Biomedical subjects

Robert L Foote

Publications and source records attributed to Robert L Foote.

31 records · Page 2Linked to original sources

PubMed2003

Parathyroid carcinoma: is there a role for adjuvant radiation therapy?

BACKGROUND: The authors proposed to determine risk factors associated with postoperative progression of parathyroid carcinoma within the neck (locoregional) and to assess the efficacy of postoperative adjuvant radiation therapy in preventing disease progression within the neck. METHODS: A retrospective review of patients with pathologically confirmed parathyroid carcinoma who underwent surgical resection was performed. Risk factors identified on univariate analysis were applied in a proportional hazards analysis to identify significant independent predictors of locoregional disease progression and cause-specific survival after surgical resection. Fifty-seven patients were treated with surgery alone (no adjuvant radiation therapy [RT]) and were determined to have sufficient follow-up and pathologically confirmed features to be included in the current analysis. Four patients were treated with surgery and adjuvant RT. Four patients received RT to the neck and mediastinum for unresectable locoregional disease progression. Patients were followed for a median of 75.6 months (range, 8.4-358 months). RESULTS: Twenty-five patients (44%) developed locoregional disease progression at a median of 27.1 months after surgery (range, 6.2-138.3 months). The univariate analysis revealed that surgical margin status and the institution at which the initial surgery was performed were predictive of locoregional progression-free survival. The institution at which the initial surgery was performed was found to be an independent predictor of cause-specific survival. Of the four patients treated with surgery and adjuvant RT, all were alive and without disease at the time of last follow-up. All four patients who received RT for locoregional disease progression after initial surgery achieved locoregional disease control. CONCLUSIONS: Patients with parathyroid carcinoma are reported to have a significant risk of locoregional disease progression after surgery alone. The results of the current study demonstrated that the risk of postoperative disease progression can be predicted by surgical margin status and the institution at which the initial surgery is performed. Patients treated with surgery and postoperative RT may have a lower risk of locoregional disease progression and improved cause-specific survival. RT can be used to provide locoregional control of recurrent disease.

Aged↗

PubMed2003

Is there a role for radiation therapy in the management of Hürthle cell carcinoma?

PURPOSE: To determine the role that radiation therapy may have in the management of resected, unresectable, and metastatic Hürthle cell carcinoma. METHODS AND MATERIALS: Retrospective review of 18 patients receiving radiation therapy for Hürthle cell carcinoma of the thyroid gland. The diagnosis was established in 10 men and 8 women between November 1943 and January 1995. Median age was 57.9 years. Initially, 5 patients received adjuvant radiation therapy, 7 received salvage radiation therapy for unresectable recurrent disease, and 6 received palliative radiation therapy for distant metastases. Median follow-up was 107.1 months (range 15.7-351 months). The Kaplan-Meier method was used to calculate and estimate overall survival, cause-specific survival, and locoregional tumor control rate. RESULTS: The 5-year overall and cause-specific survival rates were 66.7% (SE 11.1%) and 71.8% (SE 10.7%), respectively. Adjuvant radiation therapy was successful in preventing recurrence in 4 of 5 patients. Salvage radiation therapy was successful in 3 of 5 patients treated with external beam radiation therapy. Palliative radiation therapy provided sustained symptomatic relief at 67% of irradiated sites. CONCLUSIONS: Hürthle cell carcinoma of the thyroid gland is a radiosensitive tumor. Radiation therapy may provide palliative relief from symptomatic metastases, control recurrent tumors, and prevent recurrence of advanced resected tumors.

Adenoma, Oxyphilic↗

PubMed2003

A study on the radiation tolerance of the optic nerves and chiasm after stereotactic radiosurgery.

