Interobserver variability in clinical target volume delineation for primary mediastinal B-cell lymphoma.

PURPOSE: The purpose of this study was to evaluate interobserver variability among radiation oncologists with experience in the field of lymphoma radiation therapy in the delineation of clinical target volume (CTV) in a challenging case of primary mediastinal B-cell lymphoma. METHODS AND MATERIALS: Ten experienced radiation oncologists were invited to a 1-day contouring session. The case of a 56-year-old man with primary mediastinal B-cell lymphoma with complete metabolic response after chemotherapy was chosen as the sample for the study. A brief presentation of his clinical history was given, together with guidelines for contouring. The 10 CTVs obtained were then compared in terms of variation in total volume and in craniocaudal, laterolateral, and anteroposterior diameters. The CTV with the best Dice similarity coefficient (DSC) between the union of all 10 CTVs and the individual CTV was considered the reference CTV, and the DSC and the Hausdorff distance (HD) for each volume compared with the reference CTV were then calculated. RESULTS: A significant variability was found in total volume (mean, 498.3 cm(3); range, 181.8-1003 cm(3)) and craniocaudal (median, 144.7 mm; range, 80.6-159 mm), laterolateral (median, 133.5 mm; range, 83.7-149.5 mm), and anteroposterior diameters (median, 136.2 mm; range, 84-150.5 mm). Analysis of the DSC and the HD showed a mean DSC of 0.53 (range, 0.31-0.74) and a mean HD of 6.4 cm (range, 1.8-14.8 cm). CONCLUSIONS: Results of this study strongly indicate the need to develop and share appropriate contouring guidelines among experts and suggest the promotion of specific educational activities to improve radiation therapy quality in both clinical trials and routine clinical practice.

Contouring of the Pharyngeal Superior Constrictor Muscle (PSCM). A cooperative study of the Italian Association of Radiation Oncology (AIRO) Head and Neck Group.

BACKGROUND AND PURPOSE: Irradiation of the Pharyngeal Superior Constrictor Muscle (PSCM) seems to play a crucial role in radiation-related swallowing dysfunctions. Purpose of our study was to quantify operator-related variability in the contouring of PSCM on Computed Tomography (CT) scans and adherence with contours derived from MR images. MATERIALS AND METHODS: Three sets of treatment planning CT and their corresponding MR images were selected. Contouring of the PSCM was performed using both a literature-based method, derived from literature review, and an optimized method, derived from Magnetic Resonance (MR) images thus obtaining "literature-based" and "optimized" contours. Each operator contoured the PSCM on CT scans according to both methods for three times in three different days. Inter- and intra-operator variability and adherence to a contour obtained from MR images (named "MR-derived" contour) were analyzed. RESULTS: Thirty-four operators participated and 612 contours were obtained. Both intra- and inter-operator variability and adherence to the "MR-derived" contour were significantly different between the two methods (p⩽0.05). The "optimized" method showed a lower intra- and inter-operator variability and a higher adherence to the "MR-derived" contour. CONCLUSIONS: The "optimized" method ameliorates both operator-related variability and adherence with MR images.

Predictive factors for oropharyngeal mycosis during radiochemotherapy for head and neck carcinoma and consequences on treatment duration. Results of mycosis in radiotherapy (MIR): a prospective longitudinal study.

BACKGROUND AND PURPOSE: Oropharyngeal mycosis (OPM) is a complication of radiotherapy (RT) treatments for head and neck (H&N) cancer, worsening mucositis and dysphagia, causing treatment interruptions and increasing overall treatment time. Prophylaxis with antifungals is expensive. Better patient selection through the analysis of prognostic factors should improve treatment efficacy and reduce costs. MATERIALS AND METHODS: A multicentre, prospective, controlled longitudinal study, with ethics committee approval, examined H&N cancer patients who were candidates for curative treatments with radio-chemotherapy. Patients were divided in groups according to OPM appearance: before the starting of RT (cases), during RT (new cases) and never (no cases). RESULTS: Of 410 evaluable patients, 20 were existing cases, 201 new cases and 189 did not report OPM. In our study OPM appears in 42.4% of people >70years and in 58.2% of younger individuals (p=0.0042), and in 68.6% of women versus 50.8% of men (p=0.0069). Mucositis and dysphagia were higher and salivation reduced among people with OPM (p<0.0000). Patients with OPM had longer hospitalization (p=0.0002) and longer (>12days) treatment interruptions (p=0.0288). CONCLUSIONS: Patients with OPM had higher toxicity and a greater number of long treatment interruptions. Analyses of prognostic factors can help clinicians understand OPM distribution and select patients with the highest probability of OPM for antifungal prophylaxis.

Role of radiotherapy in patients with early-stage diffuse large B-cell lymphoma of Waldeyer's ring in remission after anthracycline-containing chemotherapy.

