receptor (AR). Prostate cancer is usually diagnosed by prostate biopsy prompted by a blood test to measure prostate-specific antigen levels and/or digital rectal examination. Treatment for localized disease includes active surveillance, radical prostatectomy or ablative radiotherapy as curative approaches. Men whose disease relapses after prostatectomy are treated with salvage radiotherapy and/or androgen deprivation therapy (ADT) for local relapse, or with ADT combined with chemotherapy or novel androgen signalling-targeted agents for systemic relapse. Advanced prostate cancer often progresses despite androgen ablation and is then considered castration-resistant and incurable. Current treatment options include AR-targeted agents, chemotherapy, radionuclides and the poly(ADP-ribose) inhibitor olaparib. Current research aims to improve prostate cancer detection, management and outcomes, including understanding the fundamental biology at all stages of the disease.

Prostate cancer

Prostate cancer is a complex disease that affects millions of men globally, predominantly in high human development index regions. Patients with localized disease at a low to intermediate risk of recurrence generally have a favourable outcome of 99% overall survival for 10 years if the disease is detected and treated at an early stage. Key genetic alterations include fusions of TMPRSS2 with ETS family genes, amplification of the MYC oncogene, deletion and/or mutation of PTEN and TP53 and, in advanced disease, amplification and/or mutation of the androgen receptor (AR). Prostate cancer is usually diagnosed by prostate biopsy prompted by a blood test to measure prostate-specific antigen levels and/or digital rectal examination. Treatment for localized disease includes active surveillance, radical prostatectomy or ablative radiotherapy as curative approaches. Men whose disease relapses after prostatectomy are treated with salvage radiotherapy and/or androgen deprivation therapy (ADT) for local relapse, or with ADT combined with chemotherapy or novel androgen signalling-targeted agents for systemic relapse. Advanced prostate cancer often progresses despite androgen ablation and is then considered castration-resistant and incurable. Current treatment options include AR-targeted agents, chemotherapy, radionuclides and the poly(ADP-ribose) inhibitor olaparib. Current research aims to improve prostate cancer detection, management and outcomes, including understanding the fundamental biology at all stages of the disease.

Andersen K, Minet LR, Hansen O. Male coping through a long-term cancer trajectory. Secondary outcomes from a RTC examining the effect of a multidisciplinary rehabilitation program (RePCa) among radiated men with prostate cancer

BACKGROUND

The objective of this study was to examine if rehabilitation influenced self-reported male coping styles during and up to three years after treatment with radiotherapy for prostate cancer.

MATERIALS AND METHODS

In a single-center oncology unit in Odense, Denmark, 161 prostate cancer patients treated with radiotherapy and androgen deprivation therapy were included in a randomized controlled trial from 2010 to 2012. The trial examined the effect of a multidisciplinary rehabilitation program within six months of treatment consisting of two nursing counseling sessions and two instructive sessions with a physical therapist (n = 79), or standard care (n = 82). As secondary outcomes coping was measured before radiotherapy, one month after radiotherapy (baseline), six month post-intervention (assessment) and three years after radiotherapy (follow-up) by the Mini-mental adjustment to cancer scale (Mini-MAC). The male coping styles towards the illness are expressed in five mental adjustment styles: Fighting Spirit, Helplessness-Hopelessness, Anxious Preoccupation, Fatalism and Cognitive Avoidance. Descriptive analysis and multiple linear regression analysis adjusting for the longitudinal design were conducted.

RESULTS

Most coping styles remained stable during the patient trajectory but Anxious Preoccupation declined from before radiotherapy to follow-up in both intervention and control groups. After six months the intervention group retained Fighting Spirit significantly (p = 0.025) compared with controls, but after three years this difference evened out. After three years the intervention group had lower Cognitive Avoidance (p = 0.044) than the controls. Factors as educational level, and depression influenced the use of coping styles after three years.

CONCLUSION

Multidisciplinary rehabilitation in irradiated prostate cancer patients retained the adjustment style Fighting Spirit stable after six months of radiotherapy, and in the long term reduced Cognitive Avoidance. Thus, the rehabilitation program supported the patient's active coping style and played down the passive coping style.

Imaging of HER2 may improve the outcome of external irradiation therapy for prostate cancer patients

Prostate cancer (PCa) is the most common type of cancer among males. Human epidermal growth factor receptor type 2 (HER2) expression in PCa has been reported by several studies and its involvement in the progression towards androgen-independent PCa has been discussed. External irradiation is one of the existing therapies, which has been demonstrated to be efficient in combination with androgen deprivation therapy for the treatment of advanced PCa. However, 20–40% of patients develop recurrent and more aggressive PCa within 10 years. The current study investigates the involvement of HER2 in survival and radioresistance in PCa cells and we hypothesized that, by monitoring HER2 expression, treatment may be personalized. The PCa cell lines, LNCap, PC3 and DU-145, received a 6 Gy single dose of external irradiation. The number of PC3 cells was not affected by a single dose of radiation, whereas a 5-fold decrease in cell number was detected in LNCap (P<0.00001) and DU-145 (P<0.0001) cells. The HER2 expression in PC3 exhibited a significant increase post irradiation, however, the expression was stable in the remaining cell lines. The administration of trastuzumab post-irradiation resulted in a 2-fold decrease in the PC3 cell number, while the drug did not demonstrate additional effects in LNCap and DU-145 cells, when compared with that of irradiation treatment alone. The results of the present study demonstrated that an increase in membranous HER2 expression in response to external irradiation may indicate cell radioresistance. Furthermore, imaging of HER2 expression prior to and following external irradiation may present a step towards personalized therapy in PCa.

