Materials Science Toolkit for Carbon Footprint Assessment: A Case Study for Endoscopic Accessories of Common Use

Ironically, healthcare systems are key agents in respiratory-related diseases and estimated deaths because of the high impact of their greenhouse gas emissions, along with industry, transportation, and housing. Based on safety requirements, hospitals and related services use an extensive number of consumables, most of which end up incinerated at the end of their life cycle. A thorough assessment of the carbon footprint of such devices typically requires knowing precise information about the manufacturing process, which is rarely available in detail because of the many materials, pieces, and steps involved during the fabrication. Yet, the tools most often used for determining the environmental impact of consumer goods require a bunch of parameters, mainly based on the material composition of the device. Here, we report a basic set of analytical methods that provide the information required by the software OpenLCA to calculate the main outcome related to environmental impact, greenhouse gas emissions. Through thermogravimetry, calorimetry, infrared spectroscopy, and elemental analysis, we proved that obtaining relevant data for the calculator in the exemplifying case of endoscopy tooling or accessories is possible. This routine procedure opens the door to a broader, more accurate analysis of the environmental impact of everyday work at hospital services, offering potential alternatives to minimize it.

From flood paths to floodways, an efficient method to map, identify and evaluate suitable floodways: A case study from Trondheim, Norway

Due to climate change and rapid urbanisation, many Norwegian cities and urban areas suffer from pluvial flooding caused by intense rainfall exceeding the capacity of the stormwater management system. This results in increased runoff rates, volumes and peak flows in the drainage network. In response to these challenges, the authors explore the potential of utilising the urban surface's ability to transport floodwater as an integral component of the stormwater infrastructure. When the capacity of the stormwater drainage system is exceeded, the overland flow paths transporting floodwater are considered a part of the stormwater management system, as floodways. The study proposes a spatial GIS method to map existing drainage lines and identify existing surface areas that function as floodways, combined with an automated process to identify which drainage lines could be implemented as stormwater management measures. Critical points are introduced to assess the floodways' potential hazards, combined with a classification method to evaluate and sort floodways. A case study from Trondheim, Norway, was used to demonstrate how drainage lines can be identified as floodways using the proposed method. The case study is also used to illustrate how a GIS-based analysis can be extended from identifying to evaluating floodways and whether GIS is sufficient for floodway evaluation. The method enables urban planners and municipalities to identify which areas of the urban surface already function as floodways during extreme events, and to prioritise measures to secure such areas and increase the city's flood resilience. The results highlight the need to assess existing areas that function as floodways, and to implement and design needed areas as floodways. GIS-based methods combined with an evaluation scheme can be an adequate tool to map and evaluate floodways in urban areas. When using GIS-based methods, however, the corresponding hazard potential, and also the uncertainty of the floodway's spatial placement, should be considered.

Endoscopic treatment (endoscopic balloon dilation/self-expandable metal stent) vs surgical resection for the treatment of de novo stenosis in Crohn's disease (ENDOCIR study): an open-label, multicentre, randomized trial

BACKGROUND

Stenosis is one of the most common complications in patients with Crohn's disease (CD). Endoscopic balloon dilation (EBD) is the treatment of choice for a short stenosis adjacent to the anastomosis from previous surgery. Self-expandable metal stents (SEMS) may be a suitable treatment option for longer stenoses. To date, however, there is no scientific evidence as to whether endoscopic (EBD/SEMS) or surgical treatment is the best approach for de novo or primary stenoses that are less than 10 cm in length.

METHODS/DESIGN

Exploratory study as "proof-of-concept", multicentre, open-label, randomized trial of the treatment of de novo stenosis in the CD; endoscopic treatment (EBD/SEMS) vs surgical resection (SR). The type of endoscopic treatment will initially be with EDB; if a therapeutic failure occurs, then a SEMS will be placed. We estimate 2 years of recruitment and 1 year of follow-up for the assessment of quality of life, costs, complications, and clinical recurrence. After the end of the study, patients will be followed up for 3 years to re-evaluate the variables over the long term. Forty patients with de novo stenosis in CD will be recruited from 15 hospitals in Spain and will be randomly assigned to the endoscopic or surgical treatment groups. The primary aim will be the evaluation of the patient quality of life at 1 year follow-up (% of patients with an increase of 30 points in the 32-item Inflammatory Bowel Disease Questionnaire (IBDQ-32). The secondary aim will be evaluation of the clinical recurrence rate, complications, and costs of both treatments at 1-year follow-up.

DISCUSSION

The ENDOCIR trial has been designed to determine whether an endoscopic or surgical approach is therapeutically superior in the treatment of de novo stenosis in CD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04330846. Registered on 1 April 1 2020. https://clinicaltrials.gov/ct2/home.

Revising green roof design methods with downscaling model of rainfall time series

Historically, green infrastructure for stormwater management has been event-based designed. This study aims to realign the green infrastructure design strategies with principles for robust decision making, through the example of green roofs design with the variational method and exemplified using the Norwegian context of the 3-step approach (3SA) for stormwater management. The 3SA consists of planning solutions to handle day-to-day rain at site scale through infiltration (step 1) and detention (step 2), and extreme events with safe floodways (step 3). An innovative framework based on downscaling of rainfall timeseries is suggested as follows: (i) long duration continuous simulation for retention variation and day-to-day discharge, corresponding to step 1 in the 3SA; (ii) intensive sampling of local extreme events to estimate reliability and robustness of solutions, corresponding to steps 2 and 3 in the 3SA. Comparing the traditional variational method to Highly-Informed-Design-Evaluation-Strategy (HIDES), it was found that the variational method possibly leads to incorrect decisions while the suggested novel approach was found to give more informed and reliable results by suggesting a design based on both operating mode and failure mode. It allows to embed solutions within the urban water system by facilitating the link between the steps of the 3SA. Such a framework was found to be data-wise applicable in the Norwegian context.

Quality of life during one year of postoperative prophylactic drug therapy after intestinal resection in Crohn's patients: Results of the APPRECIA trial

BACKGROUND

In APPRECIA trial, Crohn's disease (CD) patients undergoing intestinal resection were randomized to postoperative adalimumab (ADA) or azathioprine (AZA).

AIMS

To evaluate health-related quality of life (HRQoL) in APPRECIA trial.

