Challenges and Opportunities in Radiation-induced Hemorrhagic Cystitis

Slightly photo-crosslinked chitosan/silk fibroin hydrogel adhesives with hemostasis and anti-inflammation for pro-healing cyclophosphamide-induced hemorrhagic cystitis

Cyclophosphamide is commonly used in the treatment of various cancers and autoimmune diseases, while concurrently imposing substantial toxicity on the bladder, frequently manifesting hemorrhagic cystitis. Intravesical interventions, such as hyaluronic acid supplementation, present a therapeutic strategy to reinstate bladder barrier function and alleviate the effects of metabolic toxicants. However, it remains a great challenge to achieve efficient cyclophosphamide-induced hemorrhagic cystitis (CHC) management with accelerated tissue repair owing to the low wet-adhesion, poor hemostasis, and acute inflammatory responses. To address these issues, a hemostatic and anti-inflammatory hydrogel adhesive of chitosan methylacryloyl/silk fibroin methylacryloyl (CHMA/SFMA) is developed for promoting the healing of CHC. The obtained hydrogels show a high adhesive strength of 26.21 N/m with porcine bladder, facilitating the rapid hemostasis within 15 s, and reinstate bladder barrier function. Moreover, this hydrogel adhesive promotes the proliferation and aggregation of SV-HUC-1 and regulates macrophage polarization. Implanting the hydrogels into CHC bladders of a SD rat model, they not only can be completely biodegraded in 14 days, but also effectively control hematuria and inflammation, and accelerate angiogenesis, thereby significantly promote the healing of bladder injury. Overall, CHMA/SFMA hydrogels exhibit rapid hemostasis for treating CHC and accelerate muscle tissue repair via angiogenesis and inflammation amelioration, which may provide a new path for managing severe hemorrhagic cystitis in the clinics.

The effect of myeloablative radiation on urinary bladder mast cells

Radiation-induced cystitis is an inflammatory condition affecting the urinary bladder, which can develop as a side effect of abdominopelvic radiotherapy, specifically external-beam radiation therapy or myeloablative radiotherapy. A possible involvement of mast cells in the pathophysiology of radiation-induced cystitis has been indicated in cases of external-beam radiation therapy; however, there is no evidence that these findings apply to the myeloablative aetiology. As such, this study investigated potential changes to urinary bladder mast cell prevalence when exposed to myeloablative radiation. Lethally irradiated C57BL/6J mice that received donor rescue bone marrow cells exhibited an increased mast cell frequency amongst host leukocytes 1 week following irradiation. By 4 weeks, no significant difference in either frequency or cell density was observed. However mast cell diameter was smaller, and a significant increase in mast cell number in the adventitia was observed. This study highlights that mast cells constitute a significant portion of the remaining host leukocyte population following radiation exposure, with changes to mast cell distribution and decreased cell diameter four weeks following radiation-induced injury.

The effects of radiation on myeloid lineage immune cells within the rodent urinary bladder: a systematic review

PURPOSE

Radiotherapy is a prominent therapy for many malignant and non-malignant disorders, though it can cause side effects such as radiation-induced cystitis. Current research has highlighted a role for mast cells and macrophages in the prognosis of such radiation-induced toxicities. However, the prognostic value of these immune cells in the pathophysiology of radiation-induced cystitis is not clear. As such, a systematic review was conducted to assess myeloid-lineage immune cells for their prognostic value in radiation-induced cystitis to address this gap in literature.

METHODS

The protocol was registered in PROSPERO, and searches were performed in PubMed, Embase and Web of Science databases for pre-clinical rodent studies on radiation-induced cystitis.

RESULTS

After de-duplication, 153 articles were screened for relevancy by title and abstract. Title and abstract screening deemed 64 studies irrelevant. The remaining 85 studies were full-text screened, yielding seven unique articles for data extraction. Most included studies had an unclear risk of bias. The findings of this systematic review suggest that the prognostic value of myeloid-lineage immune cells in radiation-induced cystitis is still unclear, indicating a need for further research in this field.

CONCLUSION

Although the studies reviewed provide some insight into the role of these immune cells in disease pathology, the limited number of studies and unclear risk of bias further highlights a need for additional, high-quality research in this area. In summary, this systematic review highlights a need to understand the involvement of immune cells in radiation-induced cystitis pathophysiology and lay the groundwork for further research in this area.

TRIAL REGISTRATION

PROSPERO registration: CRD42022345960.

