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S J Buskirk

Publications and source records attributed to S J Buskirk.

34 records · Page 2Linked to original sources
PubMed1992

Early-stage squamous cell carcinoma of the glottic larynx managed with radiation therapy.

Between January 1975 and December 1985, 45 patients with carcinoma in situ or invasive squamous cell carcinoma of the glottic larynx received radiation therapy at the Mayo Clinic. Local control in the entire group of 45 patients was 84% (in 6 of 6 with carcinoma in situ and in 32 of 39 with invasive cancers). Three of seven patients (43%) with local recurrences underwent successful larynx-preserving surgical procedures; thus, the rate of laryngeal preservation was 91%. In our study of several treatment factors, including the duration of treatment, type of treatment (continuous course versus split course), photon energy (60Co versus 4-MV photons versus 6-MV photons), total dose, and dose per fraction, we found that only total dose of 6,300 cGy or more was associated with significantly improved local control (in 35 of 38 patients [92%]). Two patients (4%) died of uncontrolled delayed nodal metastases, one of which was preceded by a local recurrence. Severe laryngeal edema developed in two patients, associated with recurrent glottic carcinoma in one of them. No larynx was lost because of complications. In our current treatment recommendations, patients receive a total dose of 6,300 cGy in 28 fractions of 225 cGy each, administered in a continuous course with use of 6-MV photons.

Adult↗
PubMed1992

Locally recurrent non-small-cell lung cancer after complete surgical resection.

Between Jan. 1, 1976, and Dec. 31, 1985, at our institution, 37 patients who had undergone prior complete surgical resection of non-small-cell lung cancer received definitive thoracic radiation therapy (TRT) for locally recurrent disease. Of the 37 recurrences, 33 were in the pulmonary parenchyma or the hilar, mediastinal, or supraclavicular lymph nodes; the other 4 were in the chest wall. The initial stage of disease was I in 43%, II in 35%, and IIIA in 19%, whereas at the time of local recurrence, the stage was I in 8%, II in 11%, IIIA in 57%, IIIB in 22%, and IV in 3% (this patient had multiple pulmonary nodules encompassible within a single TRT field). The locally recurrent lesions were squamous cell carcinoma in 30%, adenocarcinoma or large-cell carcinoma in 46%, mixed types in 5%, and unknown type in 19%. All patients received megavoltage TRT, most often 4,000 cGy in 10 fractions administered in a split-course schedule. In addition, 15 patients received multiagent chemotherapy, usually a combination of cyclophosphamide, doxorubicin hydrochloride, and cisplatin or a regimen that included these drugs. The 2-year and 5-year survivals were 30% and 4%, respectively, and the median duration of survival was 13.7 months. Survival was not improved by the addition of chemotherapy. Approximately half of the patients had radiographic and symptomatic responses after TRT. Of 33 patients assessable for post-TRT patterns of failure, 46% had local failure only, 18% had local plus systemic failure, and 32% had systemic failure only. Two-thirds of the patients died as a direct consequence of progressive chest disease, despite receiving TRT.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Analysis of failure after curative irradiation of extrahepatic bile duct carcinoma.

Thirty-four patients with subtotally resected or unresectable carcinoma of the extrahepatic bile ducts received radiation therapy; a minimum of 45 Gy (external beam) to the tumor and regional lymph nodes +/- 5-fluorouracil (5-FU). Seventeen patients received an external beam boost of 5 to 15 Gy to the tumor, and a specialized boost was used in the remaining 17 patients (iridium-192 transcatheter seeds in 10 and intraoperative radiation therapy [IORT] with electrons in seven). The median time to death in all 34 patients was 12 months (range, 4 to 98-months). The only patients who survived longer than 18 months were those either with gross total or subtotal resection before external irradiation (2 of 6) or who received specialized boosts (192Ir, 3 of 10; IORT, 3 of 7). Local failure was documented in 9 of 17 patients who received external beam irradiation alone +/- 5-FU, 3 of 10 patients who received an 192Ir boost, and 2 of 6 patients who received an IORT boost with curative intent.