METHODS

HRQoL was evaluated using disease-specific shortened Spanish version of the IBDQ (SIBDQ-9) and generic European Quality of Life-5 Dimensions (EQ-5D) questionnaires, completed at baseline and at weeks 24 and 52.

RESULTS

Sixty-one patients (37 ADA and 24 AZA) had evaluable data for HRQoL. Patients treated with ADA or AZA had significant improvement from baseline to weeks 24 and 52 in SIBDQ-9 and EQ-5D (p < 0.001 and p ≤ 0.006 for all comparisons, respectively). There were no differences between treatment arms in mean change in SIBDQ-9 and EQ-5D at weeks 24 and 52 vs baseline. Only patients without endoscopic recurrence had significant improvement in SIBDQ-9 (p < 0.001) and EQ-5D (p < 0.001) at week 52. At week 52, there was a high to moderate negative correlation between CDAI score with SIBDQ-9 score (Pearson's r: -0.768) and with EQ-5D index (r: -0.644).

CONCLUSION

HRQoL improved after intestinal resection in CD, irrespective of the postoperative therapy used (ADA or AZA). Outcomes in HRQoL were associated with prevention of endoscopic recurrence, since improvements in HRQoL were only significant in patients with endoscopic remission at 1 year.

Adalimumab vs Azathioprine in the Prevention of Postoperative Crohn's Disease Recurrence. A GETECCU Randomised Trial

BACKGROUND AND AIMS

Postoperative recurrence of Crohn's disease [POR-CD] is almost certain if no prophylaxis is administered. Evidence for optimal treatment is lacking. Our aim was to compare the efficacy of adalimumab [ADA] and azathioprine [AZA] in this setting.

METHODS

We performed a phase 3, 52-week, multicentre, randomised, superiority study [APPRECIA], in which patients with ileocolonic resection were randomised either to ADA 160-80-40 mg subcutaneously [SC] or AZA 2.5 mg/kg/day, both associated with metronidazole. The primary endpoint was endoscopic recurrence at 1 year [Rutgeerts i2b, i3, i4], as evaluated by a blinded central reader.

RESULTS

We recruited 91 patients [median age 35.0 years, disease duration 6.0 years, 23.8% smokers, 7.1% previous resections]. The study drugs were administered to 84 patients. Treatment was discontinued owing to adverse events in 11 patients [13.1%]. Discontinuation was significantly less frequent in the ADA [4.4%] than in the AZA group [23.2%] (dif.: 18.6% [95% CI 4.1-33.2], p = 0.011). According to the intention-to-treat analysis, therapy failed in 23/39 patients in the AZA group [59%] and 19/45 patients in the ADA group [42.2%] [p = 0.12]. In the per-protocol analysis [61 patients with centrally evaluable images], recurrence was recorded in 8/24 [33.3%] patients in the AZA and 11/37 [29.7%] in the ADA group [p = 0.76]. No statistically significant differences between the groups were found for recurrence in magnetic resonance images, biological markers of activity, surgical procedures, or hospital admissions.

CONCLUSIONS

ADA has not demonstrated a better efficacy than AZA [both associated with metronidazole] for prophylaxis of POR-CD in an unselected population, although tolerance to ADA is significantly better. ClinicalTrials.gov NCT01564823.

Incidence, clinical outcomes, and therapeutic approaches of capsule endoscopy-related adverse events in a large study population

INTRODUCTION

Capsule endoscopy (CE) has become a first-line tool for small bowel (SB) examination. However, adverse events (AEs), such as CE retention or aspiration, may occur. The aims of this study were to evaluate incidence, clinical outcomes and therapeutic approaches of CE-related AEs in the largest series published to date.

METHODS

Data from 5428 procedures performed at 12 institutions between August 2001 and January 2012 were retrospectively analyzed. Baseline patient characteristics; procedure; type, localization and symptoms before/after AEs; previous patency tests performed; therapeutic management and patient's outcome were recorded.

RESULTS

The overall incidence of CE-related AEs was 1.9%: 2.0% for SB, 0.9% for esophageal and 0.5% for colon CE. The incidence of capsule retention was significantly higher than capsule aspiration (1.87% vs. 0.003%; p < 0.05), in patients suffering from inflammatory bowel disease (IBD) than in obscure GI bleeding (OGIB) (3.3% vs. 1.5%; p < 0.05) and in patients with the combination of nausea/vomiting, abdominal pain and distension. The SB was the most frequent localization of retention (88.2%). The use of patency tests -except for Patency© capsule- before CE was not a good predictor for AEs. Most of the patients with AEs developed no or mild symptoms (97%) and were managed by non-surgical methods (64.4%).

CONCLUSIONS

CE-related AEs are uncommon and difficult to predict by imagiological examinations. SB retention, that is usually asymptomatic, is the most frequent AE. In absence of symptoms, non-surgical management of CE-related AEs is recommended.

Abstract P1-14-12: Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P)

Pathological evaluation of response after NAC is a controversial issue. M&P has been for years the most widely employed score. Recently RCB index, a new system including axillary evaluation, seems to improve prognostic discrimination.

PURPOSE: The aim of this study was to validate the RCB index as a method to define prognosis in a reallife cohort of EBC patients treated with NAC and compare it to M&P system.

METHODS: We performed a retrospective analysis of our database. Patients with stage I-III considered candidate for NAC between January 2003 and August 2011 were included. RCB and M&P were calculated as previously published. Hormone receptor expression (RH), and Her2 were assessed following international guidelines. The Harell c-index and Roc curves were used to compare the prognostic value of RCB and M&P. Clinical, therapeutic and pathological data were obtained from medical records. A correlation with disease-free survival (DFS) and overall survival (OS) was done using the Kaplan-Meier method and Cox regression model.

RESULTS: 333 patients were included in this study. Distribution of breast cancer subtypes was: luminal 50.9%, Her2+ 31% and triple negative 18.1%. Mean tumour size was 42.3 mm. The majority of the patients had histhological grade II-III tumours (87.3%), with N stage 0-1 (97.3%). 87.4% received anthracycline and taxane-based NAC, associated to trastuzumab in her 2+ patients. Pathological complete response was 14% for the global population, being 30% for TN and 21.3% Her2+ subtypes. With a median follow-up of 56.3 months, DFS and OS at 5 years were as follows: RCB-0 93.6% and 97.9%, RCB-I 84.2% and 98.2%, RCB-II 79.1% and 89.5%, RCB-III 38.3% and 63.6%. Harell c-index value of RCB was statistically superior to M&P in both DFS (0.80 vs 0.68, p= 0.001) and OS (0.87 vs 0.69, p&lt;0.001 ). This superiority value of RCB was consistent among all breast cancer subtypes.

