Interobserver variations of target volume delineation in multicatheter partial breast brachytherapy after open cavity surgery

PURPOSE To investigate interobserver variations of target volume delineations in accelerated partial breast irradiation with multicatheter brachytherapy (BT) and to assess the impact of guidelines on consistency of contouring. METHODS AND MATERIALS A contouring study with two phases in interstitial accelerated partial breast irradiation after open cavity surgery was conducted by the Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology Breast Cancer Working Group. Contours of cavity and planning target volume (PTV) on preimplant and postimplant CT images were delineated. In Phase 1, nine radiation oncologists defined the target volumes of 5 patients, whereas in Phase 2, four observers draw the contours of 4 patients applying guidelines. In Phase 1, experience in breast BT after open cavity surgery was assessed. The delineations were compared between Phase 1 and Phase 2, the impact of guidelines was assessed, and cavity visualization score was related to consistency of delineations. RESULTS Significant interobserver variability in delineations of lumpectomy cavity and PTV was observed among the participants. Observers with BT experience after open cavity surgery outlined the cavity and PTV more consistently (conformity indexgen: 0.52 vs. 0.48 and 0.59 vs. 0.55 for preimplant and postimplant cavities). For all volumes, the mean Vmax/Vmin was 2.2 vs. 2.8. Having used guidelines all conformity indices increased significantly. For cavity, the increase was 14% and 11%, whereas for the PTV, 28% and 17% on the preimplant and postimplant CT images, respectively. A strong correlation was found between consistency of contours and cavity visualization score. CONCLUSIONS Simple guidelines on defining the lumpectomy cavity significantly increased the consistency of contouring. Reliable consistency of target volume definition can be expected only for good cavity visibility.

Clinical Validation of a Peritoneal Dialysis Prescription Model in the PatientOnLine Software

Peritoneal transport characteristics and residual renal function require regular control and subsequent adjustment of the peritoneal dialysis (PD) prescription. Prescription models shall facilitate the prediction of the outcome of such adaptations for a given patient. In the present study, the prescription model implemented in the PatientOnLine software was validated in patients requiring a prescription change. This multicenter, international prospective cohort study with the aim to validate a PD prescription model included patients treated with continuous ambulatory peritoneal dialysis. Patients were examined with the peritoneal function test (PFT) to determine the outcome of their current prescription and the necessity for a prescription change. For these patients, a new prescription was modeled using the PatientOnLine software (Fresenius Medical Care, Bad Homburg, Germany). Two to four weeks after implementation of the new PD regimen, a second PFT was performed. The validation of the prescription model included 54 patients. Predicted and measured peritoneal Kt/V were 1.52 ± 0.31 and 1.66 ± 0.35, and total (peritoneal + renal) Kt/V values were 1.96 ± 0.48 and 2.06 ± 0.44, respectively. Predicted and measured peritoneal creatinine clearances were 42.9 ± 8.6 and 43.0 ± 8.8 L/1.73 m2/week and total creatinine clearances were 65.3 ± 26.0 and 63.3 ± 21.8 L/1.73 m2/week, respectively. The analysis revealed a Pearson's correlation coefficient for peritoneal Kt/V of 0.911 and Lin's concordance coefficient of 0.829. The value of both coefficients was 0.853 for peritoneal creatinine clearance. Predicted and measured daily net ultrafiltration was 0.77 ± 0.49 and 1.16 ± 0.63 L/24 h, respectively. Pearson's correlation and Lin's concordance coefficient were 0.518 and 0.402, respectively. Predicted and measured peritoneal glucose absorption was 125.8 ± 38.8 and 79.9 ± 30.7 g/24 h, respectively, and Pearson's correlation and Lin's concordance coefficient were 0.914 and 0.477, respectively. With good predictability of peritoneal Kt/V and creatinine clearance, the present model provides support for individual dialysis prescription in clinical practice. Peritoneal glucose absorption and ultrafiltration are less predictable and are likely to be influenced by additional clinical factors to be taken into consideration.