Analysis of Clinicopathological Factors Associated with Radiation-Induced Cystitis in Patients with Cervical Cancer

Objective

To analyze the clinicopathological characteristics associated with radiation-induced cystitis (RIC) in patients with cervical cancer treated with chemoradiotherapy (CRT) alone or postoperational (post-op) CRT.

Methods

107 patients with cervical cancer were retrospectively recruited into the study. The surgical status, FIGO staging, total and fractionated doses of radiotherapy (RT), and multiparameters including the dose, volume irradiated to the total bladder, and bladder wall were evaluated for RIC. The criteria on RIC were referred to CTCAE v5.0.

Results

Surgical operation and post-op CRT were delivered in 65 patients and CRT or RT alone in 42 patients. Among those with post-op CRT, 33/34 (97.06%), 22/43 (51.16%), and 10/30 (33.33%) patients were classified as FIGO stage I, II, and III/IV, respectively. The incidence of RIC was 30.84% for the whole group with 87.87% occurred in stage I and II patients. The incidence of CTCAE grade 2 and beyond was significantly higher in patients treated with post-op CRT than those with CRT alone (13.85% vs 2.38%, p = 0.043). Further analyses showed that the CTCAE level of RIC in the post-op CRT group was related to the relatively smaller average bladder volume (p = 0.029), whereas the difference in volume of bladder and bladder wall irradiated to 35.0 Gy or 40.0 Gy was not statistically significant between patients with or without RIC. Conclusion. The combination of surgery and post-op CRT may increase the incidence and severity of radiation-induced cystitis when compared to CRT alone, suggesting that bladder dysfunction associated with surgical procedure might increase the frequency and severity radiation related bladder toxicity. Further study is merited.

Cumulative Incidence and Clinical Risk Factors of Radiation Cystitis after Radiotherapy for Prostate Cancer

OBJECTIVES

This study aimed to evaluate the cumulative incidence of overall and severe radiation cystitis following external beam radiation therapy for prostate cancer and investigate the clinical factors predictive of radiation cystitis.

METHODS

This retrospective study comprised 246 patients who received external beam radiation therapy for localized or locally advanced prostate cancer between 2013 and 2016 in our institution. Of these, 189 received primary radiation therapy and 57 received adjuvant/salvage radiation therapy. Radiation cystitis was recorded using the Common Terminology Criteria for Adverse Events version 5.0 definition, and severe radiation cystitis was defined as grade 3 or higher. All medical records were reviewed to calculate the cumulative incidence of radiation cystitis. Univariate and multivariate Cox regression analyses were used to evaluate its association with clinicopathologic features.

RESULTS

The median follow-up period after radiation therapy was 56 months (range 5-81). The 5-year cumulative incidence of radiation cystitis and severe radiation cystitis was 16.2% and 3.0%, respectively. Multivariate analyses identified radiation therapy in the adjuvant/salvage setting was the sole risk factor associated with the development of radiation cystitis (hazard ratio: 2.75, p = 0.02).

CONCLUSIONS

Radiation therapy in the post-prostatectomy setting was associated with increased risk of radiation cystitis compared with radiotherapy as the primary treatment.

Voiding defects in acute radiation cystitis driven by urothelial barrier defect through loss of E-cadherin, ZO-1 and Uroplakin III

Long term-side effects from cancer therapies are a growing health care concern as life expectancy among cancer survivors increases. Damage to the bladder is common in patients treated with radiation therapy for pelvic cancers and can result in radiation (hemorrhagic) cystitis (RC). The disease progression of RC consists of an acute and chronic phase, separated by a symptom-free period. Gaining insight in tissue changes associated with these phases is necessary to develop appropriate interventions. Using a mouse preclinical model, we have previously shown that fibrosis and vascular damage are the predominant pathological features of chronic RC. The goal of this study was to determine the pathological changes during acute RC. We identified that radiation treatment results in a temporary increase in micturition frequency and decrease in void volume 4–8 weeks after irradiation. Histologically, the micturition defect is associated with thinning of the urothelium, loss of urothelial cell–cell adhesion and tight junction proteins and decrease in uroplakin III expression. By 12 weeks, the urothelium had regenerated and micturition patterns were similar to littermate controls. No inflammation or fibrosis were detected in bladder tissues after irradiation. We conclude that functional bladder defects during acute RC are driven primarily by a urothelial defect.

