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Biomedical subjects

B McCormick

Publications and source records attributed to B McCormick.

At least 73 records · Page 4Linked to original sources
PubMed1994

Effects of beam modifiers and immobilization devices on the dose in the build-up region.

PURPOSE: To analyze the effect that immobilization devices used in conjunction with beam modifiers may have on the dose to the skin and build-up region. METHODS AND MATERIALS: Central axis depth dose measurements were made in a polystyrene phantom in the build-up regions using the 6 and 15 MV photon beams, at two different source-to-phantom distances, and various field sizes. The effects of acrylic blocking trays, lead wedges, and cerrobend blocks were assessed in conjunction with the enhancement of dose in the build-up region due to immobilizing devices using plaster and thermoplastic casting materials of different thicknesses. RESULTS: For the 6 MV photons, solid (3 mm) thermoplastic casting material was found to have the greatest effect on surface dose: for a 12 x 12 cm field we measured 79% of maximum dose when treating through the material versus 22% of maximum dose when no beam modifiers or immobilization devices are used. Measurements were also made to evaluate the effect of the immobilization of patients receiving three-dimensional conformal treatments using a 15 MV photon beam. CONCLUSIONS: The relevance of these results to treatments in the pelvis, breast, and head and neck regions is discussed. For 6 MV beams, special consideration should be given if the need arises to treat through the immobilization device, as unacceptable skin reactions may result.

Dose-Response Relationship, Radiation↗
PubMed1994

Selection criteria for breast conservation. The impact of young and old age and collagen vascular disease.

BACKGROUND: Selection criteria applicable to women desiring breast-conserving surgery and radiation for early invasive breast cancer have evolved over the last decade. The presence of active collagen vascular disease has emerged as a contraindication for this treatment. The roles of both young and old age have been debated by many authors, although a growing body of literature supports the impact of age on both local control and disease free survival. METHODS: This is a review of the literature addressing these selection criteria. RESULTS: A consensus exists regarding the impact of preexisting collagen vascular disease on the anticipated complications with breast-conserving radiation, despite small numbers reported. A young age, although not always a statistically significant factor, emerges as a consistent predictor for both local and distant failures. This is true not only for patients who opt for breast conservation but also those who are treated with mastectomy. To the contrary, preliminary data suggests that older age is emerging as a predictor for improved local and regional control. CONCLUSIONS: Preexisting collagen vascular disease is a contraindication for the use of breast-conserving radiation and surgery. Extremes of age must be considered in terms of recommending not so much a specific local regional treatment, but an overall strategy. For the very young patient with breast cancer, more aggressive systemic therapy should be considered in addition to the appropriate local regional therapy. For the elderly, preliminary pilot studies suggest that tamoxifen may play a role in local as well systemic control, perhaps opening the door for future trials examining the need for radiation in selected elderly patients.

Adult↗
PubMed1994

Trilateral retinoblastoma--incidence and outcome: a decade of experience.

PURPOSE: This report examines the incidence and outcome of trilateral retinoblastoma in children treated for retinoblastoma. A group of patients who are at highest risk for the development of trilateral retinoblastoma is defined. METHODS AND MATERIALS: Between 1979 and 1990, 117 children were treated with external beam radiation therapy for retinoblastoma, (97/117, bilateral). Median follow-up time was 68 months. The median age at diagnosis was 7 months. RESULTS: Six cases of trilateral retinoblastoma were identified. The incidence of trilateral retinoblastoma in children with bilateral retinoblastoma was 6% (6/97) and 10% in those with a family history of retinoblastoma. The median age at diagnosis of RB in the children with trilateral retinoblastoma, was 3 months, younger than the median age of the entire retinoblastoma group. In all cases, the pineal region was excluded from the radiotherapy fields. Treatment for the trilateral retinoblastoma consisted of craniospinal axis radiation therapy and chemotherapy in three patients, chemotherapy alone in two, and no treatment in one. All patients died from this disease. Overall, of the 117 children treated at our institution for retinoblastoma with a median follow-up of 68 months, 12 have died. Trilateral retinoblastoma was the major cause of death, accounting for 50% (6/12) of deaths. CONCLUSION: Trilateral retinoblastoma is a major and under-appreciated cause of mortality in the first 5 years after the diagnosis of bilateral retinoblastoma. A more aggressive approach toward screening a defined population of childhood retinoblastoma survivors may be warranted.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Breast cellulitis after conservative surgery and radiotherapy.