PURPOSE: To evaluate the risk of clinically significant radiation optic neuropathy (RON) for patients having stereotactic radiosurgery of benign tumors adjacent to the optic apparatus. METHODS AND MATERIALS: We reviewed the dose plans and clinical outcomes of 218 gamma knife procedures (215 patients) for tumors of the sellar and parasellar region (meningiomas, n = 122; pituitary adenomas, n = 89; craniopharyngiomas, n = 7 patients). Previous surgery or radiation therapy was performed in 156 (66%) and 24 (11%) patients, respectively. Median follow-up was 40 months (range 4-115). RESULTS: The median maximum radiation dose to the optic nerve was 10 Gy (range 0.4-16.0). Four patients (1.9%) developed RON at a median of 48 months after radiosurgery. All had prior surgery, and 3 of 4 had external beam radiotherapy (EBRT) in their management either before (n = 2) or adjuvantly (n = 1). The risk of developing a clinically significant RON was 1.1% for patients receiving 12 Gy or less. Patients receiving prior or concurrent EBRT had a greater risk of developing RON after radiosurgery (p = 0.004). CONCLUSION: RON occurred in less than 2% of our patients, despite the majority (73%) receiving more than 8 Gy to a short segment of the optic apparatus. Knowledge of the dose tolerance of these structures permits physicians to be more aggressive in treating patients with sellar or parasellar tumors, especially those with hormone-producing pituitary adenomas that appear to require higher doses to achieve biochemical remission.

Adenoma↗

PubMed2003

Intraoperative radiotherapy for head and neck and skull base cancer.

BACKGROUND: The purpose of this study was to evaluate the use of intraoperative electron beam radiotherapy (IORT) as an adjuvant modality in the treatment of advanced head and neck and skull base cancer. METHODS: Between 1991 and 1996, 34 patients with squamous cell carcinoma (SCCA) and 10 patients with non-SCCA were enrolled in this prospective nonrandomized clinical trial. Most patients had been previously treated with combinations of surgery, external beam radiotherapy, and chemotherapy. The most frequent sites treated were the skull base (56%) and the neck (44%). IORT was delivered in a dedicated operating room suite with energies of 6 to 15 MeV (6 MeV most commonly used) at doses of 12.5 to 22.5 Gy. RESULTS: At 2 years overall and disease-free survival was 32% and 21%, respectively, for the SCCA patients and 50% and 40%, respectively, for the non-SCCA patients. Tumor control rates at 2 years in the IORT field were 46% for the SCCA patients and 52% for the non-SCCA patients. For squamous cell histology, survival in patients with microscopic residual tumor did not differ from those with no residual tumor, but they both had significantly longer disease-free survival than those patients with gross residual at the time of IORT (p =.03), with a trend toward longer overall survival (p =.09). The only complication directly attributable to IORT was a neuropathy in a patient who received an IORT dose of 22.5 Gy (cumulative dose 130.1 Gy). CONCLUSIONS: IORT at a dose of 12.5 Gy is safe and produces tumor control and survival for patients likely to have microscopic residual disease in sites difficult to resect such as the skull base.

Adolescent↗

PubMed2003

Properly selected patients with multiple brain metastases may benefit from aggressive treatment of their intracranial disease.

To determine whether properly selected patients with multiple brain metastases benefit from aggressive treatment of their intracranial disease, we reviewed 52 patients having stereotactic radiosurgery (SRS), tumor resection, or both between April 1997 and March 2000. Tumor histology included lung (n = 18, 35%), breast (n = 11, 21%), renal (n = 6, 12%), melanoma (n = 6, 12%), and other (n = 11, 21%). The median patient age was 58 years, the median Karnofsky performance status (KPS) was 90, and the median number of tumors was three. Twenty patients (39%) had progressed after prior radiation therapy. Treatment included multiple craniotomies and tumor resection (n = 5, 10%), radiosurgery (n = 31, 60%), or resection and radiosurgery (n= 16, 30%). Median survival was 15.5 months. The one- and two-year actuarial survivals were 63% and 27%, respectively. Multivariate analysis found radiation therapy oncology group recursive partitioning analysis (RTOG RPA) Class (1 vs. 2/3) correlated with improved survival (Relative risk = 2.60, 95% CI 1.13-5.97, p = 0.03). Class 1 patients (KPS > or = 70, age < 65 years, and controlled primary with no extracranial metastases) survived a median of 19 months whereas Class 3 patients (KPS < 70) survived 8 months. Class 2 patients (all other patients) survived a median of 13 months. Thirty-five patients (67%) had intracranial progression at a median of 8.0 months. Intracranial progression was local (n = 6), distant (n = 23), or local and distant (n = 6); 26 patients with intracranial progression underwent additional brain tumor treatments. Multivariate analysis found patients with radiosensitive tumors (lung, breast, other) had fewer intracranial recurrences compared to patients with radio-resistant tumors (melanoma, renal, sarcoma) (Relative risk = 2.43, 95% CI 1.13-5.10, p = 0.02). The length of survival in our series is quite comparable to historical reports on the management of brain metastasis patients, and supports aggressive intervention for RTOG RPA Class 1 patients and Class 2 patients with controlled primary disease who have a limited number of brain metastases.