Adenoma, Bile Duct↗
PubMed1991

Radiotherapy for large symptomatic hemangiomas.

Between 1974 and 1988, 13 patients presented with large (3 to greater than 20 cm) symptomatic unresectable or partially resected hemangiomas. Tumor sites were extremities (five cases), vertebral bodies (three cases), face (two cases), pituitary fossa (one case), pelvic bones (one case), and bladder (one case). Symptoms included severe pain in eight patients, inability to use an extremity in five, vision problems in three, weakness in two, and hematuria with decreased urinary stream in one. Many patients had more than one symptom. Two of the cases were associated with life-threatening consumptive coagulopathies (Kasabach-Merritt syndrome). Therapy was delivered with both orthovoltage and megavoltage photons. Doses ranged from 6.25 to 40.0 Gy in 1.6- to 2.5-Gy fractions. Follow-up ranged from 2 to 15 years (median, 13 years). Tumor shrinkage was noted in 9 (82%) of the 11 cases in which tumor size data were collected before and after therapy. Complete response of tumor mass occurred in 4 (36%) of 11, partial response occurred in 5 (45%), and no response occurred in 2 (18%). No tumor grew after radiotherapy. Some relief in symptoms occurred in all 13 patients; 10 (77%) had complete resolution of symptoms. In both patients with life-threatening cytopenias, hematologic values returned to normal after treatment. Because the majority of the patients responded to all dose levels administered, no firm dose-response relationship was evident. However, objective (measurable) complete responses occurred in two (50%) of the four patients receiving doses of 30 Gy or greater compared with only two (29%) of the seven patients who received lesser doses. No long-term morbidity occurred. Radiotherapy of large unresectable and partially resected hemangiomas yields long-term relief of symptoms and tumor shrinkage in the majority of patients treated.

Adolescent↗
PubMed1991

Prostate cancer: retrograde urethrography to improve treatment planning for radiation therapy.

Thirty men with clinical stage A or B prostate cancer underwent retrograde urethrography at the time of simulation. The inferior edge of the prostate apex was visualized as an abrupt narrowing of the column of contrast material at the urogenital diaphragm. The distance between the line connecting the lower poles of the ischial tuberosities and the site of abrupt narrowing of the column of contrast material (prostate apex) ranged from 0.2 cm to 2.9 cm (median, 1.5 cm). In eight of the 30 (27%) cases, this distance was less than 1.0 cm. In these patients, it would have been inappropriate to place the lower field edge at the bottom of the ischial tuberosities because this would have resulted in an insufficient margin (less than 1.0 cm) below the prostate apex. The authors quantify the percentage of patients who would not be adequately treated if the ischial tuberosities were used as the lower border of the treatment fields. The information obtained at retrograde urethrography can be used to place the inferior border of the treatment fields properly, at least 1.0 cm below the prostate apex.

Humans↗
PubMed1989

Patterns of failure after total laryngectomy for glottic carcinoma.

The 136 patients who underwent total laryngectomy as the primary treatment for squamous cell carcinoma of the glottis at the Mayo Clinic in 1970 through 1981 were followed by retrospective record review for at least 4 years or until death, local recurrence, neck recurrence, or delayed neck metastasis. Cancer recurred or progressed in a previously untreated area in 35 patients; for the 29 affected above the clavicles, the median time to manifestation was 9.9 months. A Cox model with four risk factors (P less than 0.05) was found to predict failure above the clavicles: lymph node metastasis in the laryngectomy specimen (Delphian, pretracheal, tracheoesophageal, parathyroid), primary tumor more than 1.5 cm in greatest diameter, subglottic extension, and lymph node metastasis in the neck dissection specimen. A simple risk score computed from the Cox model shows that the more factors present, the higher the risk of disease progression or recurrence.

