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S J Buskirk

Publications and source records attributed to S J Buskirk.

At least 19 recordsLinked to original sources
PubMed2001

Lymph node-positive prostate cancer: evaluation of the results of the combination of androgen deprivation therapy and radiation therapy.

OBJECTIVE: To evaluate the outcome of patients with pathologic stage IV prostate cancer treated with androgen ablation plus external-beam radiation therapy. PATIENTS AND METHODS: Sixty consecutive patients treated between August 1986 and February 1995 with androgen ablation plus radiation therapy for stage IV (T1-4 N1 M0) adenocarcinoma of the prostate were selected for outcome analysis in this retrospective study. Bilateral pelvic lymphadenectomy was performed in 56 patients (93%). The 4 remaining patients had pelvic adenopathy on computed tomography, which was confirmed histologically in all patients. The median pretreatment prostate-specific antigen (PSA) level was 28.8 ng/mL (mean, 55 ng/ mL; range, 0.1-428 ng/mL). All patients received radiation therapy to the prostate, and 29 (48%) had pelvic node radiation. Biochemical failure was defined according to the American Society for Therapeutic Radiology and Oncology criteria of 3 successive increases in the PSA level. RESULTS: The median follow-up duration for surviving patients was 101.1 months (range, 20-134 months). Biochemical failure with (in 2 patients) or without (in 10 patients) clinically evident disease relapse was noted in 12 patients (20%). Four additional patients (7%) had clinical relapse without biochemical failure. Local recurrences were observed in 6 patients (10%), and this clinical impression was confirmed by biopsy in 4 patients. Thirteen patients (22%) died of causes related to prostate cancer. The biochemical relapse-free, clinical disease-free, overall, and cause-specific survival rates at 5 years were 82%, 84%, 76%, and 80%, respectively. CONCLUSIONS: This observational case series of patients treated with the combination of external-beam radiation therapy and permanent androgen ablation for pathologic stage IV prostate cancer suggests that the addition of androgen deprivation therapy to radiation therapy may improve disease outcome. In the absence of randomized trial results, these observations may be beneficial in clinical decision making.

Adenocarcinoma↗
PubMed2000

Radiotherapy for isolated serum prostate specific antigen elevation after prostatectomy for prostate cancer.

PURPOSE: Elevated serum prostate specific antigen (PSA) may be the initial and only indication of disease recurrence after prostatectomy for prostate cancer. External beam radiotherapy may be given in this setting in an attempt to eradicate the disease but therapeutic outcomes after this approach require further description. We describe the intermediate term outcome in a large group of patients treated with radiotherapy and identify pre-therapy factors associated with disease outcome. MATERIALS AND METHODS: We retrospectively studied a cohort of 166 consecutive patients treated with radiotherapy between July 1987 and May 1996. The Kaplan-Meier method was used to describe patient outcome for the overall study group, and statistical associations of pre-therapy variables with outcome were sought to identify predictive factors. RESULTS: At a median followup of 52 months 46% (95% confidence interval 38 to 55) of patients were expected to be free of biochemical relapse 5 years after radiotherapy. Multivariate analysis identified pathological classification (seminal vesicle invasion), tumor grade and preradiotherapy serum PSA as independent factors associated with biochemical relapse. Although in 1 of 6 patients a chronic complication was attributed to radiotherapy, it was often mild and self-limited in nature. CONCLUSIONS: In our current series approximately half of the patients treated with radiotherapy for an isolated elevation of serum PSA after prostatectomy were free of biochemical relapse at 5 years of followup. Radiotherapy may be given in this setting with modest long-term morbidity.

Adult↗
PubMed1997

External radiation therapy and transcatheter iridium in the treatment of extrahepatic bile duct carcinoma.