Adult↗

PubMed2003

Swallow function in patients before and after intra-arterial chemoradiation.

OBJECTIVES/HYPOTHESIS: To prospectively evaluate swallow function in patients with advanced head and neck cancer before and after completion of intra-arterial chemoradiation therapy and planned neck dissection. STUDY DESIGN: Prospective nonrandomized study. METHODS Swallow function was evaluated in 11 patients with resectable T4 and selected T3 head and neck cancer before and, on average, 19 weeks after completion of treatment. RESULTS: The Performance Status Scale demonstrated worse scores for both eating in public (P =.004) and normalcy of diet (P =.004) after treatment. Patients who underwent neck dissections had significantly worse scores (P =.02) in normalcy of diet. A significant decline was noted in swallowing functional measures at the time of the repeat evaluation (P =.02). Videofluoroscopic swallow studies revealed altered swallow function in 9 of 11 patients before treatment, with aspiration seen in 3 patients. Following treatment, the incidence of aspiration increased to seven patients. Tongue base retraction, reduced laryngeal elevation, and increased laryngeal vestibule penetration of thick liquid were all statistically significantly worse after treatment. The overall score on the quality of life instrument was not significantly changed from before to after treatment. CONCLUSIONS: The majority of patients demonstrated significantly worse swallow function on all three methods of analysis at 19 weeks after completion of treatment. Continued detailed monitoring of patients' swallow function is critical in determining long-term effects of intra-arterial chemoradiation therapy and neck dissection.

Adult↗

PubMed2002

Stereotactic radiosurgery: the preferred management for patients with nonvestibular schwannomas?

PURPOSE: To review patient outcomes after radiosurgery of nonvestibular schwannomas. MATERIALS AND METHODS: From April 1992 to February 2000, 23 patients had radiosurgery at our center for nonvestibular schwannomas. Affected cranial nerves included the trochlear (n = 1), trigeminal (n = 10), jugular foramen region (n = 10), and hypoglossal (n = 2). Nine patients had undergone one or more prior tumor resections. One patient had a malignant schwannoma; 2 patients had neurofibromatosis. The median prescription isodose volume was 8.9 cc (range, 0.2 to 17.6 cc). The median tumor margin dose was 18 Gy (range, 12 to 20 Gy); the median maximum dose was 36 Gy (range, 24 to 40 Gy). The median follow-up after radiosurgery was 43 months (range, 12 to 111 months). RESULTS: Twenty-two of 23 tumors (96%) were either smaller (n = 12) or unchanged in size (n = 10) after radiosurgery. One patient with a malignant schwannoma had tumor progression outside the irradiated volume despite having both radiosurgery and fractionated radiation therapy (50.4 Gy); he died 4 years later. Morbidity related to radiosurgery occurred in 4 patients (17%). Three of 10 patients with trigeminal schwannomas suffered new or worsened trigeminal dysfunction after radiosurgery. One patient with a hypoglossal schwannoma had eustachian tube dysfunction after radiosurgery. No patient with a lower cranial nerve schwannoma developed any hearing loss, facial weakness, or swallowing difficulty after radiosurgery. CONCLUSIONS: Although the reported number of patients having radiosurgery for nonvestibular schwannomas is limited, the high tumor control rates demonstrated after vestibular schwannoma radiosurgery should apply to these rare tumors. Compared to historical controls treated with surgical resection, radiosurgery appears to have less treatment-associated morbidity for nonvestibular schwannomas, especially for schwannomas involving the lower cranial nerves.

Adolescent↗

PubMed2002

Glomus jugulare tumor: tumor control and complications after stereotactic radiosurgery.

BACKGROUND: We evaluated toxicity and long-term efficacy of stereotactic radiosurgery in patients with symptomatic or progressive glomus jugulare tumors. METHODS: Twenty-five consecutive patients (age, 30-88 years; 17 women, 8 men) who underwent stereotactic radiosurgery with the Leksell Gamma Knife (dose, 12-18 Gy) were prospectively followed. MRI and clinical examinations were performed at 6 months and 1, 2, and 3 years, and then every 2 years. RESULTS: None of the tumors increased in size, 17 were stable, and 8 decreased (median imaging follow-up, 35 months; range, 10-113 months). Symptoms subsided in 15 patients (60%); vertigo occurred in 1, but balance improved with vestibular training (median clinical follow-up, 37 months; range, 11-118 months). No other new or progressive neuropathy of cranial nerves V-XII developed. CONCLUSIONS: Stereotactic radiosurgery can achieve excellent tumor control with low risk of morbidity in the treatment of glomus jugulare tumors. The lower cranial nerves can safely tolerate a radiosurgical dose of 12 to 18 Gy.

