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John Gore

Publications and source records attributed to John Gore.

5 recordsLinked to original sources
PubMed2006

The effect of postprostatectomy external beam radiotherapy on quality of life: results from the Cancer of the Prostate Strategic Urologic Research Endeavor.

BACKGROUND: Postprostatectomy salvage radiotherapy may improve prostate-specific antigen (PSA) progression-free survival, but little is known about its effect on quality of life. METHODS: From the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) data base, 1289 patients who had undergone radical prostatectomy (RP) without neoadjuvant or adjuvant hormone therapy completed validated health-related quality of life (HRQOL) questionnaires. Of these, 69 patients also received salvage radiotherapy at a median of 14 months after RP. The University of California-Los Angeles Prostate Cancer Index and the 36-item short form SF-36 questionnaire were used to compare HRQOL 12 to 18 months after external beam radiotherapy or 26 to 32 months after RP alone. Those responses also were compared with HRQOL responses from 55 men with data prior to and 12 to 18 months after primary radiotherapy. Multivariate regression identified differences between treatment groups. RESULTS: Men who underwent salvage radiotherapy were younger (P = .03) and had lower incomes (P = .01) than men who underwent RP alone; they also were younger than men who underwent primary radiotherapy (P < .01). In addition, men who received salvage radiotherapy were more likely than men who underwent RP alone to have clinically high-risk prostate cancer (P < .01). Multivariate analyses revealed that men who received salvage radiotherapy experienced more marked decrements in sexual function (P = .01) and bowel function (P = .03) than men who underwent RP alone. Salvage radiotherapy led to less impairment of sexual function (P < .01) and less sexual bother (P = .04) than primary radiotherapy. CONCLUSIONS: Although salvage radiotherapy is associated with unclear survival benefits, it adversely affects sexual and bowel function. Until randomized clinical trials demonstrate disease-specific survival benefits for salvage radiotherapy, the HRQOL detriments of additional therapy must be weighed against improved PSA progression-free survival.

Aged↗
PubMed2006

Perineocele: symptom complex, description of anatomic defect, and surgical technique for repair.

OBJECTIVES: To describe the patient characteristics, physical examination and magnetic resonance imaging findings, and method of surgical repair of perineocele. A perineocele is a rare condition of an isolated central defect and herniation of the posterior perineum in patients without diffuse vaginal prolapse. METHODS: The evaluation consisted of history and physical examination and magnetic resonance imaging. With the patient in the dorsal lithotomy position, an inverted Y incision was made from the posterior vagina to the posterior rectum. The transverse perineal musculature, superficial perineal membrane, and external anal sphincter were approximated. The perineal distance from the posterior fourchette to the anus was measured preoperatively and postoperatively. Symptom and anatomic assessments were done at each postoperative visit. RESULTS: A total of 6 patients were treated, with a mean follow-up of 9.5 months. The symptoms at presentation consisted of perineal pressure, severe constipation, and the need for manual perineal reduction for defecation. The physical findings included a lack of vaginal prolapse, convexity of the perineum, and an increase in the distance from the posterior fourchette to the rectum. Dynamic magnetic resonance imaging showed no anomaly of the vaginal wall. Preoperatively, the average perineal distance was 11.2 cm and postoperatively it was 4 cm. The perineocele was successfully repaired in all patients. All but 1 patient had significant relief of constipation. CONCLUSIONS: Posterior levator defects can result in perineal hernia with perineal body attenuation, separation of the transverse perineal and anal sphincter musculature, and development of a perineocele. The relief of symptoms and correction of the anatomic defect can be achieved by reapproximation of these structures.

Aged↗
PubMed2004

Optimizing Compton camera geometries.

Compton cameras promise to improve the characteristics of nuclear medicine imaging, wherein mechanical collimation is replaced with electronic collimation. This leads to huge gains in sensitivity and, consequently, a reduction in the radiation dosage that needs to be administered to the patient. Design modifications that improve the sensitivity invariably compromise resolution. The scope of the current project was to determine an optimal design and configuration of a Compton camera that strikes a balance between these two properties. Transport of the photon flux from the source to the detectors was simulated with the camera geometry serving as the parameter to be optimized. Two variations of the Boltzmann photon transport equation, with and without photon polarization, were employed to model the flux. Doppler broadening of the energy spectra was also included. The simulation was done in a Monte Carlo framework using GEANT4. Two clinically relevant energies, 140 keV and 511 keV, corresponding to 99mTc and 18F were simulated. The gain in the sensitivity for the Compton camera over the conventional camera was 100 fold. Neither Doppler broadening nor polarization had any significant effect on the sensitivity of the camera. However, the spatial resolution of the camera was affected by these processes. Doppler broadening had a deleterious effect on the spatial resolution, but polarization improved the resolution when accounted for in the reconstruction algorithm.

Air↗
PubMed2003

Laparoscopic partial nephrectomy and minimally invasive nephron-sparing surgery.

Surgical extirpation remains the most effective therapy for renal cell carcinoma. The surgical management of renal masses has evolved away from radical nephrectomy and now includes nephron-sparing surgery for small tumors. Nephron-sparing surgery has similar cure rates and does not appear to compromise cancer control. As the detection of small renal masses by widespread abdominal imaging continues to increase, so will the demand for minimally invasive nephron-sparing procedures. Despite progress in surgical techniques, laparoscopic partial nephrectomy remains a technically challenging procedure. In this review, we discuss the challenges and recent advances in laparoscopic partial nephrectomy and other minimally invasive approaches to renal masses.

Carcinoma, Renal Cell↗