PURPOSE/OBJECTIVE: Review survival, prognostic factors, and patterns of failure in patients with extrahepatic bile duct (EHBD) carcinoma treated with external beam irradiation (EBRT) and transcatheter iridium. METHODS AND MATERIALS: The charts of 24 patients with EHBD cancer treated with EBRT and transcatheter boost were reviewed. All patients had transhepatic biliary tubes or endoprostheses placed. Two patients underwent hemihepatectomy with hepaticojejunostomy formation but had residual disease. Two patients had biopsy proven adenopathy. Five patients had Grade 1 adenocarcinoma, nine Grade 2, six Grade 3, and one Grade 4 disease. Median EBRT dose was 50.4 Gy delivered in 1.8 Gy/day fractions. Median transcatheter boost at 1 cm radius was 20 Gy. Nine patients received concomitant 5-Fluorouracil (5-FU) during EBRT. RESULTS: Median survival was 12.8 months (range 7.5 months to 9 years). Overall 2- and 5-year survival rates were 18.8 and 14.1%, respectively (three disease-free survivors > or =5 years). One patient is still alive without relapse 10 years from diagnosis and 5 years after liver transplantation for liver failure (no cancer in specimen, underlying sclerosing cholangitis). Two additional long-term survivors had no evidence of relapse 6.9 and 8.2 years after diagnosis. Histologic grade, lymph node status, cystic, hepatic, common hepatic or common bile duct involvement, surgical resection, radiation therapy dose, and chemotherapy did not significantly effect survival due to the number of patients analyzed. There was a trend towards improved survival with the addition of 5-FU chemotherapy (5-year survival in two of nine patients, or 22%). Eight of 24 patients (33%) demonstrated radiographic evidence of local recurrence. Distant metastases developed in 6 of 24 (25%) patients. The most common complications were tube related cholangitis (50%) and gastric/duodenal ulceration or bleeding (42%). CONCLUSION: External beam irradiation combined with a transcatheter boost can result in long-term survival of patients with EHBD cancer. Both distant metastases and local recurrence develop in 25-30% of patients despite irradiation. Survival may be improved by using chemotherapy in combination with EBRT to impact disease relapse (local and distant). Because there may be a dose response with irradiation, survival may also be improved by increasing the dose of radiation delivered by transcatheter boost. A Phase II trial is being developed using a combination of 45-50 Gy EBRT with concomitant 5-FU delivered by protracted venous infusion followed by a 25-30 Gy transcatheter boost.

Adult↗
PubMed1997

Has radiotherapy become too expensive to be considered a treatment option for early glottic cancer?

BACKGROUND: External beam radiotherapy and surgery produce equivalent long-term survival and tumor control in early glottic cancer. The expense and cost of radiotherapy have been challenged. METHODS: A retrospective review was performed for 57 patients undergoing radiotherapy for glottic cancer. End points included local tumor control, relapse-free survival, cause-specific survival, medical charges, and costs. The results were compared with those of 265 patients who underwent transoral endoscopic removal or an open laryngeal procedure at the same institution. RESULTS: The local control, larynx preservation, re-treatment, voice quality, relapse-free survival, and cancer death results and medical charges and costs are reported by treatment. CONCLUSIONS: Radiotherapy provides at least equivalent, if not superior, local tumor control, larynx preservation, voice quality, and survival, compared with the surgical options. Overall medical charges and costs for radiotherapy are similar to transoral endoscopic resection and less than partial vertical laryngectomy.

Adult↗
PubMed1997

Placebo-controlled trial of sucralfate for inhibiting radiation-induced esophagitis.

PURPOSE: To determine whether a sucralfate oral solution can prevent/alleviate radiation-induced esophagitis. PATIENTS AND METHODS: Patients included on this clinical trial were beginning thoracic radiation therapy to the mediastinum. Following stratification, they were randomized, in a double-blind manner, to receive a sucralfate solution or an identical-appearing placebo solution. Esophagitis was measured by physicians who used standard criteria and also by patients who used short questionnaires completed weekly during the course of the trial. RESULTS: A total of 97 assessable patients were entered onto this clinical trial. During the first 2 weeks of the study, two placebo patients (4%) stopped their study medication, compared with 20 sucralfate patients (40%). This was related to substantially increased incidences of gastrointestinal toxicity (58% of sucralfate patients v 14% of placebo patients; P > .0001). There was no substantial benefit from the sucralfate in terms of esophagitis scores. CONCLUSION: This oral sucralfate solution does not appear to inhibit radiation-induced esophagitis and is associated with disagreeable gastrointestinal side effects in this patient population.

Administration, Oral↗
PubMed1996

Radiation therapy for glottic cancer using 6-MV photons.

