urografin-76 and Prostatic-Neoplasms

To determine the proportion of patients undertreated if the inferior border of the prostate field is set at the bottom of the ischial tuberosities, we reviewed the ports of 80 patients with prostate cancer who had retrograde urethrography as part of simulation for radiation therapy. For the 75 evaluable urethrograms, the mean distance from the top of the urethrogram cone to the bottom of ischial tuberosities was 1.38 cm (range, -0.48-2.90 cm). A comparison of the inferior border defined by the bottom of the ischial tuberosities and retrograde urethrography showed that 47 of 75 (62.7%) patients would have been undertreated if a margin of 1.5 cm was employed, and the prostatic apex was thought to be directly above the urethrogram cone. If the apex was thought to be 1 cm above the cone, six of 75 (8.0%) patients would have been undertreated, using a margin of 1.5 cm. Although previously published reports have established that using the bottom of the ischial tuberosities as the inferior border of the prostate field results in 10-45% undertreatment, our findings, when adjusted for the variability of prostatic apex location and margin of normal tissue employed, indicate that only 8% may actually be undertreated.

Topics: Aged; Aged, 80 and over; Barium Sulfate; Contrast Media; Diatrizoate; Diatrizoate Meglumine; Drug Combinations; Humans; Ischium; Male; Middle Aged; Patient Care Planning; Prostate; Prostatectomy; Prostatic Neoplasms; Radiotherapy Dosage; Rectum; Retrospective Studies; Supine Position; Urethra; Urography

We analyzed our urethrography procedure regarding the validity of using the ischial tuberosity line (ITL) as the caudal margin of treatment portals for prostate carcinoma. The distances of the external urethral sphincter and the lowest margin of the opacified urinary bladder were analyzed in one hundred fifteen consecutive urethrograms. None showed the urethral sphincter to be caudal to the ITL. Ten percent of the sphincters were located less than 1.0 cm cephalad to the ITL, yielding inadequate treatment coverage if the ITL was relied on. Arbitrarily considering 2.0 cm or more of the urethral irradiation to be excessive, the use of the ITL would then have resulted in unnecessary normal tissue irradiation of 42.5%. The ITL should not be used as the caudal margin for prostate treatment portals. Variation in sphincter position, as also seen on lateral projections, reveal a need for urethrography as a necessary supplement to computed tomography to plan radiation portals for prostate cancer.

Topics: Contrast Media; Diatrizoate; Diatrizoate Meglumine; Drug Combinations; Humans; Ischium; Male; Prostatic Neoplasms; Radiation Injuries; Radiography; Radiotherapy Dosage; Urethra; Urinary Bladder

Twenty cases of malignancies of the bladder and prostate were evaluated by computed tomography. This study was performed in a community hospital adjacent to a large retirement community in Southern California. Although the series was small, the results indicate that, for example, staging of carcinoma of the bladder malignancy beyond Jewitt-Marshall A can be accomplished with some ease using this modality. The extensive malignancies are easily demonstrated and their extents, in relationship to surrounding pelvic structures, are seen with considerable clarity. The use in radiation treatment planning is obvious.

Topics: Aged; Aged, 80 and over; Contrast Media; Diatrizoate; Diatrizoate Meglumine; Drug Combinations; Female; Humans; Male; Middle Aged; Neoplasm Staging; Prostatic Neoplasms; Radiotherapy Planning, Computer-Assisted; Tomography, X-Ray Computed; Urinary Bladder Neoplasms