Consolidation radiotherapy (cRT) in patients with stage I/II diffuse large B-cell lymphoma of the Waldeyer's ring (WR-DLBCL) in complete remission (CR) after induction chemotherapy (CHT) is often associated with relevant acute and chronic toxicity, and its impact on survival remains to be defined. A total of 184 patients in CR after anthracycline-based chemotherapy were retrospectively analyzed: 62 underwent CHT alone (CHT group), while 122 (66%) patients were referred to cRT (CHT + RT group). After a median follow-up of 54 months, 36 patients (20%) experienced relapse: 19% in the CHT group and 20% in the CHT + RT group. At the time of analysis 47 (76%) CHT patients and 97 (80%) CHT + RT patients were alive. Five-year overall survival (OS), disease-free survival (DFS) and lymphoma-specific survival (LSS) were 80%, 74% and 86%, respectively. Five-year OS was significantly prolonged in the CHT + RT group, while DFS and LSS were similar between groups. This discrepancy was attributed to a high percentage of deaths due to unrelated causes in CHT patients. cRT does not prolong LSS in patients with early-stage WR-DLBCL in CR after anthracycline-containing chemotherapy. An international confirmatory trial is warranted.

High response rate and improvement of long-term survival with combined treatment modalities in patients with poor-risk primary thyroid diffuse large B-cell lymphoma: an International Extranodal Lymphoma Study Group and Intergruppo Italiano Linfomi study.

The impact of different treatment modalities and prognostic factors on the clinical course of primary thyroid diffuse large B-cell lymphoma (PTDLBCL) is still the subject of research. This study was conducted to clarify these clinical aspects of this disorder. The clinical parameters of 48 patients with PTDLBCL at time of diagnosis were comparable to those of previous studies. Patients underwent either radiotherapy (RT)  ±  surgery (SX), chemotherapy (CHT) alone or in combination with local treatments (RT or SX), or SX followed by CHT and RT. A 90% complete remission (CR) rate was observed among patients who underwent combined treatment modalities (CTM), compared to 76% among the others. The 5-year progression-free survival differed significantly between both groups (p = 0.028). Poor performance status and advanced age correlated with decreased survival. PTDLBCL is a curable disease prevalent in elderly patients. Combined treatment modalities were able to induce an elevated rate of CR, improving long-term survival in younger patients. However, the outcome in elderly patients still remains unsatisfactory.

CLIPI: a new prognostic index for indolent cutaneous B cell lymphoma proposed by the International Extranodal Lymphoma Study Group (IELSG 11).

Indolent primary cutaneous B cell lymphomas (PCBCL) generally have a good prognosis, but they often relapse leading in some cases to extracutaneous disease and therefore, to poor survival. We developed a prognostic model to improve the therapeutic approach to these lymphomas. Two hundred and seventeen patients with diagnosis of indolent PCBCL stage IE or IIE were assessed retrospectively. The prognostic model was built to fit a Cox proportional hazard model using all the covariates affecting progression-free survival (PFS) at p<0.1 in the univariate analysis, and the final model was selected based on the Bayes Information Criteria. Elevated serum lactate dehydrogenase, morphology of the lesion (nodule vs. other), and >2 lesions were independent predictors for PFS. To each prognostic factor was assigned a value of 1. Patients were then stratified to three risk groups: score 0 (28%), low risk; score 1 (55%), intermediate risk; score 2 and 3 (17%), high risk with a 5-year PFS of 91%, 64%, and 48%, respectively (p<0.001). The CLIPI is an easily applicable prognostic index and represents a promising tool for risk-adapted treatment strategies. However, it needs to be addressed in prospective clinical studies.

A consensus protocol: Image-improved therapeutic guidelines for limited adult Hodgkin's disease.

Hodgkin's disease (HD) has greatly benefited from new technologies in terms of less invasive and more accurate staging as well as improved overall and relapse-free survival. However, the likelihood of late adverse effects of treatment, including second tumors, has increased due to the longer survival of patients with HD. Today's trend is to aim at minimal therapeutic exposure while guaranteeing lower therapy-related morbidity. This encourages new research efforts but also leads to less uniformity in treatments, as observed in the Veneto Region in Italy. The Gruppo Veneto Linfomi, composed of representatives of Radiotherapy and Oncology Departments of the Veneto Region, has been analyzing this problem and proposing therapy guidelines since 1995. A set of 10 prognostic factors has been developed to identify three prognostic groups: highly favorable (HF) are patients up to 40 years of age presenting with stage I disease involving only one site of disease with a maximum tumor diameter (TD) of 5 cm and no adverse factors. In this group only mantle field irradiation is recommended if the disease is located in the neck or above, inverted-Y irradiation is recommended for distal subdiaphragmatic lesions, and subtotal nodal irradiation in all other cases. HF cases may also be treated like favorable cases with limited chemoradiation. Favorable (F) cases are patients in stage I with a TD greater than 5 cm and smaller than 10 cm or stage II, up to three sites of disease and negative prognostic factors for systemic disease. All other patients are included in the "not favorable" (NF) group at Ann Arbor stage I or II with any adverse prognostic factor. For the latter two groups, chemotherapy with the ABVD or Stanford V regimen precedes involved-field radiotherapy to sites with a TD of at least 5 cm. The total irradiation dose is determined by local disease extent and level of response to chemotherapy. Images on which the radiation fields are drawn serve as an important reference to improve the homogeneity of treatments. This protocol includes a list of adverse treatment effects (chemo- and/or radiotherapy) together with follow-up guidelines for the early detection of secondary cancers in previously irradiated patients.