Adult↗

PubMed2002

Intensity-modulated radiation therapy for head and neck cancer: emphasis on the selection and delineation of the targets.

The head and neck contain many critical, noninvolved structures in close vicinity to the targets. The tightly conformal doses produced by intensity-modulated radiation therapy (IMRT), and the lack of internal organ motion in the head and neck, provide the potential for organ sparing and improved tumor irradiation. Many studies of treatment planning for head and neck cancer have demonstrated the dosimetric superiority of IMRT over conventional techniques in these respects. The initial results of clinical studies demonstrate reduced xerostomia. They suggest an improvement in tumor control, which needs to be verified in larger studies and longer follow-up. Critical issues for successful outcome of head and neck IMRT are accurate selection of the neck lymph nodes that require adjuvant treatment, and accurate delineation on the planning computed tomography (CT) of the lymph-node bearing areas and subclinical disease adjoining the gross tumor. This review emphasizes these topics and provides some guidelines.

Head and Neck Neoplasms↗

PubMed2002

Stereotactic radiosurgery for idiopathic trigeminal neuralgia.

OBJECT: Each year a greater number of patients with trigeminal neuralgia (TN) undergo radiosurgery, including a large number of patients who are candidates for microvascular decompression (MVD). METHODS: The case characteristics and outcomes of 117 consecutive patients who underwent radiosurgery were retrieved from a prospectively maintained database. The mean patient age was 67.8 years; and the majority (58%) of patients had undergone surgery previously. The dependent variable for all analyses of facial pain was complete pain relief without medication (excellent outcome). Median follow-up duration was 26 months (range 1-48 months). The actuarial rate of achieving and maintaining an excellent outcome was 57% and 55% at 1 and 3 years, respectively, after radiosurgery. A greater percentage of patients who had not previously undergone surgery achieved and maintained excellent outcomes (67% at 1 and 3 years) than that of patients who had undergone prior surgery (51% and 47% at 1 and 3 years, respectively; relative risk [RR] = 1.77, 95% confidence interval [CI] 1.01-3.13, p = 0.04). New persistent trigeminal dysfunction was noted in 43 patients (37%). Tolerable numbness or paresthesias occurred in 29 patients (25%), whereas bothersome dysesthesias developed in 14 patients (12%). Only a radiation dose of 90 Gy correlated with new trigeminal deficits or dysesthesias (RR = 3.10, 95% CI 1.64-5.81, p < 0.001). Excellent outcomes in patients with new trigeminal dysfunction were achieved and maintained at rates of 76% and 74% at 1 and 3 years, respectively, after radiosurgery, compared with respective rates of 46% and 42% in patients who did not experience postradiosurgery trigeminal dysfunction (RR = 4.53, 95% CI 2.03-9.95, p < 0.01). CONCLUSIONS: Radiosurgical treatment provides complete pain relief for the majority of patients with idiopathic TN. There is a strong correlation between the development of new facial sensory loss and achievement and maintenance of pain relief after this procedure. Because the long-term results of radiosurgery still remain unknown, MVD should continue to be the primary operation for medically fit patients with TN.

Actuarial Analysis↗

PubMed2002

Results of stereotactic radiosurgery in patients with hormone-producing pituitary adenomas: factors associated with endocrine normalization.