CONCLUSION: RCB index is as more accurated prognostic score to predict DFS and OS compared to M&P.

Citation Format: Pons V, BurguÉs O, PÉrez-Fidalgo JA, MartÍnez MT, Pinilla K, Bermejo B, Lluch A. Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-12.

Abstract P1-14-13: Residual proliferative cancer burden (RPCB) is superior to RCB index as prognostic tool in early breast cancer patients (EBC) treated with neoadjuvant chemotherapy (NAC)

BACKGROUND: Many different scales have been developed in order to assess response to NAC. Apart from Miller and Payne and RCB systems, recently the addiction of post-NAC pathological Ki 67 (yp Ki67) to RCB, called RPCB system, has been considered as a more accurate prognostic tool. The aim of this study is to assess the prognosis value of RPCB in a routine practice cohort and to compare it to RCB index and ypKi67.

METHODS: We performed a retrospective analysis of our database. Patients with stage I-III considered candidate for NAC from July 2008 and August 2011 were included. RPCB and RCB were calculated as previously published. Hormone receptor expression (HR), ypKi 67 and Her2 were assessed following international guidelines. The Harell c-index were used to compare the prognostic value of RPCB, RCB and ypKi 67. Clinical, therapeutic and pathological data were obtained from medical records. A correlation with disease-free survival (DFS) and overall survival (OS) was done using the Kaplan-Meier method and Cox regression model.

RESULTS: From our database including 333 EBC patients treated with NAC 184 had data to calculate RPCB, RCB and ypKi 67, of whom 51.6% were HR+Her2- tumours, 21.7% HR+Her2+, 8.2% HR- Her2+ and 18.5% triple negative. Mean tumour size was 37.5 mm (25-45). The majority of the patients had histhological grade II-III tumours (84.2%) and N stage 0-1 (96.7%). 67.4% of the patients received anthracycline and taxane-based NAC, associated to trastuzumab in Her2+ patients (26.1%). Pathological complete response by subtypes were 6.3%, 17.5%, 60% and 26.5%, respectively. With a median follow-up of 49.9 months, DFS and OS at 36 months were 85.2% and 95.1%. In the multivariate analysis all three systems were prognostic for DFS (RPCB p&lt;0.001; RCB p=0.001; ypKi 67 p= 0.002) and OS (RPCB p&lt;0.001; RCB p=0.011; ypKi 67 p= 0.037). Comparison of Harell c-index for DFS between RCPB and RCB showed a trend of RPCB towards a more accurate prognostic power (0.89 vs 0.81, p=0.061) that was significant when comparing RCPB vs ypKi67 and RPCB vs ypKi67 (0.89 vs 0.77, p=0.010). However no statistically differences were found in terms of OS (RPCB vs RCB 0.85 vs 0.82, p=0.357 and RPCB vs ypKi67 0.85 vs 0.72, p= 0.088).

CONCLUSION: RPCB, RCB and ypKi67 are prognostic for both DFS and OS in EBC patients treated with NAC. RPCB is a more accurate prognostic tool than ypKi67 and showed a trend towards superiority compared to RCB.

Citation Format: Pons V, Pérez-Fidalgo JA, Burgués O, Martín P, Cejalvo JM, Bermejo B, LLuch A. Residual proliferative cancer burden (RPCB) is superior to RCB index as prognostic tool in early breast cancer patients (EBC) treated with neoadjuvant chemotherapy (NAC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-13.

Capsule endoscopy capture rate: Has 4 frames-per-second any impact over 2 frames-per-second?

AIM: To compare the current capsule and a new prototype at 2 and 4 frames-per-second, respectively, in terms of clinical and therapeutic impact.

METHODS: One hundred patients with an indication for capsule endoscopy were included in the study. All procedures were performed with the new device (SB2₄). After an exhaustive evaluation of the SB2₄ videos, they were then converted to “SB2-like” videos for their evaluation. Findings, frames per finding, and clinical and therapeutic impact derived from video visualization were analyzed. Kappa index for interobserver agreement and χ² and Student’s t tests for qualitative/quantitative variables, respectively, were used. Values of P under 0.05 were considered statistically significant.

RESULTS: Eighty-nine out of 100 cases included in the study were ultimately included in the analysis. The SB2₄ videos detected the anatomical landmarks (Z-line and duodenal papilla) and lesions in more patients than the “SB2-like” videos. On the other hand, the SB2₄ videos detected more frames per landmark/lesion than the “SB2-like” videos. However, these differences were not statistically significant (P > 0.05). Both clinical and therapeutic impacts were similar between SB2₄ and “SB2-like” videos (K = 0.954). The time spent by readers was significantly higher for SB2₄ videos visualization (P < 0.05) than for “SB2-like” videos when all images captured by the capsule were considered. However, these differences become non-significant if we only take into account small bowel images (P > 0.05).

CONCLUSION: More frames-per-second detect more landmarks, lesions, and frames per landmark/lesion, but is time consuming and has a very low impact on clinical and therapeutic management.

P2-17-07: Construction of a Predictive Model of Probability of Ovarian Function Recovery in a Series of Premenopausal Breast Cancer Patients with Chemotherapy-Induced Amenorrhea Switched to an Aromatase Inhibitor (AI) after Adjuvant Tamoxifen

Introduction: AI therapy is not recommended in breast cancer patients with conserved ovarian function as AI decreases estrogenic feedback leading to an increased of FSH and LH. In patients older than 40 and with prolonged amenorrhea, switching to an AI after tamoxifen therapy is a controversial approach but with an adequate follow-up for early detection of potential menses renewal it might be feasible. Several factors have been identified in the literature as clinical defining variables of CIA while other factors have been associated with high probability of permanent CIA. Among clinical defining variables are time from last menses date (LMD) and low estradiol (E2) levels. Risk variables for permanent CIA are chemotherapy schedule administered and advanced age. We aimed to construct a predictive model to identify high risk of renewal of menses after switching to AI in premenopausal patients with CIA lasting at least 1 year.