Management of Medium and Long Term Complications Following Prostate Cancer Treatment Resulting in Urinary Diversion - A Narrative Review

The purpose of this narrative review is to discuss and highlight recently published studies regarding the surgical management of patients suffering from prostate cancer treatment complications. Focus will be put on the recalcitrant and more complex cases which might lead to urinary diversion as a definite, last resort treatment. It is in the nature of every treatment, that complications will occur and be bothersome for both patients and physicians. A small percentage of patients following prostate cancer treatment (radical prostatectomy, radiation therapy, or other focal therapies) will suffer side effects and thus, will experience a loss of quality of life. These side effects can persist for months and even years. Often, conservative management strategies fail resulting in recalcitrant recurrences. Prostate cancer patients with "end-stage bladder," "devastated outlet," or a history of multiple failed interventions, are fortunately rare, but can be highly challenging for both patients and Urologists. In a state of multiple previous surgical procedures and an immense psychological strain for the patient, urinary diversion can offer a definite, last resort surgical solution for this small group of patients. Ideally, they should be transferred to centers with experience in this field and a careful patient selection is needed. As these cases are highly complex, a multidisciplinary approach is often necessary in order to guarantee an improvement of quality of life.

Prostate cancer survivors with symptoms of radiation cystitis have elevated fibrotic and vascular proteins in urine

Radiation for pelvic cancers can result in severe bladder damage and radiation cystitis (RC), which is characterized by chronic inflammation, fibrosis, and vascular damage. RC development is poorly understood because bladder biopsies are difficult to obtain. The goal of this study is to gain understanding of molecular changes that drive radiation-induced cystitis in cancer survivors using urine samples from prostate cancer survivors with history of radiation therapy. 94 urine samples were collected from prostate cancer survivors with (n = 85) and without (n = 9) history of radiation therapy. 15 patients with radiation history were officially diagnosed with radiation cystitis. Levels of 47 different proteins were measured using Multiplex Luminex. Comparisons were made between non-irradiated and irradiated samples, and within irradiated samples based on radiation cystitis diagnosis, symptom scores or hematuria. Statistical analysis was performed using Welch’s t-test. In prostate cancer survivors with history of radiation therapy, elevated levels of PAI 1, TIMP1, TIMP2, HGF and VEGF-A were detected in patients that received a radiation cystitis diagnosis. These proteins were also increased in patients suffering from hematuria or high symptom scores. No inflammatory proteins were detected in the urine, except in patients with gross hematuria and end stage radiation cystitis. Active fibrosis and vascular distress is detectable in the urine through elevated levels of associated proteins. Inflammation is only detected in urine of patients with end-stage radiation cystitis disease. These results suggest that fibrosis and vascular damage drive the development of radiation cystitis and could lead to the development of more targeted treatments.

Treatment protocols for BK virus associated hemorrhagic cystitis after hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) represents a vital curative choice for many disease. However its outcome can be hampered by a variety of transplant associated complications. Hemorrhagic cystitis (HC) considered as one of the major difficulties after HSCT. HC symptoms comprise hematuria, dysuria, burning during urination, urinary frequency, urgency and incontinency, abdominal or suprapubic pain, urinary obstruction, and renal or bladder damage. There are a lot of causes for HC development. BK virus reactivation is one of the major causes of HC after HSCT. There is still no standard and approved treatment protocol for BK virus associated HC (BKV-HC). Treatment of HC is according to the local standard operating procedures, depending on the cause and severity. In this study we will review the current treatments available for this disease. We have divided the therapeutic procedures into 5 categories including conservative therapy, complimentary options, surgical procedures, pharmacological treatments and adoptive cell therapy. We believe that comparing the advantages and disadvantages of different therapies make it easier to choose the best treatment protocol. In addition, we had a greater focus on adoptive cell therapy, because it is a relatively new introduced method and might be a logical alternative to conventional treatments for refractory patients. In total, no definitive recommendation is possible for current available treatments because these procedures have only been utilized sporadically in a limit number of patients. Furthermore, a number of treatment options are only experimental and definitely need more effort.

Endovascular Management of Radiation-Induced Hemorrhagic Cystitis

Radiation-induced hemorrhagic cystitis (HC) is an unpleasant and sometimes life-threatening complication confronted while treating pelvic malignancies. A wide array of treatment modalities such as bladder irrigation, fulguration, hyperbaric oxygen therapy, and surgical methods has been proposed to treat hematuria, but there is no consensus on the optimal therapeutic strategy for the same. Reported here is a successful superselective embolization of the bilateral vesical arteries in a patient with refractory radiation-induced HC. This technique proved to be effective in controlling intractable hemorrhage and can be considered an option for the treatment of HC not amenable to conventional techniques.