Adult↗
PubMed1989

External beam irradiation for retinoblastoma: patterns of failure and dose-response analysis.

Eighteen children with retinoblastoma (25 eyes) were treated with external beam radiation at the Mayo Clinic between January 1977 and January 1987; 15 eyes were in groups I to III and 10 were in groups IV and V (Reese-Ellsworth classification). The median number of tumors per eye was 3. Radiation therapy consisted of 4- or 6-MV photons. Doses varied from 39 to 51 Gy in 1.8- to 3.0-Gy fractions. Fourteen eyes were treated through lateral fields by anterior segment-sparing techniques, and 11 eyes were treated by an anterior approach with no attempt at anterior segment sparing. All patients survived (median follow-up, 31.5 months). Cataracts developed in five eyes at a median of 23 months, four in eyes treated with anterior segment-sparing techniques. Of the 15 group I to III eyes, 6 required additional treatment; 4 were salvaged with cryotherapy or photocoagulation and 2 were enucleated. Of the 10 group IV and V eyes, 8 required additional treatment; 4 were salvaged with cryotherapy or photocoagulation, 1 with persistent disease is being followed closely, and 3 were enucleated. Ten (71%) of the 14 eyes treated with anterior segment-sparing techniques required additional treatment (9 of the 10 for tumors anterior to the equator). Four (36%) of the 11 eyes treated with an anterior approach required additional treatment (3 of the 4 for tumors in the posterior pole of group IV or V eyes). Ninety percent of the tumors 10 disc diameters or smaller (1 disc diameter = 1.6 mm) were controlled independently of dose and fractionation used when they were not in the low-dose area of the anterior retina of an eye treated with an anterior segment-sparing technique. We find that use of lateral, anterior segment-sparing techniques has a high risk of anterior retinal tumor development and cataract formation and should be abandoned in favor of techniques that treat the entire retina. A dose of 45 Gy in 1.8-Gy fractions appears to be adequate for local control of tumors smaller than 10 disc diameters. Larger tumors may require additional treatment.

Child, Preschool↗
PubMed1988

Patterns of failure in primary testicular non-Hodgkin's lymphoma.

Patterns of failure were analyzed in 30 patients with testicular non-Hodgkin's lymphoma: 16 had stage IE disease, ten had stage IIE, and four had stage IV. After orchiectomy, two of the 16 patients with stage IE disease received no additional therapy, one received multiagent chemotherapy, and 13 received pelvic and para-aortic radiation. Twelve patients with stage IE disease had progression, and the median time to progression was 12 months. Of the 14 patients with extratesticular involvement (stage IIE or IV), one (stage IV) received no treatment after orchiectomy, three (stage IIE) received para-aortic and pelvic radiation, and ten (seven stage IIE and three stage IV) received multiagent chemotherapy with or without radiation. Eight of the patients with stage IIE or IV disease had progression, and the median time to progression was 11 months. Widespread extranodal progression was observed in 17 of the 20 patients who had progression. The tendency of testicular lymphoma for early systemic progression suggests a need for multiagent chemotherapy in initial management.

Adult↗
PubMed1987

Ovarian dysgerminoma: a retrospective analysis of results of treatment, sites of treatment failure, and radiosensitivity.