Methods: Based on defining and prognostic variables of CIA, a predictive model of high probability of permanent amenorrhea was constructed by assigning a score as follows:

1) Time from LMD to switching date &gt;3 years: 1 point, &lt; 3 years: 0 points

2) E2 levels &lt;20 ng/ml: 1 point, &gt;20 ng/ml or unknown: 0 points

3) Age &gt; 45 years: 1 point, &lt; or = 45: 0 points

4) Chemotherapy regimen administered: dose dense or high doses: 2 points, conventional doses regimen with anthracycline and taxanes: 1 point, conventional doses only anthracycline-based or other: 0 points. Final score obtained from 0 to 5 points was classified in two groups: Low-probability of permanent amenorrhea: score 0–2, and high probability of permanent amenorrhea: score 3–5. To validate this probability model we retrospectively analysed data from a prospective maintained database of early breast cancer patients, clinically premenopausal at diagnosis that were treated in our institution from May 2004 to December 2009. All patients had histologically confirmation of hormone-sensitive breast carcinoma at stage I-III. Therapy included in all cases adjuvant or neoadjuvant chemotherapy and adjuvant tamoxifen and all patients referred a CIA lasting at least 1 year. Since 2006, in most patients E2 levels before switching were determined.

Results: Validation of probability model was performed in our series of 102 premenopausal patients of whom 9 recovered ovarian function (prevalence ratio: 0.088).

P3-14-05: Evaluation of Residual Cancer Burden Index (RCBI) as a Predictor of Disease Free Survival in a Non-Selected Cohort of Breast Cancer Patients Treated in the Neoadjuvant Setting

INTRODUCTION: Pathologic complete response (pCR) is associated with long-term survival and is considered as the primary endpoint in neoadjuvant trials. Definition of pCR includes patients without residual disease of the breast, however the presence of nodal metastasis, minimal residual cellularity and residual in situ carcinoma were not consistently defined as pCR. These observations, lead Symmans et al to construct a new prognostic index, the RCBI, in which these important issues were incorporated. RCBI is classified into 4 different response subgroups, from RCB-0 or pCR to RCB-III or absence of response. The aim of our study was to assess the prognostic value for recurrence free survival of the RCBI in a cohort of unselected breast cancer patients treated in our institution.

PATIENTS AND METHODS: We performed a retrospective evaluation of samples of breast cancer patients treated with neoadjuvant treatment. RCBI was assessed by two highly trained pathologists. Patients included had a histological diagnosis of breast carcinoma before neoadjuvant treatment and were considered candidate for neoadjuvant therapy. Clinical variables including date and type of recurrence were obtained from clinical records. Prognostic accuracy of RCBI index was evaluated by comparison of the Kaplan-Meier survival curves of the 4 different groups of response by RCBI. Differences were assessed with log-rank.

RESULTS: Samples from 70 patients treated in the neoadjuvant setting from January 2003 to December 2006 were included in the analysis. Median age was 54.6 years (range 31–80), histhologic subtype was ductal carcinoma (87.1%), lobular carcinoma (8.5%), and other (4.2%). In biopsy, rate of estrogen receptor positive was 72.7%, progesterone receptor positive 62.1%, and rate of HER2 overexpression was 26.2%. Neoadjuvant therapy administered was anthracycline+taxanes chemotherapy (CT )in both sequential or combination schedules in 71.4%, anthracycline-based CT in 15.7%, and other in 12.9%. Most patients received from 6–10 cycles of neoadjuvant CT. 3 patients treated with only 4 cycles received adjuvant complementary CT. All patients with hormone-sensible tumors received adjuvant endocrine therapy and 20 patients received adjuvant trastuzumab. Number of responses by RCB-group was 5 patients (7.1%) with RCB-0, 12 patients (17.1%) with RCB-I, 35 (50%) with RCB-II, and 18 (25.7%) with RCB-III. With a median follow-up of 41.2 months (range 12.7−120.9 months) 22 patients (31.4%) have relapsed. Ratio of events/patients in each RCB group was 0/5 in RCB-0, 2 /12 in RCB-I, 8/35 in RCB-II and 15/18 in RCB-III. Differences in recurrence-free survival in each group was statistically significant with p=0.0002.

CONCLUSIONS: Our results suggest that RCBI might be an appropriate prognostic tool to predict disease-free survival in a non-selected population of breast cancer patients. Further validation of our results with a bigger sample size is needed.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-14-05.

P5-11-06: Immunohistochemistry Discordance between Primary and Recurrent Tumors in Breat Cancer. Analysis of Potential Influence of Technique Bias by Comparing Test-Results under Two Different Conditions

Introduction: Discordance in expression of estrogen (ER) or progesterone receptors (PgR) and HER2 has been previously described in several studies, having this discordance an important impact on therapeutic approach or even in survival. However it is unclear whether discordance is a reflex of a clonal differentiation to a more aggressive biological tumour or the consequence of technical biases or inter-explorer variability. We aimed to assess the role of technique biases in observed discordance between primary tumour (PT) and recurrent tumour (RT) by analyzing discordance in two different situations: routine versus optimal conditions.

Patients and methods: We conducted a retrospective study in patients (pts) diagnosed with a recurrent breast cancer in the Hospital Clinico of Valencia between January 2000 and June 2010. All patients had a previous histological diagnose of the PT and all underwent a second histological study of the RT. Discordance was assessed in terms of hormone-sensibility (HS) (any ER or PgR +) vs hormone-resistance (HR) (ER-/PgR -) and triple negativity (TN) (ER-, PgR-, HER2−) vs non-TN (any positive). Routine conditions were referred to the immunohistochemistry (IHC) assessment of the normal practice on the base of which therapeutic decisions were made. Routine conditions were performed in the Pathology Department of our institution but PT and RT were usually evaluated at different timing and ocasionally by different pathologists. In order to assess potential laboratory biases we repeated IHC analysis under optimal conditions. For these optimal conditions analyses, paired samples from both PT and RT were reassessed at the same time and tests were performed in the same way. Final determination of the results was made by two highly trained pathologists and in case of disagreement in any determination, both explorers re-assessed the sample at the same time.

We evaluated discordance between PT and RT under both conditions, and the accuracy of determinations in PT or RT between both conditions.

