Trimodality treatment for bladder cancer: does modern radiotherapy improve the end results?

Urinary schistosomiasis and the associated bladder cancer: update

Background

Urinary schistosomiasis and its severe complications, mainly bladder cancer, are scarce in non-endemic areas. The deficiency in knowledge and clinical experience of schistosomiasis may lead to inadequate management. Highlighting these topics may be of value, especially with the increased immigration from endemic low-/middle-income countries (LMIC) to non-endemic high-income countries (HIC). Schistosomiasis is a parasitic infection endemic in many low- and middle-income countries. It can affect various systems but is best known for its effect on the urinary system.

Main Body

PubMed, Scopus, Google Scholar, and the Cochrane Library databases were searched for urinary schistosomiasis and its related bladder cancer published from 1980 till 2020.

Schistosoma haematobium (SH) infecting the urinary bladder was considered by the IARC as group 1 definitive biological carcinogenic agent. Several carcinogenic pathways have been postulated but the exact mechanism(s) are not defined yet. A more thorough understanding of the parasite life cycle was explored to help eradicate the infection especially for the immigrants from endemic areas. This may prevent or slow down the process of carcinogenesis that leads to Schistosoma-associated bladder cancer (SA-BC), which is usually, but not conclusively, squamous cell carcinoma. Treatment of SA-BC generally follows the same guidelines as urothelial Schistosoma-non-associated bladder cancer (SNA-BC) management; however, prospective trials to confirm and refine the treatment approach for SA-BC have been relatively limited.

Conclusion

The available data showed that despite some etiologic and carcinogenic differences, the oncologic outcomes are generally comparable for SA-BC and NSA-BC when adjusting for stage, risk status, and comorbidities.

Endoscopic gold fiducial marker placement into the bladder wall to optimize radiotherapy targeting for bladder-preserving management of muscle-invasive bladder cancer: feasibility and initial outcomes

Background and Purpose

Bladder radiotherapy is a management option for carefully selected patients with muscle-invasive bladder cancer. However, the inability to visualize the tumor site during treatment and normal bladder movement limits targeting accuracy and increases collateral radiation. A means to accurately and reliably target the bladder during radiotherapy is needed.

Materials and Methods

Eighteen consecutive patients with muscle-invasive bladder cancer (T1–T4) elected bladder-preserving treatment with maximal transurethral resection (TUR), radiation and concurrent chemotherapy. All underwent endoscopic placement of 24-K gold fiducial markers modified with micro-tines (70 [2.9×0.9 mm.]; 19 [2.1×0.7 mm.) into healthy submucosa 5-10 mm. from the resection margin, using custom-made coaxial needles. Marker migration was assessed for with intra-op bladder-filling cystogram and measurement of distance between markers. Set-up error and marker retention through completion of radiotherapy was confirmed by on-table portal imaging.

Results

Between 1/2007 and 7/2012, a total of 89 markers (3–5 per tumor site) were placed into 18 patients of mean age 73.6 years. Two patients elected cystectomy before starting treatment; 16/18 completed chemo-radiotherapy. All (100%) markers were visible with all on-table (portal, cone-beam CT), fluoroscopy, plain-film, and CT-scan imaging. In two patients, 1 of 4 markers placed at the tumor site fell-out (voided) during the second half of radiotherapy. All other markers (80/82, 98%) were present through the end of radio-therapy. No intraoperative (e.g. uncontrolled bleeding, collateral injury) or post-operative complications (e.g. stone formation, urinary tract infection, post-TUR hematuria >48 hours) occurred. Use of micro-tined fiducial tumor-site markers afforded a 2 to 6-fold reduction in bladder-area targeted with high-dose radiation.

Discussion

Placement of the micro-tined fiducial markers into the bladder was feasible and associated with excellent retention-rate and no complications. All markers were well-visualized during radiotherapy with all imaging modalities. Bladder fiducial markers improve targeting accuracy, and may increase treatment efficacy and reduce morbidity from collateral radiation.

Bladder cancer and schistosomiasis

Schistosoma-associated bladder cancer was believed, for several decades, to be a completely unique entity of disease, different from urothelial cancer. This was probably due to its distinct clinicopathologic and demographic features that varied from those of urothelial entity. The carcinogenesis is an extremely complex process resulting from the accumulation of many genetic and epigenetic changes leading to alterations in the cell proliferation regulation process. In bladder cancer, many of these carcinogenic cascades were not fully documented or somewhat conflicting. Inspite of the efforts performed, much is still needed to explore the presence or absence of the carcinogenic difference with a different etiology. The control of schistosomiasis in certain countries and the subsequent decrease in the intensity of infestation showed changing of features approaching that of urothelial tumors. However the schistosoma-associated bladder cancer presented in more advanced stages than schistosoma-non associated urothelial cancer. More recently, data are gathered that, upon applying the same treatment protocol and management care, stage by stage comparison of the treatment end-results were found to be similar in bladder cancer patients with a different etiology. All treatment options; including radical cystectomy with or without adjuvant or neoadjuvant chemo- or radiotherapy or trimodality bladder preserving treatment seem to lead to similar end-results regardless of etiologic factor(s) implicated in bladder cancer development.

Joint genitourinary cancer symposium between Egyptian and American centers

A joint symposium between Mansoura and Cleveland Universities, and the University of California, San Francisco (CA, USA) was held by the Egyptian Cancer Society in Mansoura, Egypt. The Symposium extensively discussed two topics: prostate and bladder cancer. The experiences of American and Egyptian scientists were shared in a trial to increase understanding, improve management, increase treatment outcome and decrease morbidity. Comparisons between treatment policies, management techniques and survival end results in Egypt and the USA, as well as internationally, were performed in both bladder and prostate cancer in order to determine the best policies for their management.