Thirty-five patients with a diagnosis of pure ovarian dysgerminoma underwent assessment at our institution between 1950 and 1984. The median age of these patients was 21 years (range, 8 to 41 years). The surgical pathologic stages of the tumors were as follows: stage IA1 in 18 patients, stage IA2 in 2, stage IB1 in 2, stage IC in 1, stage IIB in 2, stage III in 9, and stage IV in 1. The overall survival at 5, 10, and 20 years was 94.3%, 82.9%, and 82.9%, respectively, for all 35 patients and 100%, 83.9%, and 83.9%, respectively, for the 18 patients with stage IA1 lesions. The maximum interval from diagnosis to relapse was 3.7 years. All patients were under surveillance for a minimum of 2 years (median follow-up, 15.9 years). Of the 18 patients with stage IA1 disease, 16 did not receive prophylactic radiation therapy to the para-aortic lymph nodes, and in 6 of the 16 (38%) recurrent disease developed in this region. Five of these patients were salvaged with radiation therapy and one with radiation therapy and subsequent chemotherapy. No definite correlation was noted between the size or mass of the resected unilateral encapsulated tumor and the risk of development of recurrent disease. For patients with stage IA1 dysgerminoma who have undergone unilateral oophorectomy, two treatment options seem reasonable: (1) observation, with radiation therapy reserved for subsequent recurrence, or (2) prophylactic radiation therapy (2,000 cGy) to para-aortic and ipsilateral common iliac lymph nodes, which would preserve fertility.

Adolescent↗
PubMed1985

Radiotherapeutic management of primary thyroid lymphoma.

The purpose of this study was to evaluate the radiotherapeutic management of 38 patients, with malignant lymphoma of the thyroid, seen at the Mayo Clinic between 1965 and 1979. There were 8 males and 30 females with ages ranging from 34 to 90 years (mean age of 65 years). A tissue diagnosis was made in all patients and tissue was available for reclassification under the "Working Formulation" in 31 of the 38 patients. Twenty-six patients had intermediate grade histology, four low grade and one indeterminate. Twenty patients were clinical Stage IE, 14 patients Stage IIE, one patient Stage IIIE, one patient Stage IV and two patients were unstaged. All patients were treated with approximately 4000 rad megavoltage irradiation (range 2400-6000 rad) to the neck only (10 patients) or neck and mediastinum (28 patients). Twenty patients received subdiaphragmatic radiotherapy and four patients received adjuvant chemotherapy. Median follow-up was 56 months with minimum follow-up of 30 months. Overall disease-free survival at five years was 59%. Of 14 patients who experienced a recurrence, 10 (71%) failed in two or more sites. The most common site of failure was in para-aortic lymph nodes. One year survival following recurrence was 29%; however, four of six patients receiving salvage therapy survived at least two years. Patients receiving radiation treatment to the neck and mediastinum and those with no gross residual disease at the initiation of radiotherapy were less likely to develop a recurrence. Patients receiving a planned break during the course of therapy did not have reduced overall disease-free survival. However, 4 of 20 patients (20%) who received split course therapy failed within the radiation fields compared to 2 of 18 patients (11%) who had no treatment break. Only 1 of 4 patients (25%) receiving adjuvant chemotherapy survived one year. Side effects of radiotherapy were minimal. We believe the radiotherapeutic management of clinical Stage IE and IIE primary thyroid lymphoma should include treatment of the neck, axillae and mediastinum to a dose of approximately 4000 rad using a continuous course technique. Additionally, gross total removal of the disease surgically may be beneficial.

Adult↗
PubMed1984

Analysis of failure following curative irradiation of gallbladder and extrahepatic bile duct carcinoma.

Twenty patients with carcinoma of the gallbladder (GB-4 patients) or extrahepatic bile ducts (EHBD-16 patients) received radiation therapy with curative intent between January, 1980 and December, 1982. All 20 received 4500-5000 rad in 180-200 rad fractions to the tumor and regional lymph nodes. A 1000 to 1500 rad external beam boost was delivered in 180-200 rad fractions in 10 patients who received external beam alone or concomitant 5-Fluorouracil (5-FU). Three of the four GB and 5 of the 16 EHBD patients received a transcatheter boost with 192-Iridium (192Ir) to a dose of 2000-2500 rad calculated at a 0.5-0.1 cm radius. An additional 2 patients with EHBD lesions received an intraoperative electron (IORT) boost of 1500-2000 rad in one fraction calculated to the 90% isodose. Survival and patterns of failure were analyzed by site and treatment method. All four patients with GB carcinoma are dead of disease at 5 1/2, 6, 9 and 10 months from the date of diagnosis respectively. Three of the four developed diffuse peritoneal carcinomatosis. Five of the 16 patients with EHBD carcinoma are alive with a median follow-up of 18 months (range 6-23 months). Four of the 5 patients received a transcatheter 192Ir or IORT boost and all are without evidence of disease. Four of 9 patients who had a subtotal resection with transection of tumor, dilatation of the bile ducts with probes or curettement of the bile ducts developed either diffuse peritoneal carcinomatosis (3 patients) or a recurrence in the surgical scar (2 patients). Local failure was documented in 3 of the nine patients treated with external beam alone +/- 5-FU, and has been documented in one of the seven patients who received an IORT or transcatheter 192Ir boost. Further experience is necessary to determine whether this aggressive treatment will result in long-term disease-free survival in these patients.