BACKGROUND: It has been recommended that cobalt-60 or 4-MV photons be used when treating glottic cancer with radiation therapy. Underdosing may occur when using higher energy photons, particularly when the anterior commissure is involved. The authors report their experience using higher energy photons (6 MV) for the treatment of glottic cancer. METHODS: Between January 1975 and July 1991, 73 patients with Tis, T1, T2, or T3 glottic tumors underwent radiation therapy with curative intent. Cobalt-60 or 4-MV photons were used to treat the cancers of 30 patients, and 6-MV photons were used to treat 43 patients. Clinical records were reviewed retrospectively to determine patterns of treatment failure, cancer deaths, and local tumor control in the 43 patients receiving treatment with 6-MV photons. Patients were followed until death or for a minimum of two years. RESULTS: Treatment failures were: local recurrence, one patient; local recurrence and distant metastasis, one patient; delayed neck metastasis, two patients; and delayed neck metastasis with distant metastasis, one patient. Three patients who had treatment failure are alive and free of cancer after salvage treatment. Two patients died of neck and distant metastases. The 2-year initial local tumor control rate was 94.8%. CONCLUSIONS: Glottic cancer can be treated successfully with 6-MV photons. Local tumor control is similar to that reported using cobalt-60 or 4-MV photons.

Adult↗
PubMed1996

Evaluation of serum prostate-specific antigen levels after postoperative radiation therapy for pathologic stage T3, N0 prostate cancer.

OBJECTIVE: To analyze freedom from progression of serum prostate-specific antigen (PSA) levels in patients who have received radiation therapy after radical prostatectomy for pathologic stage T3, N0 prostate cancer. DESIGN: We assessed the freedom from PSA progression after postoperative radiation therapy and its relationship to several potential prognostic factors during a median follow- up of 43 months. MATERIAL AND METHODS: Thirty Mayo patients received postoperative radiation therapy for pathologic stage T3, N0 prostate cancer between January 1988 and April 1993. Radiation therapy was initiated within 6 months after prostatectomy. Radiation doses ranged from 60 to 67 Gy. RESULTS: "Freedom from PSA failure" was defined as the actuarial risk of maintaining a serum PSA level at 0.3 ng/mL or less. The freedom from failure rate was 66% at 3 and 4 years. Prognostic factors significantly associated with an improved freedom from failure were a pre-radiation PSA level of 1.0 ng/mL or less and no seminal vesicle involvement. A trend toward an improved freedom from failure was noted in patients with low-grade (1 and 2) tumors in comparison with high-grade (3 and 4) tumors. Treatment-related morbidity was minimal. CONCLUSION: Radiation therapy after radical prostatectomy for pathologic stage T3, N0 prostate cancer seems to provide an improved freedom from PSA failure in comparison with that noted in other series of similar patients treated with radical prostatectomy only.

Aged↗
PubMed1996

The use of radiotherapy for patients with isolated elevation of serum prostate specific antigen following radical prostatectomy.

PURPOSE: An analysis was performed to assess the outcome of patients who received radiotherapy for isolated elevation of serum prostate specific antigen (PSA) levels following radical retropubic prostatectomy. MATERIALS AND METHODS: Forty-six patients were initially treated for localized prostate cancer with radical retropubic prostatectomy following negative pelvic lymphadenectomy. These patients had detectable serum PSA 6 or more months postoperatively. No patient had other clinical evidence of recurrent disease as determined by history, physical examination, bone scan, computerized tomography of the abdomen and pelvis, chest radiographs, complete blood cell counts and serum chemistry profiles. The patients received prostate bed irradiation using 10 MV. x-rays and a 4-field approach. Doses ranged from 60.0 to 67.0 Gy. in 1.8 to 2.0 Gy. fractions. Freedom from failure after radiotherapy was defined as maintaining a PSA of 0.3 ng./ml. or less without hormonal intervention. RESULTS: In 27 of the 46 patients (59%) PSA had decreased to 0.3 ng./ml. or less at last measurement without hormonal intervention. The freedom from failure rate was 50% at 3 and 5 years. More favorable responses to salvage radiotherapy occurred in patients with low grade tumors and serum PSA 1.1 ng./ml. or less at initiation of radiotherapy. Patients, receiving radiation doses of 64 Gy. or more had more favorable response rates than those receiving lesser doses. CONCLUSIONS: Isolated elevations of serum PSA following prostatectomy reflect residual disease. Radiotherapy administered to the prostate bed effectively decreased serum PSA in approximately half of the cases. This effect appears to be accomplished by eradicating tumor cells in the prostate bed.