PURPOSE: Cellulitis is a previously unreported complication of conservative surgery and radiation therapy for early stage breast cancer. Patients who presented with breast cellulitis after conservative therapy are described. METHODS AND MATERIALS: Eleven patients that developed cellulitis of the breast over a 38-month period of observation are the subject of this report. Clinical characteristics of patients with cellulitis and their treatment and outcome are reported. Potential patient and treatment-related correlates for the development of cellulitis are analyzed. RESULTS: The risk of cellulitis persists years after initial breast cancer therapy. The clinical course of our patients was variable: some patients required aggressive, long-duration antibiotic therapy, while others had rapid resolution with antibiotics. Three patients suffered from multiple episodes of cellulitis. CONCLUSION: Patients with breast cancer treated with conservative surgery and radiotherapy are at risk for breast cellulitis. Systematic characterization of cases of cellulitis may provide insight into diagnosis, prevention, and more effective therapy for this uncommon complication.

Acute Disease↗
PubMed1994

Radiation therapy for breast cancer.

Prospective randomized studies continue to dominate issues of local regional radiation therapy for breast cancer. The National Surgical Adjuvant Breast and Bowel Project, designed to assess the role of radiation therapy in the management of breast-conserving surgery for duct carcinoma in situ, has published preliminary results. These results indicate that the use of radiation therapy decreases the local recurrence rate in women with this disease, with a short median follow-up for the entire group so far. The Milan Cancer Institute likewise first reported on their trial assessing the role of radiation therapy in early invasive breast cancer, following a quadrantectomy procedure in the breast as well as an axillary node dissection. Again, radiation therapy significantly decreased the local recurrence rate in the treated breast compared with observation alone. Several important retrospective analyses continue to search for prognostic indicators that might effect the outcome of patients treated with breast-conserving surgery and irradiation. The issue of early age, as well as the issue of sequencing needed adjuvant chemotherapy with whole-breast irradiation was the subject of several articles. Other researchers focused on methods of detection of failure in the irradiated breast, including several innovative studies using magnetic resonance imaging. Documentation of radiation-related treatment sequelae is also reviewed, along with a retrospective study assessing the palliative role of strontium-89 isotope treatment of women with widespread metastatic bone lesions.

Breast Neoplasms↗
PubMed1993

Inhibition of cell motility after nm23 transfection of human and murine tumor cells.

Abstract nm23 gene expression has been inversely correlated with tumor metastatic potential in certain tumors including melanomas, breast carcinomas, and hepatocellular carcinomas. The cellular mechanisms by which the nm23 protein may directly or indirectly modulate the metastatic phenotype is not yet known. Because cell motility plays an essential role in metastatic dissemination, we have studied whether tumor cells transfected with nm23 complementary DNA have any alterations in their ability to migrate. Our results demonstrate that nm23 transfection inhibits the ability of murine melanoma and human breast carcinoma cells to migrate in response to serum or to defined factors such as platelet derived growth factor or insulin-like growth factor 1. Random, unstimulated cell motility was not depressed in the nm23 transfectants. The results suggest that the nm23 gene product may interact with intracellular molecules that are essential for stimulated cell motility in two different tumor cell systems.

Animals↗
PubMed1993

Ductal carcinoma in situ (intraductal carcinoma) of the breast treated with breast-conserving surgery and definitive irradiation. Correlation of pathologic parameters with outcome of treatment.

BACKGROUND: To evaluate the pathologic characteristics of the primary tumor relative to local control, survival, and freedom from distant metastases, an analysis was performed of 172 patients with ductal carcinoma in situ (intraductal carcinoma) of the breast treated with breast-conserving surgery and definitive breast irradiation. METHODS: The clinical records and pathology slides were reviewed from 172 women with ductal carcinoma in situ treated with breast-conserving surgery and definitive breast irradiation at multiple institutions in Europe and the United States. Central pathology review was performed by one pathologist without knowledge of the clinical outcome. The clinical outcome was measured in terms of local control, overall survival, cause-specific survival, and freedom from distant metastases. The median follow-up time was 84 months (range, 17-177 months). RESULTS: The pathologic parameters evaluated were histologic subtype, nuclear grade, amount of necrosis, and final pathology margin. The only pathologic parameter that correlated with the rate of local recurrence was the presence versus the absence of the combination of the histologic subtype of comedo carcinoma plus nuclear grade 3 (8-year actuarial rate of local recurrence of 20% versus 5%, respectively; P = 0.009 on univariate analysis; P = 0.017 on multivariate analysis). None of the pathologic parameters evaluated correlated with overall survival (all P > or = 0.16), cause-specific survival (all P > or = 0.13), or freedom from distant metastases (all P > or = 0.13). CONCLUSIONS: These results have demonstrated that there are important differences in the rate of local recurrence based on the pathologic characteristics of the primary tumor for women with ductal carcinoma in situ treated with breast-conserving surgery and definitive irradiation. However, the differences in local recurrence have not been associated with differences in survival or freedom from distant metastases. Careful follow-up for patients at increased risk for local recurrence is warranted because of the potential ability to salvage patients with local recurrence.