Cancer survivorship issues with radiation and hemorrhagic cystitis in gynecological malignancies

PURPOSE

Given that more cancers are being diagnosed earlier and that treatment of cancer is improving, health issues of cancer survivors are becoming more common and apparent. Pelvic radiation therapy for the treatment of gynecological cancers can lead to long-term collateral damage to the bladder, a condition termed radiation cystitis (RC). Late sequelae may take many years to develop and include incontinence and pain as well as hematuria. RC is a rare but potentially life-threatening condition for which there are few management and treatment options.

METHODS

There are limited data in the literature regarding the effects of radiation on the bladder after gynecological cancer therapy and we hereby review the literature on cancer survivorship issues of pelvic radiation for gynecology literature.

RESULTS

Treatment options are available for patients with radiation-induced hemorrhagic cystitis. However, most treatments are risky or only effective for a short timeframe and no therapy is currently available to reverse the disease progress. Furthermore, no standardized guidelines exist describing preferred management options. Common therapies include hyperbaric oxygen therapy, clot evacuation, fulguration, intravesical instillation of astringent agents, and surgery. Novel developing strategies include Botulinum Toxin injections and liposomal-tacrolimus instillations. These treatments and strategies are discussed.

CONCLUSIONS

In this review, we will present current and advanced therapeutic strategies for RC to help cancer survivors deal with long-term bladder health issues.

Altered Angiogenic Growth Factors in Urine of Prostate Cancer Survivors With Radiation History and Radiation Cystitis

OBJECTIVE

To determine if the vascular damage in bladders of prostate cancer (PCa) survivors with radiation cystitis can be detected through altered angiogenic growth factors in urine.

METHODS

Urine samples from PCa survivors with a history of external beam radiation therapy were tested for a panel of angiogenic growth factors by Luminex assay. Urine creatinine levels were measured through high performance liquid chromatography. Through a patient survey, data on patient demographics, radiation history, and urinary symptoms were collected.

RESULTS

Hepatocyte growth factor (HGF), placental growth factor (PlGF), and vascular endothelial growth factor (VEGF) were altered in urine of PCa survivors with a history of radiation therapy. HGF and PlGF were elevated in response to irradiation, while VEGF had a decreasing trend. Within the irradiated population, HGF was also increased in patients diagnosed with radiation cystitis and patients with hematuria. PlGF and VEGF were only increased in the first year postirradiation, and VEGF was elevated in patients with hematuria. Finally, creatinine levels were increased in PCa survivors with a history of radiation therapy.

CONCLUSION

Radiation cystitis is a debilitating bladder condition that cancer survivors are at risk of developing after pelvic radiation. In this study, we identified 3 pro-angiogenic factors that may be urine biomarkers and, if validated in future studies, could indicate new strategy approaches to treat radiation cystitis.

Disease- and Treatment-related Complication on F-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Oncology Practice: A Pictorial Review

F-18-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is routinely performed in oncology patients for various indications including staging, restaging, recurrence detection, and treatment response evaluation. Many disease- and treatment-related complications can be incidentally detected on PET/CT, which may be due to the complication of radiotherapy, chemotherapy, intervention, or primary tumor itself. Some of these complications could be life threatening and need urgent intervention. Therefore, these incidental findings should be recognized on PET/CT and immediately informed to the treating physicians if required urgent intervention.

Treatment of Severe Refractory Hematuria due to Radiation-Induced Hemorrhagic Cystitis with Dexamethasone

Treatment of pelvic neoplasms with radiotherapy may develop sequelae, especially RHC. An 85-year-old male patient was admitted to a hospital emergency with gross hematuria leading to urinary retention and was diagnosed with RHC. The urinary bladder was probed, unobstructed, and maintained in continuous three-way saline irrigation. During 45 days of hospitalization, the patient underwent two cystoscopic procedures for urinary bladder flocculation, whole blood transfusions, and one platelet apheresis. None of these interventions led to clinical resolution. As the patient hematological condition was deteriorating, dexamethasone (4 mg i.v., bolus of 6/6, 12/12, and 24 h during five days) and epoetin alpha (1000 IU, 1 ml, s.c., for four weeks) were administered which led to the remission of the urinary bleeding. Dexamethasone therapy may be considered for RHC, when conventional treatments are not effective or are not possible, avoiding more aggressive interventions such as cystectomy.