Results: 128 paired samples (from 64 different pts) were analysed. Median age of the series was 48.5 years (range 27–83). Recurrences were loco-regional in 14 pts (21.9%) and distant in 50 pts (78.1%). RT tissue was obtained from skin and soft-tissues in 18 pts (28.1%), lung in 11 (17.2%), bone in 10 (15.6%), lymph nodes in 10 (15.6%), pleura/peritoneum in 9 (14.1%) and liver in 6 (9.4%). Discordant cases between PT an RT in terms of HS/HR were 30.4% in routine conditions and 9.8% in optimal conditions. In terms of TN/non-TN were 14.3% in routine vs 8.2% in optimal conditions. Accuracy in results HS/HR between routine and optimal conditions was 80.7% in PT and 76.0% in RT. In results of TN/non-TN accuracy between both conditions was 94.2% in PT and 87.2% in RT.

Conclusions: Results suggest that an important rate of discordance observed in routine conditions might be strongly influenced by technique biases. However, changes observed in optimal conditions with 9.8% discordance in HS/HR and 8.2% in TN/non-TN suggest that in a small proportion of tumours, observed discordance might be explained by biological mechanisms.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-11-06.

[Patient satisfaction in gastrointestinal endoscopy: results of a multicenter study]

BACKGROUND AND AIM

The aim of this study was to determine the main quality problems perceived by patients in gastrointestinal endoscopy through a satisfaction survey.

PATIENTS AND METHODS

A total of 321 patients from five gastrointestinal endoscopy units were included. Telephone interviews using a previously validated questionnaire on several aspects related to the procedure were carried out. Pareto analyses were performed to pinpoint the most common aspects among the vital few causes at each medical center. Based on the questionnaire, the satisfaction indicators were calculated for each center: the overall satisfaction score (the sum of the responses to the eight questions) and the rate of perceived problems (number of questions with a negative response divided by the number of questions asked).

RESULTS

The most frequent aspects among the vital few were waiting time for an appointment and discomfort during the examination, since both factors were included in the vital few in four of the five medical centers. Significant differences were found among centers in the overall satisfaction score (questionnaire score) (p < 0.001) and for the rate of perceived problems (p < 0.001).

CONCLUSION

According to the patients, the most problematic aspects were waiting time until the day of the appointment and discomfort during the examination. Perceived quality differed among the participating centers.

Variation among endoscopy units in the achievement of the standards of colonoscopic performance indicators

BACKGROUND/AIMS

To assess the achievement of quality standards of colonoscopy at six endoscopy units.

METHODOLOGY

Three indicators were used to assess the quality of 1056 colonoscopies performed at six hospitals: cecal intubation; adequate colon cleansing; and removal and recovery of all detected polyps. Analyses were performed on the total number of colonoscopies and on colonoscopies in which polyps were actually detected. The accomplishment of each indicator and a global compound index of all three indicators, named the Problem Rate, were analyzed. Results from each endoscopy unit were compared to previously established standards.

RESULTS

Adequate colon cleansing was the most frequent problem for quality in all centers; adequate colon preparation was 67% (range 50 to 84%). The cecum was reached in 84% of all colonoscopies (range 76 to 90%). 75% of all patients (range 28. 79%) had all polyps excised and recovered. All centers had rates below standard for one or several indicators (p<0.01, all cases). Two of the participant hospitals had an overall problem rate above the estimated standard (p<0.01).

CONCLUSIONS

There is a significant variation in the achievement of quality standards of colonoscopy between endoscopy units. Colon cleansing is the most frequent quality problem for colonoscopy.

Quantitative cholescintigraphy and bile abnormalities in patients with acalculous biliary pain

Acalculous biliary pain has been related to gallbladder dysfunction that produces a gallbladder emptying defect-a condition which favours the development of lithiasis. It is therefore probable that microlithiasis is present in patients with gallbladder dysfunction. The aims of this study were to measure gallbladder emptying and investigate bile abnormalities in patients with acalculous biliary pain. In 92 consecutive patients, gallbladder emptying was assessed by quantitative cholescintigraphy (abnormal ejection fraction < or =40%). In 64 patients, a microscopic study was performed on duodenal bile, defining abnormality as the presence of cholesterol crystals in any amount and/or calcium bilirubinate granules and/or microspheroliths at a rate of >10 per slide. The ejection fraction was abnormal in 45 patients (49%) (median 25.1%, range 6.8-39.3%) and normal in the remaining 47 cases (median 71.3%, range 41.0-96.1%). Bile was abnormal in 32 of 64 patients (50%), the most frequent finding being calcium bilirubinate granules. In the patients with bile abnormalities, abnormal ejection fraction was more frequent (20 of 32) and the median ejection fraction was lower (30.9%, range 12.0-94.1%) than in the patients with normal bile (16 of 32 with an abnormal ejection fraction; median ejection fraction 50.7%, range 6.8-96.1%). Abnormal bile was frequent (55.5%) in patients with reduced ejection fraction, but was not uncommon in patients with normal ejection fraction (33.3%). Fewer patients showed no alteration (25%). It is concluded that in most patients, acalculous biliary pain coexists with gallbladder dysfunction or abnormal bile, the combination of both alterations being common.

Quantitative cholescintigraphy: selection of random dose for CCK-33 and reproducibility of abnormal results

Dynamic cholescintigraphy (DCG) is a valid technique for evaluating gallbladder emptying. Cholecystokinin (CCK) as a slow infusion is recommended as a contraction stimulus. The normal ejection fraction (EF) has been shown to be reproducible, although the reproducibility of abnormal results has not been investigated. The aims of the present study were to standardize the CCK administration method (phase 1), obtain EF normality values (phase 2), and evaluate the reproducibility of abnormal results in patients with clinically suspected gallbladder dysfunction (phase 3).

METHODS

Phase 1 included 40 healthy volunteers divided into 4 groups (n = 10) and subjected to intravenous CCK infusion according to 4 different regimens (0.25, 0.30, 0.40, and 0.60 Ivy dog units [IDU]/kg). Phase 2 comprised 33 healthy volunteers for determining DCG normality values, and phase 3 evaluated the reproducibility of abnormal results in 44 patients having clinical manifestations compatible with gallbladder dysfunction and showing an abnormal EF in a previous study.

