title: Intravesical lipiodol injection technique for image-guided radiation therapy for bladder cancer.
abstract: BACKGROUND
  To describe the technique of injecting Lipiodol in the submucosa of the urinary bladder wall as a novel modality to improve localization of muscle-invasive bladder tumors before image-guided radiation therapy.
  
  
  METHODS
  Eight patients underwent submucosal Lipiodol injections at transurethral bladder tumor reresection. A rigid cystoscope with a working port was used to inject Lipiodol into bladder submucosa circumferentially around the tumor bed (2-3 mm from margin of resection). Approximately 20-30 injections were used to demarcate the tumor bed for external beam radiation therapy, which was used as part of a bladder-sparing approach. All patients were diagnosed with clinically localized, high-grade, muscle-invasive carcinoma and were deemed nonsurgical candidates or were unwilling to undergo radical cystectomy. Five of the 8 patients received radiation at our institution. Lipiodol injections (95%) were visible on treatment planning computed tomographic scans and kilovoltage portal images throughout the 7-week course of image-guided radiation therapy. In 2 of 5 patients, the tumor bed based on Lipiodol extended outside a planning target volume that would have been treated with radiation therapy based on cystoscopy reports and computed tomographic scans without Lipiodol. There were no adverse events or treatment-related toxicities secondary to Lipiodol injection.
  
  
  CONCLUSIONS
  Intravesical Lipiodol injection is an easy-to-perform technique that is safe and effective. Lipiodol serves as a fiducial marker that improves tumor bed localization for radiation therapy, thereby reducing the likelihood of missing the tumor.
authors.affiliation: Department of Genitourinary Oncology, Moffitt Cancer Center, Tampa, FL.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Baumgarten
authors.affiliation: Department of Genitourinary Oncology, Moffitt Cancer Center, Tampa, FL.
authors.forename: Justin B
authors.initials: JB
authors.lastname: Emtage
authors.affiliation: Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Wilder
authors.affiliation: Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Biagioli
authors.affiliation: Department of Genitourinary Oncology, Moffitt Cancer Center, Tampa, FL.
authors.forename: Shilpa
authors.initials: S
authors.lastname: Gupta
authors.affiliation: Department of Genitourinary Oncology, Moffitt Cancer Center, Tampa, FL. Electronic address: philippe.spiess@moffitt.org.
authors.forename: Philippe E
authors.initials: PE
authors.lastname: Spiess
mesh_terms: D000283:Administration, Intravesical; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage*; D015653:Cystectomy; D003558:Cystoscopy; D018572:Disease-Free Survival; D004998:Ethiodized Oil / Q000008:administration & dosage*; D006801:Humans; D008875:Middle Aged; D009092:Mucous Membrane / Q000473:pathology; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D001743:Urinary Bladder / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000532:radiotherapy*; D013520:Urologic Surgical Procedures
chemical_list: D003287:Contrast Media; D004998:Ethiodized Oil