RÉSUMÉ
BACKGROUND: Locally advanced rectal cancer is customarily treated with neoadjuvant chemoradiotherapy (CRT) followed by a total mesorectal excision. During the course of CRT, previously non-detectable distant metastases can appear. Therefore, a restaging CT scan of the chest and abdomen was performed prior to surgery. The aim of this study was to determine the frequency of a change in treatment strategy after this restaging CT scan. METHODS: Patients treated with neoadjuvant CRT for locally advanced rectal cancer between January 2003 and July 2013 were included retrospectively. To determine the value of the restaging CT scan, the surgical treatment as planned before CRT was compared with the treatment ultimately received. RESULTS: A total of 153 patients (91 male) were eligible, and median age was 62 (32-82) years. The restaging CT scan revealed the presence of distant metastases in 19 patients (12.4, 95 % confidence interval [CI] 7.0-17.8). In 17 patients (11.1, 95 % CI 6.1-16.1), a change in treatment strategy occurred due to the detection of metastases with a restaging CT scan. CONCLUSION: A restaging CT scan after completion of neoadjuvant CRT may detect newly developed metastases and consequently alter the initial treatment strategy. This study demonstrated the added value of the restaging CT scan prior to surgery.
Sujet(s)
Tumeurs du rectum/diagnostic , Tumeurs du rectum/thérapie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Chimioradiothérapie adjuvante , Femelle , Humains , Mâle , Adulte d'âge moyen , Traitement néoadjuvant , Stadification tumorale , Tumeurs du rectum/imagerie diagnostique , Tumeurs du rectum/anatomopathologie , Rectum/chirurgie , Études rétrospectives , TomodensitométrieRÉSUMÉ
Radiotherapy is one of the corner stone treatments for patients with prostate cancer. Especially for locally advanced tumors radiotherapy +/- adjuvant androgen deprivation treatment is standard of care. This brings up the need for accurate assessment of extra prostatic tumor growth and/or the presence of nodal metastases for selection of the optimal radiation dose and treatment volume. Morphological imaging like transrectal ultra sound, computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used but are limited in their accuracy in detecting extra prostatic extension and nodal metastases. In this article we present a structured review of the literature on positron emission tomography (PET)/CT and radiotherapy in prostate cancer patients with emphasis on: 1) the pretreatment assessment of extra prostatic tumor extension, nodal and distant metastases; 2) the intraprostatic tumor characterization and radiotherapy treatment planning; and 3) treatment evaluation and the use of PET/CT in guidance of salvage treatment. PET/CT is not an appropriate imaging technique for accurate T-staging of prostate cancer prior to radiotherapy. Although macroscopic disease beyond the prostatic capsule and into the periprostatic fat or in seminal vesicle is often accurately detected, the microscopic extension of prostate cancer remains undetected. Choline PET/CT holds a great potential as a single step diagnostic procedure of lymph nodes and skeleton, which could facilitate radiotherapy treatment planning. At present the use of PET/CT for treatment planning in radiotherapy is still experimental. Choline PET based tumor delineation is not yet standardized and different segmentation-algorithms are under study. However, dose escalation using dose-painting is feasible with only limited increases of the doses to the bladder and rectum wall. PET/CT using either acetate or choline is able to detect recurrent prostate cancer after radiotherapy but stratification of patients for any local salvage treatment has not been addressed in the current literature.
Sujet(s)
Tomographie par émission de positons/méthodes , Tumeurs de la prostate/diagnostic , Tumeurs de la prostate/radiothérapie , Radiothérapie/méthodes , Tomodensitométrie/méthodes , Humains , Mâle , Métastase tumorale , Tumeurs de la prostate/anatomopathologie , Planification de radiothérapie assistée par ordinateurRÉSUMÉ
A 48-year-old woman, who had been treated for limited-disease small-cell lung cancer, presented with two white lesions in her right iris which were treated by radiotherapy and which most probably were metastases.
Sujet(s)
Carcinome à petites cellules/anatomopathologie , Tumeurs de l'iris/secondaire , Tumeurs du poumon/anatomopathologie , Carcinome à petites cellules/radiothérapie , Carcinome à petites cellules/secondaire , Femelle , Humains , Tumeurs de l'iris/diagnostic , Tumeurs de l'iris/radiothérapie , Adulte d'âge moyenRÉSUMÉ
PURPOSE: The purpose of this study was to explore regional differences in radiosensitivity of rat lung using lung function and computed tomography (CT) density as endpoints. METHODS: At first, CT scans were used to determine rat lung volumes. The data obtained enabled the design of accurate collimators to irradiate 50% of the total lung volume for the apex, base, left, right, mediastinal and lateral part of the lung. Male Wistar rats were irradiated with a single dose of 18 Gy of orthovoltage X-rays. Further rat thorax CT scans were made before and 4, 16, 26, and 52 weeks after irradiation to measure in vivo lung density changes indicative of lung damage. To evaluate overall lung function, breathing frequencies were measured biweekly starting 1 week before irradiation. RESULTS: Qualitative analysis of the CT scans showed clear density changes for all irradiated lung volumes, with the most prominent changes present in the mediastinal and left group at 26 weeks after radiation. Quantitative analysis using average density changes of whole lungs did not adequately describe the differences in radiation response between the treated groups. However, analysis of the density changes of the irradiated and non-irradiated regions of interest (ROI) more closely matched with the qualitative observations. Breathing frequencies (BF) were only increased after 50% left lung irradiation, indicating that the hypersensitivity of the mediastinal part as assessed by CT analysis, does not result in functional changes. CONCLUSIONS: For both BF and CT (best described by ROI analysis), differences in regional lung radiosensitivity were observed. The presentation of lung damage either as function loss or density changes do not necessarily coincide, meaning that for each endpoint the regional sensitivity may be different.