RESULTS

The most effective CCK infusion regimen was 0.40 IDU/kg (3.07 ng/kg) over 20 min, because it afforded the least variability and a high EF. When this regimen was applied to the healthy population, the EF was found to be 74.2% +/- 17.1% (mean +/- SD); the inferior normality limit was estimated to be 40%. Abnormal results were recorded in 77% (95% confidence interval, 62%-89%) of the patients. When the 2 DCG studies of phase 3 were compared, the EF correlation coefficient between them was 0.439 (P = 0.003).

CONCLUSION

Slow CCK infusion is the best regimen for stimulating gallbladder contraction; an EF of less than 40% is estimated to represent abnormality. The abnormal results for the EF in patients with clinically suspected gallbladder dysfunction proved to be reproducible.

[Dynamic ultrasonography in the diagnosis of gallbladder dysfunction: reliability of a simple method with easy clinical application]

AIMS

Although the results of dynamic ultrasonography (DUS) are similar to those of dynamic cholescintigraphy (DCS) in the study of gallbladder function, the methodology required for this technique is laborious and sometimes complex. The aim of this study was to investigate the reliability of a simple method of DUS to evaluate gallbladder function using DCS as a reference.

PATIENTS AND METHODS

Gallbladder function was studied using DUS and DCS in 80 consecutive patients with clinical findings compatible with gallbladder dysfunction. For DUS the ellipsoid method was used with measurement of three gallbladder diameters (transversal, longitudinal and anteroposterior) in basal conditions and after applying a cholecystokinetic stimulus (meal test); gallbladder emptying of less than 50% was considered abnormal. In DCS intravenous cholecystokinin (CCK) (0.40 IDU/kg in 20 minutes) was used as stimulus and an ejection fraction < or = 40% was considered abnormal.

RESULTS

In 15 patients (19%; 95% CI, 11-29%) abnormal gallbladder response was found using DUS. The ejection fraction in the entire group of patients studied was 48 26.2%. Ejection fraction was abnormal in 41 patients (51%; 95% IC, 40-63%) with a value of 25 8.5% and was normal in 39 patients (49%; 95% IC, 40-63%) with a value of 71.5 14.5%. The correlation coefficient between the values of gallbladder emptying calculated with DUS and the ejection fraction obtained with DCS was 0.199 (p = 0.079). When patients were divided according to gallbladder emptying measured by DUS and the ejection fraction obtained with DCS the concordance was very low (k = 0.065; EE = 0.085).

CONCLUSIONS

DUS performed using a simple technique lacks diagnostic value in gallbladder dysfunction when DCS is taken as a reference test

[Endoscopic treatment of pancreatitis and its complications]

OBJECTIVES

To study the long- and short-term safety and efficacy of endoscopic treatment of pancreatitis and its complications in our environment.

PATIENTS AND METHODS

We performed a retrospective analysis of 43 patients with chronic pancreatitis, acute pancreatitis complicated with pseudocyst, and pancreatic fistula diagnosed by endoscopic retrograde cholangiopancreatography who were suitable for endoscopic treatment.

RESULTS

Endoscopic treatment was attempted in 35 patients. The indication for treatment was pain in 17 patients (48.5%), jaundice in 7 (20%), pseudocyst in 10 (28.5%) and suspected external fistula in 1 (3%). The technique was successfully performed in 28 (80%). Of the patients with pain, pancreatic prosthesis was inserted in 13 and extracorporeal lithotripsy was applied in 6. Sixty-five percent of the patients improved. Of the 7 patients with jaundice, all had secondary stenosis of the biliary tract. Treatment was applied in 2, who showed partial improvement. Of the 15 patients with pseudocyst, endoscopic treatment was indicated in 10; the technique was successfully performed in 8 and complete resolution was achieved in 7 (87.5%). The patient with external fistula was treated with transpapillary prosthesis and complete resolution of disruption of Wirsung's duct was achieved. Overall improvement in successfully treated patients was: complete in 19 (68%), partial in 3 (18%), no improvement in 4 (14%) and 2 patients were lost to treatment. There were 4 short-term complications. There were 4 deaths and one was related to the technique.

CONCLUSIONS

Endoscopic treatment of chronic pain in chronic pancreatitis, pseudocysts and fistulas was effective in our environment with a low rate of complications.

[Endoscopic treatment combined with extracorporeal shock wave lithotripsy of difficult bile duct stones]

OBJECTIVES

The aim of this study was to determine the safety and effectiveness of extracorporeal shock wave lithotripsy (ESWL) in difficult bile duct stones resistant to endoscopic extraction.

PATIENTS AND METHOD

From January 1997 to February 2002, combined treatment with endoscopy and ESWL was used in 19 patients who had undergone unsuccessful endoscopic bile duct stone extraction after sphincterotomy. The procedure was carried out using analgesic and sedative drugs or deep sedation, prophylactic antibiotic therapy, and monitoring of vital signs. Bile duct stone localization was performed by contrast injection through nasobiliary drainage and fluoroscopy. After each ESWL session, lavage was performed through drainage and stone fragments were extracted endoscopically.

RESULTS

The 19 patients presented high surgical risk due to advanced aged and/or concomitant diseases. All presented jaundice and pain and nine (47.3%) presented associated cholangitis. Thirty ESWL sessions were performed (1.57 sessions per patient), with a mean of 2,120 shock waves per session. In 16 of the 19 patients (84.2%), combined treatment with ESWL and subsequent instrumental endoscopic extraction achieved complete clearance of the biliary tract. The treatment failed in 3 patients who were referred for surgical treatment. No early or late complications were observed, except in one patient who presented a self-limiting febrile syndrome.

CONCLUSIONS

Therapeutic endoscopy combined with ESWL is safe and effective in patients with difficult bile duct stones. It represents a therapeutic alternative in patients at high surgical risk.

