Biomedical subjects

Maria Antonietta Gambacorta

Publications and source records attributed to Maria Antonietta Gambacorta.

10 recordsLinked to original sources

PubMed2006

Long-term results after neoadjuvant radiochemotherapy for locally advanced resectable extraperitoneal rectal cancer.

PURPOSE: This study was designed to evaluate long-term outcome in locally advanced resectable extraperitoneal rectal cancer treated by preoperative radiochemotherapy. METHODS: Eighty-three consecutive patients who developed locally advanced resectable extraperitoneal rectal cancer underwent preoperative concomitant radiochemotherapy followed by surgery, including total mesorectal excision. RESULTS: Median follow-up was 108 (range, 10-169) months. The living patients underwent complete follow-up of, at least, nine years. Fourteen patients developed local recurrence. The time to detection was longer than two years in eight cases and longer than five years in four. Twenty-one patients developed metastases, 19 within the first five years from surgery. At the univariate analysis, clinical stage at presentation, lymph node involvement at clinical restaging after neoadjuvant therapy, and pT and pN stage were found positively correlated to the incidence of metastases. At the multivariate analysis, the only factors which confirmed a positive correlation were pT stage and pN stage. The actuarial overall survival at five, seven, and ten years was 75.5, 67.8, and 60.4 percent, respectively. The same figures for cancer-related survival were 77.9, 70, and 65.8 percent. At the univariate analysis, factors directly correlated with worse survival were: TNM stage at clinical restaging after neoadjuvant therapy (in particular lymph node involvement) pTNM, pT, and pN. At the multivariate analysis the only factors that confirmed a correlation with worse survival were pTNM, pT, and pN. CONCLUSIONS: Long- term follow-up allows to individuate 28 percent of all local relapses after the first five years from surgery. Postoperative stage is highly predictive of prognosis.

Adult↗

PubMed2006

In vivo dosimetry by an aSi-based EPID.

A method for the in vivo determination of the isocenter dose, Diso, and mid-plane dose, Dm, using the transmitted signal St measured by 25 central pixels of an aSi-based EPID is here reported. The method has been applied to check the conformal radiotherapy of pelvic tumors and supplies accurate in vivo dosimetry avoiding many of the disadvantages associated with the use of two diode detectors (at the entrance and exit of the patient) as their periodic recalibration and their positioning. Irradiating water-equivalent phantoms of different thicknesses, a set of correlation functions F(w, l) were obtained by the ratio between St and Dm as a function of the phantom thickness, w, for a different field width, l. For the in vivo determination of Diso and Dm values, the water-equivalent thickness of the patients (along the beam central axis) was evaluated by means of the treatment planning system that uses CT scans calibrated in terms of the electron densities. The Diso and Dm values experimentally determined were compared with the stated doses D(iso,TPS) and D(m,TPS), determined by the treatment planning system for ten pelvic treatments. In particular, for each treatment four fields were checked in six fractions. In these conditions the agreement between the in vivo dosimetry and stated doses at the isocenter point were within 3%. Comparing the 480 dose values obtained in this work with those obtained for 30 patients tested with a similar method, which made use of a small ion-chamber positioned on the EPIDs to obtain the transmitted signal, a similar agreement was observed. The method here proposed is very practical and can be applied in every treatment fraction, supplying useful information about eventual patient dose variations due to the incorrect application of the quality assurance program based on the check of patient setup, machine setting, and calculations.

Humans↗

PubMed2005

Tumor vascularity evaluated by transrectal color Doppler US in predicting therapy outcome for low-lying rectal cancer.

PURPOSE: To evaluate the impact on T downstaging of the vasculature supplying blood flow to rectal cancer evaluated by color Doppler ultrasound. METHODS AND MATERIALS: Color Doppler images were graded in 29 T3-staged rectal carcinoma patients sonographically just before chemoradiation. Any arterial vessels detected in rectal masses were assigned one of two grades: vascularity was considered as grade 1 for vessels feeding the periphery and as grade 2 for vessels coursing in all rectal masses within its peripheral and central portions. The pulsatility indices (PI = peak systolic velocity - end-diastolic velocity/time-averaged maximum velocity) were calculated in the central and peripheral portions. RESULTS: The pathologic observations showed a change in stage in 15 of the 23 patients graded 2, positive predictive value 65.2% (p = 0.047), and in one of the six rectal cancers graded 1 (negative predictive value, 83.3%). The minimal peripheral PI values in rectal cancer graded 2 were higher in nonresponding (2.2 +/- 1.3) than in responding lesions (1.6 +/- 0.7) p = 0.01. CONCLUSION: Vascularity graded 2 associated with low peripheral PI values are indicators of therapy outcome. Vascularity graded 1 and high peripheral PI values in graded 2 have negative predictive value.