Adaptive radiotherapy in locally advanced prostate cancer using a statistical deformable motion model

Daily treatment plan selection from a plan library is a major adaptive radiotherapy strategy to account for individual internal anatomy variations. This strategy depends on the initial input images being representative for the variations observed later in the treatment course. Focusing on locally advanced prostate cancer, our aim was to evaluate if residual motion of the prostate (CTV-p) and the elective targets (CTV-sv, CTV-ln) can be prospectively accounted for with a statistical deformable model based on images acquired in the initial part of treatment.

METHODS

Thirteen patients with locally advanced prostate cancer, each with 9-10 repeat CT scans, were included. Displacement vectors fields (DVF) obtained from contour-based deformable registration of delineations in the repeat- and planning CT scans were used to create patient-specific statistical motion models using principal component analysis (PCA). For each patient and CTV, four PCA-models were created: one with all 9-10 DVF as input in addition to models with only four, five or six DVFs as input. Simulations of target shapes from each PCA-model were used to calculate iso-coverage levels, which were converted to contours. The levels were analyzed for sensitivity and precision.

RESULTS

A union of the simulated shapes was able to cover at least 97%, 97% and 95% of the volumes of the evaluated CTV shapes for PCA-models using six, five and four DVFs as input, respectively. There was a decrease in sensitivity with higher iso-coverage levels, with a sharper decline for greater target movements. Apart from having the steepest decline in sensitivity, CTV-sv also displayed the greatest influence on the number of geometries used in the PCA-model.

CONCLUSIONS

PCA-based simulations of residual motion derived from four to six DVFs as input could account for the majority of the target shapes present during the latter part of the treatment. CTV-sv displayed the greatest range in both sensitivity and precision.

Living alone, obesity and smoking: important factors for quality of life after radiotherapy and androgen deprivation therapy for prostate cancer

BACKGROUND

While effective treatment of prostate cancer with radiotherapy and hormones increase survival, adverse effects may reduce quality of life (QoL). The aim of this study was to investigate frequency and severity of self-assessed late adverse effects, and identify the patients most exposed.

MATERIAL AND METHODS

QoL of 317 cancer survivors with primary stage T1-T3 prostate cancer treated with conformal radiotherapy (70-78 Gy) and androgen deprivation therapy was analyzed by using SF-12 and EPIC-26 questionnaires. Patients were stratified into three groups, filling out the questionnaires 1-2, 2-3, and 3-4 years after radiotherapy. Differences between groups were tested with ANOVA and the χ(2) test. The influence of marital status, severe obesity, smoking, stage of disease, and applied dose of radiotherapy on QoL was evaluated with multiple linear and logistic regression analyses.

RESULTS

Of 337 patients, 317 (94%) answered the questionnaire. The sexual and hormonal summary scores in the EPIC significantly improved during time since radiotherapy (p < 0.001). Current smoking had a negative effect on SF-12 Physical Component Summary (PCS) and the Mental Component Summary (MCS) scores, on EPIC bowel overall bother (OR 7.8; p = 0.003), on EPIC mean urinary incontinence scores, and on the sexual domain. Severe obesity had a negative influence on SF-12 PCS and vitality. Severe obesity also was a negative predictor for moderate-to-severe problems in the EPIC urinary incontinence, and in the hormonal domain. Living alone was associated with lower SF-12 PCS, MCS scores, and SF-12 general health, social functioning, and the EPIC hormonal domain. The stage of disease or the radiation dose had no statistically significant impact on QoL.

CONCLUSION

Results showed significant negative associations between smoking, severe obesity and living alone on self-assessed late adverse effects after radiotherapy for prostate cancer. This information may guide rehabilitation.

Patterns of practice in intensity-modulated radiation therapy and image-guided radiation therapy for prostate cancer in Japan

BACKGROUND

The purpose of this study was to compare the prevalence of treatment techniques including intensity-modulated radiation therapy and image-guided radiation therapy in external-beam radiation therapy for prostate cancer in Japan.

METHODS

A national survey on the current status of external-beam radiation therapy for prostate cancer was performed in 2010. We sent questionnaires to 139 major radiotherapy facilities in Japan, of which 115 (82.7%) were returned.

RESULTS

Intensity-modulated radiation therapy was conducted at 67 facilities (58.3%), while image-guided radiation therapy was conducted at 70 facilities (60.9%). Simulations and treatments were performed in the supine position at most facilities. In two-thirds of the facilities, a filling bladder was requested. Approximately 80% of the facilities inserted a tube or encouraged defecation when the rectum was dilated. Some kind of fixation method was used at 102 facilities (88.7%). Magnetic resonance imaging was routinely performed for treatment planning at 32 facilities (27.8%). The median total dose was 76 Gy with intensity-modulated radiation therapy and 70 Gy with three-dimensional radiation therapy. The doses were prescribed at the isocenter at the facilities that conducted three-dimensional radiation therapy. In contrast, the dose prescription varied at the facilities that conducted intensity-modulated radiation therapy. Of the 70 facilities that could perform image-guided radiation therapy, 33 (47.1%) conducted bone matching, 28 (40.0%) conducted prostate matching and 9 (12.9%) used metal markers. Prostate or metal marker matching tended to produce a smaller margin than bone matching.

CONCLUSIONS

The results of the survey identified current patterns in the treatment planning and delivery processes of external-beam radiation therapy for prostate cancer in Japan.