Adult↗
PubMed1993

Radiation therapy for breast cancer.

Local regional control, despite its lack of impact on survival, continues to be recognized as an important end point in and of itself. In addition to recent updates on conservation studies demonstrating this dichotomy, local regional radiation is now playing an important role in the management of advanced breast cancer postmastectomy. The most extreme example of this importance is its inclusion in autologous bone marrow transplantation programs. Documentation of the long-term outcome of breast or chest wall radiation, in terms of both complications and treatment failures, appears increasingly in this year's literature. With sophisticated biostatistical analysis of all factors predicting for both local failure and late complications, patient selection for these treatments should become easier for both the woman and her physician.

Adult↗
PubMed1993

Late partial recovery from meningitic deafness after cochlear implantation: a case study.

A child with well-documented total bilateral deafness as a result of meningitis contracted at the age of 2 years and 8 months demonstrated remarkably delayed recovery of hearing 14 months later. In the meantime cochlear implantation had been performed. Hearing returned partially in the nonimplanted ear and also in the ear implanted with a long multi-electrode intracochlear array, giving unaided thresholds at frequencies from 0.5 to 4 kHz of 60-80 dB and 90-105 dB, respectively. Despite this rare occurrence, it is concluded that a delay until 6 months after meningitis before implantation is appropriate to detect most cases of spontaneous recovery of hearing.

Auditory Threshold↗
PubMed1992

Detection of local recurrence after conservative therapy for breast carcinoma.

BACKGROUND: Early detection of local recurrence after conservative therapy for breast cancer is associated with improved survival. This review was undertaken to determine the ability to detect recurrence and identify patterns of recurrence. METHODS: Records of women with local tumor recurrence were retrospectively reviewed. RESULTS: In 42 women with 43 local recurrences, tumors were detected by mammography alone in 18 instances (42%), physical examination alone in 14 (33%), and by both in 11 (25%). Of 29 recurrences mammographically detected, 19 were diagnosed by microcalcifications, 9 by a mass, and 1 by a mass with microcalcifications. Twenty of 25 tumors detected by physical examination were felt as a mass. Recurrences detected by mammography were more often in situ (72% or 13 of 18) than those detected by physical examination alone (7% or 1 of 14). Treatment failure at the site of the original tumor seemed to occur earlier than failures elsewhere in the breast and was more common in women younger than 43 years of age or with disease that was originally axillary node-positive. CONCLUSIONS: Mammography often detects more in situ recurrences than physical examination, but both are complimentary. Recurrence at the site of the original tumor is usually earlier and in younger women and may be associated with tumors that were originally node-positive.

Adult↗
PubMed1992

Four cycles of chemotherapy and regional radiation therapy for clinical early-stage and intermediate-stage Hodgkin's disease.

To achieve a high percentage of durable complete remissions (CR) and prolonged survivals and reduce toxicity in patients with early-stage and intermediate-stage Hodgkin's disease, a randomized trial of four cycles of mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) versus four cycles of thiotepa, bleomycin, and vinblastine (TBV) combined with regional radiation therapy (RT) was conducted. For MOPP and RT, the CR percentage was 98% (60 of 61), and at 5 years, the percentage of patients in CR was 90%, with freedom from progression of 89% and overall survival of 91%. For TBV and RT, the CR percentage was 93% (55 of 59), with a 5-year duration of CR of 83%, freedom from progression of 81%, and overall survival of 91% (P greater than 0.15). The median follow-up was 65 months (range, 7 to 96 months). For 27 patients with clinical Stage IIIA, the CR percentage for MOPP and RT was 75% (12 of 16), with 1 relapse and 4 deaths. For TBV and RT, the CR percentage for clinical Stage IIIA was 73% (8 of 11) with 2 relapses and 2 deaths. Short-term toxicity except for transient leukopenia was less for TBV and RT than for MOPP and RT. Good results are achievable with combined treatment without excessive toxicity.