Combined Modality Therapy↗
PubMed1994

Tonsil cancer. Patterns of failure after surgery alone and surgery combined with postoperative radiation therapy.

BACKGROUND: The authors determined the patterns of treatment failure in patients treated with surgery alone or surgery combined with postoperative radiation therapy for squamous cell carcinoma of the tonsil. METHODS: Seventy-two patients underwent surgery alone (56) or surgery and postoperative adjuvant radiation therapy (16). All patients were followed up until death (40 patients) or for a minimum of 3.5 years. For patients treated with surgery alone, clinic notes, operative notes, and pathology reports and slides were reviewed to identify clinical or pathologic predictors of recurrence above the clavicles, cause-specific survival, and overall survival. For patients undergoing postoperative adjuvant radiation therapy, demographic, treatment, and pathologic variables were analyzed to identify factors associated with control of disease above the clavicles, disease-free survival, and overall survival. RESULTS: The main pattern of treatment failure was above the clavicles. It occurred in 39% of patients treated with surgery alone and was significantly related (P = 0.002) to the overall clinical TNM stage. Disease recurrence above the clavicles occurred in 31% of patients undergoing surgery and postoperative adjuvant radiation therapy, despite their more advanced neck disease. Five-year overall survival for patients with clinical Stage III and IV disease who were treated with surgery and post-operative adjuvant radiation therapy was 100% and 78%, respectively. Five-year overall survival for patients treated with surgery alone who had clinical Stage III, IVA, or IVB disease was 56%, 43%, and 50%, respectively. CONCLUSION: We recommend postoperative adjuvant radiation therapy for patients with clinical Stage III or IV squamous cell carcinoma of the tonsil who have undergone complete surgical resection because this appears to improve control of disease above the clavicles and overall survival.

Adult↗
PubMed1994

Primary head and neck cancer. Histopathologic predictors of recurrence after neck dissection in patients with lymph node involvement.

OBJECTIVE: Retrospectively analyze several histopathologic variables that may predict neck recurrence after neck dissection. DESIGN: From 1970 through 1980, 284 patients with pathologically confirmed metastatic squamous cell carcinoma underwent neck dissection and received no adjuvant therapy. Kaplan-Meier evaluation estimated a 74% 2-year neck recurrence-free rate. After adjusting for the standard covariates of age, gender, neck stage, and tumor grade, we also controlled for the time-dependent covariates of primary recurrence, occurrence in the side of the neck not operated on, or development of new head and neck primary disease. SETTING: A large referral-based practice. RESULTS: The number of lymph nodes involved, invasion of vascular/lymphatic space, invasion of soft tissue, and desmoplastic lymph node pattern adversely affect neck recurrence. A desmoplastic stromal pattern was associated with almost a sevenfold increased risk of neck recurrence. To our knowledge, this finding has not been reported previously. CONCLUSION: Histopathologic evaluation of metastatically involved cervical nodes can identify patients with head and neck cancer who are at high risk for recurrence.

Adult↗
PubMed1994

Radiotherapy for isolated increases in serum prostate-specific antigen levels after radical prostatectomy.

OBJECTIVE: To assess the outcome of radiotherapy in patients with increased serum prostate-specific antigen (PSA) levels 6 months or more after radical prostatectomy. DESIGN: In 27 Mayo Clinic patients, we examined the results of radiotherapy relative to various potentially prognostic factors during a median follow-up of 25 months. MATERIAL AND METHODS: All 27 patients had no nodal involvement at the time of prostatectomy and no clinical evidence of disease, as determined by history, physical examination, a radionuclide bone scan, computed tomography of the abdomen and pelvis, chest roentgenography, complete blood cell counts, and serum chemistry profiles. With use of 10-MV photons and a four-field approach, these patients received irradiation to the prostatic bed (60 to 67 Gy in 1.8- to 2.0-Gy fractions). RESULTS: Levels of PSA initially decreased in 24 of the 27 patients (89%). In 16 of the 27 patients (59%), the PSA level decreased to 0.3 ng/mL or less without hormonal intervention. "Freedom from failure" (defined as the actuarial chance of maintaining a PSA level of 0.3 ng/mL or less) was 58% at 2 years and 48% at 3 years. The response to salvage radiotherapy was more favorable in patients with no tumor spread into the seminal vesicles and those with serum PSA levels of less than 1.1 ng/mL at the beginning of radiotherapy than in those with seminal vesicle involvement or higher PSA levels. In addition, patients who received radiation doses of 64 Gy or more had more favorable responses than did those who received lesser doses. Radiotherapy resulted in no severe toxicity. No patient had clinical evidence of disease at the time of this report. CONCLUSION: Isolated increases in serum PSA after prostatectomy indicate the presence of residual or recurrent disease, and radiotherapy effectively decreases the PSA in approximately half the cases. This result is achieved by eradicating residual or recurrent cancer in the postoperative tumor bed.