Adult↗
PubMed1982

Primary retroperitoneal seminoma.

In a retrospective review (1950-1975) of the Mayo Clinic experience with seminomas (483 cases), twelve patients (2.5%) were found to have a retroperitoneal seminoma without evidence of testicular involvement. The mean age was 47 years (range, 31-67). Eleven patients were treated by radiation alone, with doses ranging from less than 2,000-5,800 rads. Seven patients are alive with a median follow-up of six years. The median survival of the five that died is ten months. Good prognostic factors are typical histopathology and an encapsulated tumor. Poor prognostic factors are atypical histopathology, a nonencapsulated tumor, a symptomatic abdominal mass and a nonfunctioning kidney at the time of diagnosis. Although the review includes few patients, it seems reasonable to suggest irradiation of the tumor bed and para-aortic lymph nodes to a minimum dose of 2,000 rads. Prophylactic treatment of the mediastinum and supraclavicular lymph nodes should be considered if one or more of the poor prognostic factors are present.

Adult↗
PubMedDate not supplied

Base of tongue carcinoma: patterns of failure and predictors of recurrence after surgery alone.

Between January 1971 and December 1986, 55 patients with squamous cell carcinoma of the tongue base underwent complete surgical resection with curative intent. No preoperative or postoperative adjuvant therapy was administered. The study group consisted of 41 men and 14 women (median age 61 years). All patients were followed until death (39 patients) or for a median of 9.4 years. Local control at 5 years was 74%. No predictors of local recurrence were discovered. Control in the dissected neck at 5 years was 68%. Control of cancer above the clavicles at 5 years was 48%. Distant metastases developed in 14% of the patients by 5 years. Cause-specific survival at 5 years was 65%. A Cox multivariate regression analysis revealed that pathologic N stage was the only significant independent predictor of recurrence in the dissected neck, recurrence above the clavicles, and cause-specific survival. The 5-year overall survival was 55%. Surgical mortality was 4%.

Adult↗
PubMedDate not supplied

Laryngectomy alone for T3 glottic cancer.

BACKGROUND: The long-term survival of 81 patients with T3 squamous cell carcinoma of the glottic larynx treated with laryngectomy alone is presented and pathologic predictors for cancer recurrence above the clavicles and cancer death are identified. METHODS: Clinical records, operative notes, and pathologic slides were reviewed. The major end points were failure above the clavicles, cause-specific survival, and overall survival. All patients were followed until death or a minimum of 10.8 years. RESULTS: The main pattern of treatment failure was within an undissected ipsilateral or contralateral neck. Subglottic extension and nodal metastases predicted failure above the clavicles and delayed metastasis within an undissected neck. The 5-year rate of control of disease above the clavicles, cause-specific survival, and overall survival were 74.1%, 73.7%, and 54.3%, respectively. CONCLUSIONS: Patients treated with laryngectomy for T3 glottic cancer who have pathologic evidence of subglottic extension or nodal metastasis are at higher risk for recurrence above the clavicles, particularly within an undissected neck.

Adult↗