Adenocarcinoma↗

PubMed2005

The relationship of pathologic tumor regression grade (TRG) and outcomes after preoperative therapy in rectal cancer.

PURPOSE: To examine the relationship between tumor regression grade (TRG) and outcomes in patients with rectal cancer treated with preoperative therapy. METHODS AND MATERIALS: Specimens from 144 patients with cT3,4 rectal cancer who had received preoperative radiation +/- chemotherapy and had a minimum follow-up of 3 years were retrospectively reviewed. TRG, which involves examining the residual neoplastic cells and scoring the degree of both cytological changes, including nuclear pyknosis or necrosis and/or eosinophilia, as well as stromal changes, including fibrosis (either dense or edematous) with or without inflammatory infiltrate and giant-cell granulomatosis around ghost cells and keratin, was quantified in five grades according to the Mandard score (Cancer 1994;73:2680-2686). The greater the response, the lower the TRG score. The median follow-up was 72 months (range, 40-143 months). RESULTS: Of the 144 patients, 19% were TRG1, 12% were TRG2, 21% were TRG3, 46% were TRG4, and 1% were TRG5. To simplify the analysis, TRG was combined into two groups: TRG1-2 and TRG3-5. By univariate analysis, none of the pretreatment factors examined, including age, circumference, length, distance from the anorectal ring, pretreatment T and N stage, and INDpre (defined as the pretreatment reference index size based on digital rectal examination), had an impact on 5-year outcomes, including local control, metastases-free survival, disease-free survival, and overall survival. Postoperative parameters, including pathologic T stage (pT), pathologic N stage (pN), and TRG, did significantly influence 5-year outcomes. These included local failure: pT0-2: 5% vs. pT3-4: 19%, p = 0.007; pN0: 7% vs. pN1-3: 26%, p = 0.002; TRG1-2: 2% vs. TRG3-5: 17%, p = 0.013; metastasis-free survival: pT0-2: 86% vs. pT3-4: 62%, p = 0.005; pN-: 86% vs. pN*: 42%, p < 0.001; TRG1-2: 91% vs. TRG3-5: 66%, p = 0.004; disease-free survival: pT0-2: 83% vs. pT3-4: 54%, p = 0.001; pN0: 80% vs. pN1-3: 39%, p < 0.001; TRG1-2: 91% vs. TRG3-5: 58%, p < 0.001; and overall survival: pT0-2: 85% vs. pT3-4: 65%, p = 0.007; pN0: 86% vs. pN1-3: 45%, p < 0.001; TRG1-2: 89% vs. TRG3-5: 68%, p = 0.004. By multivariate analysis combining all pre- and posttreatment parameters, only pN (p < 0.001) and TRG (p = 0.005) significantly predicted disease-free survival. Furthermore, TRG predicted the incidence of pathologic nodal involvement (p < 0.0001). CONCLUSIONS: By univariate analysis, TRG is a predictor for local failure, metastases-free survival, and overall survival. By multivariate analysis, it predicts improved disease-free survival. Given the ability of TRG to predict those patients with N* disease, it may be helpful, in combination with other clinicopathologic factors, in selecting patients for a more conservative procedure, such as local excision rather than radical surgery, after preoperative therapy.

Adult↗

PubMed2004

Chemoradiation with raltitrexed and oxaliplatin in preoperative treatment of stage II-III resectable rectal cancer: Phase I and II studies.