Effect of tympanic cavity evacuation and flushing on microbial isolates during total ear canal ablation with lateral bulla osteotomy in dogs.

OBJECTIVE To evaluate differences in bacterial numbers, identity, and susceptibility in samples obtained from the tympanic cavity on entry (preflush) and after evacuation and lavage (postflush) and assess perioperative and empiric antimicrobial selection in dogs that underwent total ear canal ablation (TECA) with lateral bulla osteotomy (LBO) or reoperation LBO. DESIGN Prospective clinical study. ANIMALS 34 dogs. PROCEDURE TECA with LBO or reoperation LBO was performed on 47 ears. Pre- and postflush aerobic and anaerobic samples were obtained from the tympanic cavity. Isolates and antimicrobial susceptibility patterns were compared. RESULTS Different isolates (31/44 [70%] ears) and susceptibility patterns of isolate pairs (6/44 [14%] ears) were detected in pre- and postflush samples from 84% of ears. Evacuation and lavage of the tympanic cavity decreased the number of bacterial isolates by 33%. In 26% of ears, bacteria were isolated from post-flush samples but not preflush samples. Only 26% of isolates tested were susceptible to cefazolin. At least 1 isolate from 53% of dogs that received empirically chosen antimicrobials postoperatively was resistant to the selected drugs. Anaerobic bacteria were recovered from 6 ears. CONCLUSIONS AND CLINICAL RELEVANCE Accurate microbiologic assessment of the tympanic cavity should be the basis for selection of antimicrobials in dogs undergoing TECA with LBO. Bacteria remain in the tympanic cavity after evacuation and lavage. Cefazolin was a poor choice for dogs that underwent TECA with LBO, as judged on the basis of culture and susceptibility testing results.

Comparison of ovarian cancer markers in endometriosis favours HE4 over CA125

Endometriosis is a gynaecological condition with an associated chronic inflammatory response. The ectopic growth of 'lesions', consisting of endometrial cells outside the uterine cavity, stimulates an inflammatory response initiating the activation of macrophages, and resulting in increased cytokine and growth factor concentrations in the peritoneal fluid (PF). Endometriosis‑associated inflammation is chronic and long lasting. In patients with endometriosis, the risk of developing ovarian cancer within 10 years, particularly of the endometrioid or clear cell subtype, is increased 2.5‑4 times. Endometriosis creates a peritoneal environment that exposes the affected endometriotic and the normal ovarian surface epithelial cells to agents that have been suggested to be involved in the pathogenesis of cancer. Concentrations of several cytokines and growth factors were increased in the PF of patients with endometriosis. The ovarian cancer marker, CA125, was one such growth factor; however, this remains to be confirmed. Human epididymis protein 4 (HE4) was detected at high concentrations in patients with ovarian cancer and was identified as the best biomarker for the detection of ovarian cancer. The present study determined the levels of HE4 and CA125 in the peritoneal fluid of 258 patients with and 100 control individuals without endometriosis attending the Department of Obstetrics and Gynaecology, University of Berne (Berne, Switzerland) between 2007 and 2014. The cases were subdivided into groups without hormonal treatment (n=107), or treated with combined oral contraceptives (n=45), continuous gestagens (n=56) or GnRH agonists (n=50). Both of these markers were significantly increased in the non‑treated endometriosis samples compared with the control group. Hormone treatment with either of the three agents mentioned resulted in the concentration of CA125 returning to the control levels and the concentration of HE4 decreasing to below the control levels. CA125, however not HE4, significantly differed between the proliferative and secretory cycle phases. Since HE4 is sensitive to hormonal treatment and robust towards menstrual cycle variation, HE4 is potentially superior to CA125 as an endometriosis marker and therefore has greater potential as a marker for the identification of women at risk of developing ovarian cancer.