Aged↗
PubMed1994

Radiation therapy for squamous cell carcinoma of the tonsil.

OBJECTIVE: To characterize the patient population referred for radiation therapy for tonsillar cancer and to assess the effectiveness of use of only radiation therapy in this population. DESIGN: We retrospectively reviewed the medical records of 21 patients referred to the Mayo Clinic in Rochester, Minnesota, from 1970 through 1988 for radiation therapy for squamous cell carcinoma of the tonsillar region. MATERIAL AND METHODS: The median age of the 21 study patients was 65 years (range, 45 to 92), and the male:female ratio was 12:9. In all patients, follow-up continued until death or for 2.25 to 16.25 years. Of the 21 patients, 17 had tumors that were either surgically unresectable or medically inoperable, and 20 had clinical stage III or IV disease. The median total dose of irradiation was 55 Gy. RESULTS: Local control of the tonsillar cancer was as follows: T2, four of five patients; T3, seven of seven; and T4, five of nine. Thus, the local control rate was 76%. No associations were discovered among local control, total dose of radiation therapy, dose per fraction, overall duration of treatment, age, sex, or reason for referral for radiation therapy. Control of metastatic cervical adenopathy was as follows: clinical stage N1, seven of seven patients; N2, six of seven; and N3, one of one. (Six study patients had no nodal involvement.) The estimated 5-year cause-specific survival and overall survival rates were 77% and 31%, respectively. CONCLUSION: This study substantiates the effectiveness of radiation therapy in patients with squamous cell carcinoma of the tonsil.

Actuarial Analysis↗
PubMed1993

Pineal parenchymal tumors. Clinical, pathologic, and therapeutic aspects.

BACKGROUND: Pineal parenchymal tumors are rare; therefore, only limited clinical data regarding their behavior is available. This study was performed to provide further information regarding the pathologic features, clinical behavior, and response to therapy of these tumors. METHODS: This study includes data concerning 30 patients (15 male and 15 female patients) with pineal parenchymal tumors (PPT) diagnosed between 1939 and 1991. Based on gross and microscopic features, tumors were divided into four groups: pineocytomas (9); PPT with intermediate differentiation (4); mixed PPT exhibiting elements of both pineocytoma and pineoblastoma (2); and pineoblastomas (15). At the time of diagnosis, four patients had evidence of spinal seeding (two with pineoblastoma, two with PPT with intermediate differentiation). Twenty-two patients received radiation therapy (RT): 6 were treated to local fields, 7 to the whole brain, and 9 to the craniospinal axis. RESULTS: For patients who received RT and had a minimum follow-up of 6 months, local failure occurred in one of four patients with pineocytomas, zero of four patients with PPT with intermediate differentiation, one of two with mixed PPT, and four of nine (44%) with pineoblastomas. In patients receiving > or = 50 Gy to the primary tumor, 0 of 12 had local failure compared with 6 of 7 (86%) patients receiving lesser doses. Leptomeningeal failure occurred in zero of four patients with pineocytomas, zero of four patients with PPT with intermediate differentiation, one of two with mixed PPT, and four of nine with pineoblastomas. All leptomeningeal failures occurred in patients with persistent primary tumor. Of the patients with seeding tumors (PPT other than pineocytomas) one of seven (14%) developed leptomeningeal failure when treated with craniospinal irradiation, compared with four of eight (50%) treated to lesser volumes. The projected 1-year, 3-year, and 5-year survival rates of patients with pineocytomas were 100%, 100%, and 67%, and were 88%, 78%, and 58% for those with the other forms of PPT, respectively. CONCLUSIONS: RT recommendations are described in detail and include the use of doses of > or = 50 Gy to areas of gross disease and the administration of craniospinal irradiation in patients with tumors prone to seeding. Surgical, chemotherapeutic, and pathologic considerations are discussed.

