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G Loi

Publications and source records attributed to G Loi.

23 records · Page 2Linked to original sources
PubMedDate not supplied

Concurrent chemotherapy with carboplatin + 5-fluorouracil and radiotherapy in advanced squamous cell head and neck carcinoma: a retrospective single institution's study.

AIMS AND BACKGROUND: [corrected] The purpose of the study was to analyze the long-term follow-up of a single institution's experience with a regimen of concomitant carboplatin + 5-fluorouracil (CBDCA + 5-FU) infusion and radiotherapy. STUDY DESIGN: Fifty-eight patients with locally advanced squamous cell head and neck cancer treated with combined chemoradiotherapy between March 1990 and October 1998 were reviewed retrospectively. According to the TNM tumor staging, 6 patients had stage II, 21 stage III and 31 stage IV tumors. The chemotherapy regimen consisted of the combination of 5-FU and CBDCA, for a total of 3 cycles. Both drugs were given as 4-day continuous intravenous infusions during the first and fourth week of radiation therapy: 5-FU at 1000 mg/m2 per day and CBDCA at 75 mg/m2 per day. Radiation was given in single daily fractions of 1.8 to 2 Gy, to a total dose of 66 to 70 Gy. RESULTS: After the completion of chemotherapy and radiotherapy, 34 patients (58.6%) achieved clinical and radiological (computerized tomography and/or magnetic resonance imaging) complete remission, 15 patients (25.9%) partial remission >50%, 5 patients (8.6%) partial remission <50%, and 4 patients (6.8%) had no response. Toxicity was intensive but tolerable. After a median follow-up of 25 months, overall survival and recurrence-free survival estimated for the whole patient population was 52% at 3 years, and the median length of recurrence-free survival was 23 months. CONCLUSIONS: Our regimen combining standard single daily fraction radiation with the conventional dose of CBDCA and 5-FU was given without dose modification regardless of the severity of the adverse effects. It gave a clinical complete response at the primary site in 58.6% of patients. With a 52% projected 3-year overall survival, our series compares favorably with similar studies in the literature. Therefore, our results with concomitant CBDCA/5-FU infusion and radiotherapy are encouraging and suggest that CBDCA can be substituted for cisplatin with a good therapeutic index.

Adult↗
PubMedDate not supplied

How thick should CT/MR slices be to plan conformal radiotherapy? A study on the accuracy of three-dimensional volume reconstruction.

AIM AND BACKGROUND: The aim of this experimental study was to correlate the thickness of acquired CT slices (2, 4 and 8 mm) or MR slices (4 and 7 mm) with the accuracy of three-dimensional volume reconstruction as performed by a commercially available radiation therapy planning system. METHODS: We used a cylindrical phantom, with a 15-cm diameter and 20-cm height, containing 5 spheres (12.7-31.8 mm diameter) of solid Plexiglas sunk in a 3% agar jelly solution. The phantom was scanned by the CT scan with 3 different slice thicknesses (2, 4 and 8 mm and a distance of 0 mm between the slices). Two different acquisition techniques (slice thickness of 4 and 7 mm with 0.8 and 1.4 mm slice distance, respectively) were compared in the MR study. The volume values calculated from measurements were compared with the known true volume values of the spheres. RESULTS: The average percentage volume difference between calculated and true values for the smaller spheres reconstructed with CT images 2 and 4 mm thick was generally less than 8%, whereas the error for volumes reconstructed with 8-mm-thick CT slices was more than 20%. For the large spheres, the error was generally less than 5%. The data produced by MR acquisition agreed with those obtained using CT sections. CONCLUSIONS: For targets less than 1.5 cm in diameter on our system it is reasonable to acquire CT images with the smallest thickness available. For targets between 1.5 and 3 cm, it seems sufficient to acquire the localization images with a slice thickness of 4 mm. For targets more than 4 cm in diameter, considering that with our radiation therapy planning system the time spent for manual contouring and for isodose calculation highly increased with the number of acquired images, we suggest that the acquisition of CT-MR slices 8-10-mm thick is totally adequate even for conformal radiotherapy treatments.

Image Processing, Computer-Assisted↗