Enterophilins, a new family of leucine zipper proteins bearing a b30.2 domain and associated with enterocyte differentiation

Enterocyte terminal differentiation occurs at the crypt-villus junction through the transcriptional activation of cell-specific genes, many of which code for proteins of the brush border membrane such as intestinal alkaline phosphatase, sucrase-isomaltase, or the microvillar structural protein villin. Several studies have shown that this sharp increase in specific mRNA levels is intimately associated with arrest of cell proliferation. We isolated several clones from a guinea pig intestine cDNA library. They encode new proteins characterized by an original structure associating a carboxyl-terminal B30.2/RFP-like domain and a long leucine zipper at the amino terminus. The first member of this novel gene family codes for a 65-kDa protein termed enterophilin-1, which is specifically expressed in enterocytes before their final differentiation. Enterophilin-1 is the most abundant in the small intestine but is still present in significant amounts in colonic enterocytes. In Caco-2 cells, a similar 65-kDa protein was recognized by a specific anti-enterophilin-1 antibody, and its expression was positively correlated with cell differentiation status. In addition, transfection of HT-29 cells with enterophilin-1 full-length cDNA slightly inhibited cell growth and promoted an increase in alkaline phosphatase activity. Taken together, these data identify enterophilins as a new family of proteins associated with enterocyte differentiation.

[Chondrosarcoma of the infratemporal fossa with intracranial extension. Case report and review of the literature]

Chondrosarcomas are rarely observed in the infratemporal fossa. We report a rare case with temporal extension into the middle cerebral fossa without meningoencephalic invasion. Surgical excision was followed by radiotherapy. The patient died 7 years later from another cause free of tumoral recurrence. We discuss the current understanding of cephalic chondrosarcomas involving the infratemporal fossa.

[Treatment with omeprazole, clarithromycin and amoxicillin over 6 days in patients with Helicobacter pylori-infected duodenal ulcer]

OBJECTIVE

To investigate the eradication rate of Helicobacter pylori with omeprazole, amoxicillin and clarithromycin during 6 days in patients with duodenal ulcer. To compare the reliability of the analysis of the eradication with urea-13C breath test performed one month and 3 months after therapy. To evaluate the one-year reinfection rate.

PATIENTS AND METHODS

Prospective study including 99 patients with duodenal ulcer (65 with acute disease and 34 in maintenance treatment) infected by Helicobacter pylori (urease rapid test and urea-13C breath test positive). Patients were treated with omeprazole 20 mg, clarithromycin 500 mg and amoxicillin 1 g, b.i.d., during 6 days. The infection status was investigated 1 and 3 months after treatment by urea-13C breath test. The one-year reinfection rate was investigated using the same test.

RESULTS

Per protocol eradication rates were 76% (95%-CI: 66-84) one month and 73% (95%-CI: 63-81) 3 months after treatment. In the intention to treat analysis, eradication rates were 74% (95%-CI: 64-82) and 70% (95%-CI: 60-79), respectively. Side effects were mild and uncommon. The rate of false negative urea-13C breath test results one month after therapy with respect to 3 months was 4.2% (95%-CI: 0.8-11.7). One-year reinfection rate determined in 56 patient was absent.

CONCLUSIONS

The eradication of Helicobacter pylori with triple therapy for 6 days in patients with duodenal ulcer is not satisfactory. To investigate Helicobacter pylori infection with urea-13C breath test one month after treatment overestimates the results of the eradication. One-year reinfection rate is clinically irrelevant.

Oropharyngeal candidiasis in patients with AIDS: randomized comparison of fluconazole versus nystatin oral suspensions

A total of 167 human immunodeficiency virus (HIV)-infected patients with oropharyngeal candidiasis were randomly assigned to receive 14 days of therapy with liquid suspension fluconazole (100 mg once daily) or liquid nystatin (500,000 U four times daily). At day 14, 87% of the fluconazole-treated patients were clinically cured, as opposed to 52% in the nystatin-treated group (P < .001). Fluconazole eradicated Candida organisms from the oral flora in 60%, vs. a 6% eradication rate with nystatin (P < .001). The fluconazole group had fewer relapses noted on day 28 (18%, vs. 44% in the nystatin group; P < .001). This relapse difference no longer existed by day 42. Fluconazole oral suspension as a systemic therapy was more effective than liquid nystatin as a topical therapy in the treatment of oral candidiasis in HIV-infected patients and provided a longer disease-free interval before relapse.

[Focal nodular hyperplasia of the liver: benign lesion with often surgical treatment. Magnetic resonance and laparoscopic findings]

The diagnosis of benign hepatic tumor lesions is every day more frequent. Three cases of focal nodular hyperplasia (FNH) accidently detected during the performance of echography and/or CAT for other reasons are presented. The difficulty or diagnostic doubts which the different imaging techniques may present before these findings, together with the relatively young age of these patients may lead to the adoption of a surgical attitude in lesions of a clearly benign character. The role of magnetic resonance (MR) as a non invasive diagnostic technique in this type of disease is of note.

Endoscopic sclerotherapy versus oesophageal transection in the prevention of variceal rebleeding

OBJECTIVE

To compare sclerotherapy with oesophageal transection in the prevention of rebleeding in patients with oesophageal varices.

DESIGN

A prospective trial.

PATIENTS

Forty-one patients with cirrhosis and variceal bleeding.

METHODS

After recovering from an acute episode of oesophageal variceal bleeding patients were randomized into two groups. One patient was excluded. Twenty-two patients were treated with sclerotherapy (group 1) and 18 underwent an oesophageal transection (group 2), with a shorter elapsed time from randomization to treatment in group 1. Both groups were similar with regard to clinical and biochemical features and variceal size. Failure, defined in group 1 as rebleeding or incomplete eradication after four sclerotherapy sessions, occurred in five (22.7%) patients; in group 2, rebleeding occurred in two (11.1%) patients (no statistically significant difference).

CONCLUSION

Although the survival rate was similar in both groups, sclerotherapy is preferable to oesophageal transection because it requires a shorter duration of hospitalization and has fewer complications.