PURPOSE: Two separate studies were conducted, the first to evaluate the maximal tolerated dose and the second the efficacy of raltitrexed plus oxaliplatin in conjunction with preoperative chemoradiation in patients with resectable T3 rectal carcinoma. METHODS AND MATERIALS: A total of 48 patients received radiotherapy (50 Gy) administered to the posterior pelvis 5 d/wk for 5 weeks. Combination raltitrexed (3 mg/m(2)) and oxaliplatin (60 to 130 mg/m(2)) was administered on Days 1, 19, and 38. RESULTS: The recommended dose of oxaliplatin is 130 mg/m(2) (maximal tolerated dose not reached). No patients developed Grade 4 acute toxicity. Grade 3 acute toxicity occurred in 9 patients (18.7%). It was hematologic in 1 patient and GI in 1 patient; 7 patients had an asymptomatic increase of transaminase. Surgery was performed in 47 (98%) of 48 patients. Of the 47 patients, 42 underwent sphincter-saving surgery; in 19, the tumor at diagnosis was located <30 mm from the anorectal ring. Chemoradiation in combination with raltitrexed and oxaliplatin produced high rates of tumor response. The overall tumor downstaging rate was 73% for T and N stages. A complete pathologic tumor response (pT0) or microscopic tumor foci (pTmic) was observed in 28 patients. The tumor regression grade (TRG), using the Mandard scoring system, was TRG1 in 16 patients (43.2%), TRG2 in 12 (32.4%), TRG3 in 12 (32.4%), TRG4 in 6 (16.2%), and TRG5 in 1 patient (2.7%). CONCLUSION: Raltitrexed plus oxaliplatin combined with pelvic radiotherapy was effective and well tolerated in patients with resectable T3 rectal carcinoma.

Aged↗

PubMed2004

Chemoradiation with raltitrexed (Tomudex) in preoperative treatment of stage II-III resectable rectal cancer: a phase II study.

PURPOSE: To evaluate the impact of preoperative chemoradiation with raltitrexed (Tomudex(1)) on tumor response, sphincter preservation, and toxicity in patients with locally advanced rectal cancer. METHODS AND MATERIALS: Between 1998 and 2002, 54 consecutive patients with Stage T3 or T2N+ resectable rectal carcinoma were treated with preoperative chemoradiation, i.v. bolus of raltitrexed on Days 1, 19, and 38 and concurrent 50 Gy external beam radiotherapy. Surgery was performed 6-8 weeks after the end of chemoradiation. RESULTS: No patients had Grade 4 acute toxicity. Grade 3 acute toxicity occurred in 16.6% of cases and was hematologic in 6 patients and GI in 2. The overall clinical response rate was 88.8%, with a complete response in 5.5%, partial response in 83.3%, and no change in 9.2%. No patient showed disease progression. All patients underwent surgery. Sphincter saving was obtained in 83.3% of patients. No perioperative mortality occurred, and the perioperative morbidity rate was 5.5%. Of 20 resected patients (37%) who were candidates for abdominoperineal resection at diagnosis (anorectal ring distance < or =30 mm), 13 (65%) underwent a sphincter-saving procedure. At pathologic examination, 13 (24%) of 54 patients had a complete pathologic response (pT0) and 10 (18.5%) had rare isolated residual cancer cells (pT, microscopic foci). Overall, 42.5% had major downstaging. The tumor regression grade (TRG), using Mandard's score system, was also applied and was TRG1 in 13 patients, TRG2 in 11, TRG3 in 20, and TRG4 in 10 patients; no patient had TRG5. CONCLUSION: The use of raltitrexed in a neoadjuvant chemoradiation schedule promoted high pathologic tumor downstaging and use of a sphincter-saving procedure. The low toxicity profile supports the rationale to explore raltitrexed combined with other drugs with different biologic targets.

Aged↗

PubMed2004

Preoperative radiotherapy combined with intraoperative radiotherapy improve results of total mesorectal excision in patients with T3 rectal cancer.

