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Kaled M Alektiar

Publications and source records attributed to Kaled M Alektiar.

23 records · Page 2Linked to original sources
PubMed2002

Adjuvant radiation for stage II-B soft tissue sarcoma of the extremity.

PURPOSE: Adjuvant radiation therapy (RT) has been shown to improve local control in patients with high-grade soft tissue sarcoma (STS) of the extremity. This study sought to define the optimal management in patients with stage II-B (high-grade, size < or = 5 cm) tumors. PATIENTS AND METHODS: Between July 1982 and December 1998, 204 adult patients with primary stage II-B STS underwent limb-sparing surgery with negative microscopic margins. Eighty-eight patients (43%) received RT; 116 (57%) did not. The RT and no-RT groups were balanced with regard to age, site (upper v lower extremity), whether patients had prior unplanned excision, and location (central, i.e., shoulder/groin v non-central). The RT group had more deep tumors (P =.03). Adjuvant RT was delivered with brachytherapy in 60% and external-beam radiation in 40% of patients. RESULTS: With a median follow-up of 67 months, the 5-year local control, distant relapse-free survival, and disease-specific survival rates were 82%, 80%, and 88%, respectively. There was no significant difference in local control between the RT and no-RT groups (84% v 80%, respectively, P =.3). Tumor depth, site, and prior unplanned excision did not correlate with local control. The only independent predictors of poor local control were central tumor location (relative risk [RR] = 3; 95% confidence interval [CI], 2 to 7; P =.005) and age more than 50 years (RR = 6; 95% CI, 2 to 13; P =.001). CONCLUSION: In this retrospective study, adjuvant RT did not significantly improve local control in patients with stage II-B STS of the extremity. The outcome of patients with central tumor location was poor, and efforts to identify the optimal local treatment approach for such patients are warranted.

Adolescent↗
PubMed2002

Predictors of survival in recurrent rectal cancer after resection and intraoperative radiotherapy.

PURPOSE: This study was designed to determine predictors of survival after surgery and intraoperative radiotherapy for recurrent rectal cancer. METHODS: From a prospective database, 634 patients undergoing resection for recurrent rectal cancer between January 1990 and June 2000 were identified. Of these, 111 received intraoperative radiotherapy with curative intent, and 100 were available for follow-up. Clinicopathologic variables from both the primary and recurrent operations were evaluated as predictors of disease-free and disease-specific survival by multivariate Cox regression and log-rank test. RESULTS: There were 54 males and 46 females, with a median age of 57 (range, 37-83) years. With a median follow-up of 23.2 months, 60 patients (60 percent) recurred: 20 (33 percent) locally, 27 (45 percent) distantly, and 13 (22 percent) at both sites. Of all variables analyzed, only complete resection with microscopically negative margins and the absence of vascular invasion in the recurrent specimen predicted improved disease-free and disease-specific survival (P < 0.01 for all). Median disease-free survival and median disease-specific survival were 31.2 and 66.1 months, respectively, for complete resection compared with 7.9 and 22.8 months for resection with microscopic or grossly positive margins (P < 0.01 for both). Median disease-free survival and median disease-specific survival were 6.4 and 16.1 months, respectively, in the presence of vascular invasion in the recurrent specimen compared with 23.3 and 57.3 months in the absence of vascular invasion (P < 0.01 and P < 0.05, respectively). Complete resection and the absence of vascular invasion were the only predictors of improved local control as well (P < 0.05 and P < 0.01, respectively). CONCLUSION: Resection with negative microscopic margins and absence of vascular invasion are independent predictors of local control and improved survival after resection and intraoperative radiotherapy for recurrent rectal cancer.

Adult↗
PubMedDate not supplied

Intensity-modulated radiotherapy.

Intensity-modulated radiotherapy represents a recent advancement in conformal radiotherapy. It employs specialized computer-driven technology to generate dose distributions that conform to tumor targets with extremely high precision. Treatment planning is based on inverse planning algorithms and iterative computer-driven optimization to generate treatment fields with varying intensities across the beam section. Combinations of intensity-modulated fields produce custom-tailored conformal dose distributions around the tumor, with steep dose gradients at the transition to adjacent normal tissues. Thus far, data have demonstrated improved precision of tumor targeting in carcinomas of the prostate, head and neck, thyroid, breast, and lung, as well as in gynecologic, brain, and paraspinal tumors and soft tissue sarcomas. In prostate cancer, intensity-modulated radiotherapy has resulted in reduced rectal toxicity and has permitted tumor dose escalation to previously unattainable levels. This experience indicates that intensity-modulated radiotherapy represents a significant advancement in the ability to deliver the high radiation doses that appear to be required to improve the local cure of several types of tumors. The integration of new methods of biologically based imaging into treatment planning is being explored to identify tumor foci with phenotypic expressions of radiation resistance, which would likely require high-dose treatments. Intensity-modulated radiotherapy provides an approach for differential dose painting to selectively increase the dose to specific tumor-bearing regions. The implementation of biologic evaluation of tumor sensitivity, in addition to methods that improve target delineation and dose delivery, represents a new dimension in intensity-modulated radiotherapy research.

Abdominal Neoplasms↗
PubMedDate not supplied

Adjuvant brachytherapy for primary high-grade soft tissue sarcoma of the extremity.

BACKGROUND: We reviewed single-institution experience using brachytherapy alone for primary high-grade soft tissue sarcoma of the extremity. METHODS: Between July 1982 and September 1997, 202 adult patients with primary high-grade soft tissue sarcoma of the extremity were treated with limb-sparing surgery and adjuvant brachytherapy. All patients underwent complete gross resection, but the margin of resection was microscopically positive in 18% of patients. The median dose of brachytherapy was 45 Gy delivered over 5 days. Tumors located in the shoulder or groin were defined as central location. Complications were assessed in terms of wound complications, bone fracture, and peripheral nerve damage. RESULTS: With a median follow-up of 61 months, the 5-year local control, distant relapse-free survival, and overall survival rates were 84%, 63%, and 70%, respectively. On multivariate analysis, poor local control correlated with shoulder location, positive microscopic margins of resection, and nonshoulder upper extremity site. The 5-year actuarial rates of wound complications requiring reoperation, bone fracture, and grade > or = 3 nerve damage were 12%, 3%, and 5%, respectively. CONCLUSIONS: Adjuvant brachytherapy provides adequate local control and acceptable morbidity that compares favorably with data reported for external beam radiation. Shoulder tumor location was identified as an independent prognostic factor for poor local control, mandating further improvement in the local management of these tumors.

Adolescent↗