Therapy for oropharyngeal candidiasis in HIV-infected patients: a randomized, prospective multicenter study of oral fluconazole versus clotrimazole troches. The Multicenter Study Group

A total of 334 HIV-infected patients with oral candidiasis were randomly assigned to receive 14 days of treatment with either 100 mg of oral fluconazole once daily or 10 mg clotrimazole five times daily. Both treatments were clinically effective: 98% of evaluable fluconazole-treated patients and 94% of evaluable clotrimazole-treated patients were cured or showed improvement (p = NS). Fluconazole was more effective than clotrimazole in eradicating Candida from the oral flora by the end of therapy (65% versus 48%) (p = 0.005). In addition, patients in the fluconazole-treated group were more likely to remain asymptomatic through the second week of follow-up (82.3% versus 50.0%) (p < 0.001). This difference was no longer evident by the post-therapy visit during week 4. Seven patients treated with clotrimazole and two patients treated with fluconazole discontinued therapy because of side effects. Two patients in the fluconazole group were withdrawn from therapy because of elevated serum glutamic-oxaloacetic transaminase levels, one considered possibly related to drug therapy. Fluconazole was as effective as clotrimazole in the treatment of oral candidiasis and temporarily provided a more prolonged disease-free state. Future studies are needed to define the optimal regimen for both the treatment and prevention of recurrent oral candidiasis in HIV-infected patients, addressing special attention to the issue of compliance, cost, and emergence of resistance.

A comparative study of blood lactate analytic methods

Three different blood lactate analytic methods were tested for precision, accuracy, linearity, and intermethod comparison: a photoenzymatic assay (PHE), and three electroenzymatic (EE) semiautomatic assays (EE1, EE2, EE3). Reference standards and duplicate capillary blood samples from the earlobe were used. Precision and accuracy of the three techniques, when measuring L-lactate standards, were good in the whole range of measurement (mean variation coefficient, VC = 1.78-3.38%; mean difference = 1.81-3.38%). Correlation between the three methods was high (r = 0.913-0.946), but all three electroenzymatic techniques systematically measured lower values as compared to the PHE tests. The differences ranged from 0.1-1.2 (5 mmol.l-1 PHE level), to 3.4-5.7 (20 mmol.l-1 PHE level). These differences were drastically reduced when a hemolyser and a glycolytic inhibitor were added to the sample prior to the assay. The measurements obtained in capillary blood by the three techniques are not equivalent. The differences are partially attributed to the fact that the PHE technique measures total blood lactate, while the EE methods only measure plasmatic-extraerythrocytic lactate. Some regression equations are presented that may be used to convert values measured by the PHE technique, to EE values and vice versa.

Differentiation of aseptic and bacterial meningitis in postoperative neurosurgical patients

The differentiation of bacterial from aseptic meningitis in postoperative neurosurgical patients has traditionally been based on the clinical setting, a recent history of steroid administration, and cerebrospinal fluid (CSF) studies, including the total and differential leukocyte counts, Gram stain, glucose, and total protein. Recent reports questioning both the validity of a relative CSF lymphocytosis in excluding bacterial meningitis and the usefulness of standard CSF testing prompted the authors to reevaluate these standard criteria. The type of operation, the presence of a foreign body, use of steroids, postoperative day on which symptoms developed, altered mental status, neck stiffness, headache, and nausea were not helpful in the differential diagnosis. High fever, new neurological deficits, an active CSF leak, and elevated leukocyte counts in the CSF and peripheral blood favored a bacterial etiology. The CSF glucose level and the differential leukocyte count were less helpful. No criterion or combination of criteria was sensitive and specific enough to reliably differentiate aseptic from bacterial meningitis in the majority of patients. The possibility of improving diagnostic accuracy with newer tests, such as CSF lactate, ferritin, total amino acids, C-reactive protein, and amyloid-A, should be assessed.

Non-O:1 Vibrio cholerae bacteremia: case report and review

A case of non-O:1 Vibrio cholerae bacteremia and prostatic abscess in a patient with idiopathic aplastic anemia was studied, and the data were compared with those from 23 previously reported cases of non-O:1 V. cholerae bacteremia. The case-fatality rate for the 13 cases for which the outcome is known is 61.5%. The majority of known cases have occurred in immunocompromised patients, particularly those with hematologic malignancy or cirrhosis. Host susceptibility is potentially important in this condition. Bacterial products such as a cholera-like toxin and El Tor hemolysin also may play a role in the disease process. The incidence of enteritis due to non-O:1 V. cholerae is unclear because of the methods used for routine stool culture; however, the small number of reported isolates from blood is likely to reflect the infrequency of bacteremia, since Vibrio species are readily identifiable on sheep blood agar. While non-O:1 V. cholerae is sensitive to most antibiotics in vitro, no data are available on antibiotic efficacy.

The localization of 1,25-dihydroxycholecalciferol in bone cell nuclei of rachitic chicks

1. A simple technique has been developed to obtain subcellular fractions of chick bone. The method yielded 60-70% of total DNA in the nuclear debris fraction and 80-90% of total (14)C recovered in bone after a dose of radioactive vitamin D. 2. After a dose of [4-(14)C,1,2-(3)H(2)]cholecalciferol (0.5mug) was given to vitamin D-deficient chicks, the time-course of total (14)C radioactivity in the epiphysis, metaphysis and diaphysis of proximal tibiae was measured. The maximum concentrations were reached at 6h, corresponding to a similar peak of radioactivity in blood, decreasing until 24h and indicating the dependence on the circulating (14)C and on the blood supply of the three bone components. 3. The (14)C radioactivity of cholecalciferol and 25-hydroxycholecalciferol (expressed per mg of DNA) followed the pattern of incorporation of total (14)C radioactivity in all three bone components. The more polar metabolite fraction reached a peak of radioactivity at 6-9h and maintained its concentration over the 24h period studied in all anatomical bone components. 4. After a dose of [4-(14)C,1-(3)H]cholecalciferol (0.5mug) was given to vitamin D-deficient chicks, the subcellular distribution was studied. At 24h after dosing, the nuclear fraction contained 27% and the supernatant fraction had 67% of total (14)C recovered in the bone filtrate. When the (14)C in the residual bone fragments was included, the nuclear fraction contained up to 35% of the total radioactivity in the bone. 5. The subcellular distribution pattern of individual vitamin D metabolites indicated that the purified nuclear fraction concentrated the polar metabolite, which lost (3)H at C-1, so that 77% of the radioactivity could be accounted for by 1,25-dihydroxycholecalciferol. The supernatant fraction contained smaller amounts of 1,25-dihydroxycholecalciferol (9%), with 66% of 25-hydroxycholecalciferol forming the major metabolite, corresponding to its concentration found in blood at 24h. 6. The preferential accumulation of 1,25-dihydroxycholecalciferol in the nuclear fraction and the overall pattern of other metabolites, found previously in intestinal tissue, suggests a similar mechanism of action in bone to that postulated for the intestinal cell in calcium translocation.