Adolescent↗
PubMed1992

Infiltrating breast carcinoma in patients age 30 years and younger: long term outcome for life, relapse, and second primary tumors.

A retrospective study examining the influence of young age, defined as 30 years or less on the outcome of early-staged (American Joint Committee 1978-I, II) breast cancer was undertaken using patients treated between 1950 and 1970 to ensure a long follow-up period. Because of the era of treatment, radical mastectomy without systemic chemotherapy was the predominant treatment. Ninety-nine patients met study criteria, with a median follow-up of 11.4 years (range 0.5 to 41 years). The patient group was compared to patients of all ages, treated at Memorial Sloan-Kettering Cancer Center in 1960 (5 and 10 years) and to patients treated between 1940 and 1943 (30 year follow-up). At the 5, 10, and 30 year follow-up periods, patients in the young age group consistently had disease-specific survival 10-20% lower than their older counterparts. For young patients who survived their first cancer diagnosis, second primaries both in the contralateral breast and elsewhere, played a significant role in determining their subsequent life span. When compared to risks of second primary cancers in the National Cancer Institute's SEER (Surveillance, Epidemiology and End Results Program) Cancer Registry for all ages, the increased risk for very young breast cancer patients was significant (p = 0.000). With these two findings in mind, treatment for young patients with breast cancer should focus not on local therapy options alone but on the increased risk of both systemic disease and of second primaries.

Adolescent↗
PubMed1992

Radiation therapy for breast cancer.

Now that the radiation literature for breast cancer is well established in terms of both local control and survival endpoints, especially for invasive breast cancer, recent reports focus on refining selection criteria of patients for treatment and on minimizing complications and maximizing cosmetic effects. The optimal treatment of patients with ductal carcinoma in situ remains a controversial issue, and the optimal sequencing of adjuvant chemotherapy and primary radiation in patients with breast-conserving surgery is emerging as a topic requiring further study.

Brachytherapy↗
PubMed1992

The paediatric otological caseload resulting from improved screening in the first year of life.

Improved test technique by health visitors has been shown to lead to higher accuracy in the screen of hearing aimed traditionally at prelingual sensorineural deafness. However, it gives greatly increased referrals of children having otitis media with effusion (OME) around the end of the first year of life. Two samples of children (n = 29 and 61) were tested in a children's hearing assessment clinic with properly documented testing techniques and trained personnel. The samples were each formed on a fixed population base, one before and one after screen improvements. This enabled characterization of two outcome groups within each sample (severe/persistent enough to refer to ENT vs discharged, despite slight hearing impairment). The average audiometric criterion for onward referral to ENT rose only very little, despite the increased assessment caseload resulting from more detections by the screen. This usefully permitted the conclusion that the number of true cases found due to the screen and assessed as lying beyond a specifiable degree of severity (average cut-off approximately 47 dB(A) or 35 dBHTL) had increased not through lower criteria for referral to ENT, but through the improvements to the screen. The increase was from approximately 0.4% to 1.3% of the base population screened. Thus a change materially enhancing the sensitivity and positive predictive value of a screen considerably enlarges the eventual otological caseload of children with middle-ear disease thought to justify concern at around the end of their first year. If done properly, screening is hence in practical terms about OME, not about prelingual sensorineural hearing impairment. This conclusion presses the urgency of evaluation and consensus on the otological management of the young child with OME.

Analysis of Variance↗
PubMed1992

Choroidal melanoma responses after brachytherapy treatment.

Serial ultrasonic measurements performed on 85 melanoma patients who were treated with radioactive plaques and followed for up to 141 months revealed that no 2 patients had identical patterns of change. Eighty-two of the patients were categorized into one of four patterns after treatment: Type D (decrease in height, 57 patients), Type S (same height, 12 patients), Type I (increase in height, 9 patients), and Type RG (tumour regrowth, 4 patients). The calculated mean total change in tumor height for Type D was 1.92 mm at 6 months, 2.58 mm at 12 months, 2.97 mm at 24 months and 3.61 mm at 48 months. For Type I, the mean total change in tumor height was 0.80 mm at 6 months, 0.95 mm at 12 months, 2.28 mm at 24 months, and 3.0 mm at 48 months.

Brachytherapy↗