Adolescent↗
PubMed1993

Postoperative irradiation for tonsillar carcinoma.

From January 1975 through July 1987 at the Mayo Clinic, 16 patients received postoperative adjuvant radiation therapy for squamous cell carcinoma of the tonsil (pathologic stage I in 4 patients, stage III in 3, and stage IV in 9). Follow-up was continued for a minimum of 2 years or until death. At 5 years, overall survival was 74% and disease-free survival was 68% for the entire group of patients. The local-regional control rate at 5 years was 83% for 12 patients with pathologic stage III or IV disease; the 5-year disease-free survival rate was 74%. The results with use of postoperative irradiation for stage III or IV tonsillar cancer seem superior to those for a similar historical group of patients who underwent surgical treatment only. Because the number of patients was small and the analysis was retrospective, our study may have included some undetected bias.

Aged↗
PubMed1992

The results of radiotherapy for isolated elevation of serum PSA levels following radical prostatectomy.

Eleven patients were initially treated for localized prostate cancer with radical retropubic prostatectomy following negative pelvic lymph node dissection. Six or more months after surgery, these patients had elevated serum prostate specific antigen (PSA) levels. No patient had other clinical evidence of disease as determined by history, physical examination, bone scan, computed tomographic scan of the abdomen and pelvis, chest radiograph, complete blood cell count, and serum chemistry profile. These patients received prostate bed irradiation using 10-MV photons and a four-field technique. Doses ranged from 60.0 to 65.8 Gy in 1.8 to 2.0 Gy fractions. Levels of serum PSA were monitored and decreased initially in all treated patients. In two patients, levels of PSA increased after this initial decrease. In 7 of the 11 patients (64%), PSA levels decreased to less than or equal to 0.3 ng/mL at last measurement. Radiotherapy resulted in no severe toxicity. None of the patients had developed clinical evidence of disease at the time of this report. Isolated elevations of serum PSA after prostatectomy reflect residual disease, and radiotherapy appears to effectively decrease the PSA levels in most cases. This effect appears to be accomplished by killing locally residual or recurrent cancer in the postoperative tumor bed.

Aged↗
PubMed1992

Radiotherapy treatment planning for prostate cancer in patients with prosthetic hips.

Patients diagnosed with prostate cancer may also have a prosthetic hip. When planning radiotherapy for these patients, one must consider the attenuation of the dose when the beam passes through the prosthetic hip. It is best to avoid administration of radiation to the target through the prosthesis. Example treatment plans are evaluated. The potential advantages and disadvantages of each plan are reviewed.

Hip Prosthesis↗
PubMed1992

Results of radiotherapy for chemodectomas.

Between 1974 and 1988, 10 Mayo Clinic patients had unresectable, locally recurrent, or partially resected chemodectomas. Of these 10 tumors, 9 were confirmed pathologically, and 1 was diagnosed clinically. The chemodectoma was located in the jugular bulb in five patients, the middle ear in three, and the carotid body in two. The following symptoms were noted: tinnitus (in eight patients), loss of hearing (in six), hoarseness (in six), dysphagia (in four), pain (in three), and alteration of mental status (in one). Many patients had more than one symptom. Treatment was delivered with megavoltage photons and electrons; total doses ranged from 16.2 to 52 Gy (median, 46 Gy), and the daily doses ranged from 1.6 to 2.4 Gy. Follow-up among the nine survivors ranged from 3 1/2 to 16 years (median, 7 1/2 years). In one patient, the response could not be assessed because the patient died of renal failure 4 months after treatment. All nine assessable patients had decreased symptoms and objective control of the tumor (no evidence of progression of disease). Of the nine assessable patients, four had complete responses, one had a partial response, and four had stable disease. No patient experienced progression of disease after radiotherapy. We conclude that radiotherapy for chemodectomas yields successful results--namely, decreased symptoms and objective control of the tumor.

Adult↗