PURPOSE: The survival advantage of preoperative radiotherapy in patients with rectal cancer is still a matter of debate, because its incremental benefit in the total mesorectal excision setting is unclear. This study was designed to evaluate early and long-term results of preoperative radiotherapy plus intraoperative radiotherapy in a homogeneous population of T3 middle and lower rectal cancer patients submitted to total mesorectal excision. METHODS: A series of 113 patients with middle and lower T3 rectal cancer consecutively submitted to total mesorectal excision at a single surgical unit from 1991 to 1997 were divided into two groups according to type of neoadjuvant treatment: preoperative radiotherapy (38 Gy) plus intraoperative radiotherapy (10 Gy; n = 69), and no preoperative treatment (total mesorectal excision; n = 44). Standard statistical analyses were used to evaluate early (downstaging, intraoperative factors, hospital morbidity, and mortality rates) and long-term results (recurrence and survival). RESULTS: Overall, 68.2 percent of patients were downstaged by the preoperative regimens (T0 specimens in 3 cases). Postoperative complications were comparable in the two groups. Five-year, disease-specific survival was 81.4 and 58.1 percent in preoperative radiotherapy plus intraoperative radiotherapy group and total mesorectal excision group, respectively (P = 0.052). Corresponding figures for disease-free survival were 73.1 and 57.2 percent in the two groups, respectively (P = 0.096). The rates of local recurrence at five years were 6.6 and 23.2 percent in preoperative radiotherapy plus intraoperative radiotherapy and total mesorectal excision groups, respectively (P = 0.017). CONCLUSIONS: Preoperative radiotherapy plus intraoperative radiotherapy associated with total mesorectal excision reduce local recurrence rate and improve survival in T3 rectal cancer compared with total mesorectal excision alone.

Adult↗

PubMedDate not supplied

Biological factors and therapeutic modulation in rectal cancer radiotherapy.

Rectal cancer includes a wide range of diseases that require personalized treatments for optimization of results. Colorectal cancer is one of the best characterized for the genetic events underlying the development of malignancy. Most colorectal carcinomas develop from benign preneoplastic lesions; progression from benign adenoma to malignant carcinoma advances throughout a series of well defined histological stages of the adenoma-carcinoma sequence. The etiology of colorectal cancer is multifactorial with the participation of environmental factors, genetic susceptibility and somatic mutations during onset and progression. Molecular parameters of specific tumors can be predictive of therapeutic outcome or prognostic of the individual natural history. Main biological factors and their mechanisms of action in terms of response to therapies and late outcome, are illustrated.

Biological Factors↗

PubMedDate not supplied

Virtual simulation: fifteen years later.

In the last two decades there was a radical change in radiotherapy setup. The growing availability of CT equipment and console for computer-aided treatment planning setup enabled the use of advanced technologies as conformal 3D radiation therapy in most centers. In particular in 1987 virtual simulation was proposed for setup. During its use a number of application modalities appeared. Virtual simulation in some centers is applied alone while in others it is associated with conventional simulation. However, from numerous reports published in last years it seems that virtual simulation significantly improves treatment quality independently of radical or palliative intent and of the size of treated volumes (high doses to small volumes or wide shaped fields). Some studies stressed that virtual simulation could significantly shorten treatment planning times with consequent cost reduction. The use of virtual simulation evidenced associated problems and in particular setup limitations due to the CT gantry size, the need to up-date the conventional modalities of setup verification according to the new technologies and more generally to up-date quality assurance procedures in an advanced technological setting. Finally there was the self-evident need of a better knowledge of the anatomy on axial sections, of tumor spread routes in particular.

Computer Simulation↗

PubMedDate not supplied

Preoperative radiotherapy in gastric cancer: CTV definition for conformal therapy according to tumor location.

In the past radiation oncologists had not a major interest in the treatment of gastric cancer, but the positive outcomes of the Intergroup Study (INT-0116) supported the role of locoregional control in promoting better survival. To reduce the toxicity and the risk of residual disease in locally advanced tumors after surgery,a preoperative approach was tentatively considered. The aim of this manuscript is to define the location of nodal area at risk for cancer involvement according to the tumor location (cardias, corpus, antrum) on CT images to help the radiotherapist in the contouring process of the CTV for preoperative conformal treatment of gastric cancer. The analysis of both the percentage of nodal involvement detected at surgery and of the site of recurrence after radical surgery can direct to the areas to be considered at risk with its contouring on CT. Preoperative conformal-three dimensional radiotherapy of gastric cancer requires clear and well defined contouring guide-lines to allow the evaluation of clinical outcomes and the analysis if the area at risk for recurrence has changed after the preoperative approach.

Combined Modality Therapy↗