OBJECT: The goal of this study was to determine factors associated with endocrine normalization after radiosurgery is performed in patients with hormone-producing pituitary adenomas. METHODS: Between 1990 and 1999, 43 patients with hormone-producing pituitary adenomas underwent radiosurgery: 26 patients with growth hormone (GH)-producing tumors, nine with adrenocorticotrophic hormone-producing tumors, seven with tumors that produced prolactin (PRL) alone, and one with a tumor that secreted both GH and PRL. The median patient age was 42 years. Thirty-seven patients (86%) had undergone surgery earlier and in 30 (70%) there was tumor extension into the cavernous sinus. The product-limit method was used to calculate endocrine normalization while patients were not receiving any hormone-suppressive medication. The median follow-up period after radiosurgery was 36 months (range 12-108 months). In 20 patients (47%) there was normalization of hormone secretion at a median of 14 months (range 2-44 months) after radiosurgery; no correlation was found between tumor type and cure. Actuarial cure rates were 20, 32, and 61% at 1, 2, and 4 years posttreatment. Multivariate analysis demonstrated that the absence of hormone-suppressive medications at the time of radiosurgery (relative risk 8.9, 95% confidence interval [CI] 1.2-68.7, p = 0.04) and maximum radiation doses greater than 40 Gy (relative risk 3.9, 95% CI 1.3-11.7, p = 0.02) correlated with an endocrine cure. A new anterior pituitary deficiency developed in seven patients (16%), temporal lobe necrosis was identified in two patients, an asymptomatic internal carotid artery stenosis was detected in two patients, and unilateral blindness occurred in one patient. CONCLUSIONS: Radiosurgery provides an endocrine cure for many patients with persistent or recurrent hormone-producing pituitary adenomas. Further study is needed to determine whether pituitary hormone-suppressive medications have a radioprotective effect.

Acromegaly↗

PubMed2002

Stereotactic radiosurgery for patients with "radioresistant" brain metastases.

OBJECTIVE: Our aim was to evaluate the efficacy of stereotactic radiosurgery (SRS) for the treatment of patients with brain metastases that have been determined to be "radioresistant" on the basis of histological examination. METHODS: We reviewed the medical records of 41 consecutive patients who presented with 83 brain metastases from radioresistant primaries and subsequently underwent SRS. All patients were followed until death or for a median of 31 months after SRS. Tumor histologies included renal cell carcinoma (16 patients), melanoma (23 patients), and sarcoma (2 patients). Eighteen patients (44%) had a solitary metastasis, and 23 patients (56%) had multiple metastases. RESULTS: The median overall survival time was 14.2 months after SRS. On the basis of univariate analysis, systemic disease status (P = 0.006) and Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class (P = 0.005) were associated with survival. The median survival time was 23.5 months for patients in RPA Class I status and 10.5 months for patients in RPA Class II or III status. There was a trend (P = 0.12) toward improved median survival for patients with renal cell carcinoma (17.8 mo) as compared with patients with melanoma (9.7 mo). Multivariate analysis showed RPA class (P = 0.038) and histological diagnosis of primary tumor (P < 0.001) to be independent predictors for overall survival. In the 35 patients who underwent follow-up imaging, 9 (12%) of 73 tumors recurred locally. In 54% of the patients, distant brain failure (DBF) developed. Whole brain radiotherapy (WBRT) improved local control and decreased DBF, according to the univariate and multivariate analyses. Patients who received adjuvant WBRT in addition to SRS had 6-month actuarial local control of 100% as compared with 85% among those who did not receive WBRT (P = 0.018). Patients who received adjuvant WBRT with SRS had a 6-month actuarial DBF rate of 17%, as compared with a rate of 64% among patients who had SRS alone (P = 0.0027). CONCLUSION: Well-selected patients with brain metastases from radioresistant primary tumors who undergo SRS survive longer than historical controls. RPA Class I status and primary renal cell carcinoma predict longer survival. Adjuvant WBRT improves local control and decreases DBF but does not affect overall survival. Further studies are needed to determine which patients should receive WBRT.

Adult↗

PubMedDate not supplied

The evolving role of stereotactic radiosurgery for patients with skull base tumors.

Tumors located at the base of the skull are among the most difficult problems that neurosurgeons encounter. Management of patients with skull base tumors must take into account that complete tumor removal is not possible with acceptable morbidity in many patients. Therefore, radiation therapy and stereotactic radiosurgery are commonly performed. The use of radiosurgery for patients with skull base tumors has increased significantly over the past three decades and we now possess a better understanding of the expectations of skull base radiosurgery. For properly selected patients with benign tumors (meningiomas, schwannomas, glomus tumors), tumor control rates between 90 and 100% have been reported. Local control rates for chordomas and chondrosarcomas have ranged from 50 to 70%, but tumor growth adjacent to the treated area (marginal failure) remains a significant problem. Radiosurgery is also commonly performed for patients with malignant skull base tumors as a palliative treatment and symptom relief is common, especially for patients with facial pain related to their tumor. Follow-up beyond 10 years is still needed to better define long-term results of radiosurgery and the incidence of radiation-induced neoplasms after radiosurgery.

Humans↗