Australasian ACPGBI risk prediction model for 30-day mortality after colorectal cancer surgery

BACKGROUND

Postoperative mortality after colorectal cancer surgery varies across hospitals and countries. The aim of this study was to test the Association of Coloproctologists of Great Britain and Ireland (ACPGBI) models as predictors of 30-day mortality in an Australian cohort.

METHODS

Data from patients who underwent surgery in six hospitals between 1996 and 2015 (CRC data set) were reviewed to test ACPGBI models, and patients from 79 hospitals in the Bi-National Colorectal Cancer Audit between 2007 and 2016 (BCCA data set) were analysed to validate model performance. Recalibrated models based on ACPGBI risk models were developed, tested and validated on a data set of Australasian patients.

RESULTS

Of 18 752 patients observed during the study, 6727 (CRC data set) and 3814 (BCCA data set) were analysed. The 30-day mortality rate was 1·1 and 3·5 per cent in the CRC and BCCA data sets respectively. Both the original and revised ACPGBI models overestimated 30-day mortality for the CRC data set (observed to expected (O/E) ratio 0·17 and 0·21 respectively). Their ability to correctly predict mortality risk was poor (P < 0·001, Hosmer-Lemeshow test); however, the area under the curve for both models was 0·88 (95 per cent c.i. 0·85 to 0·92) showing good discriminatory power to classify 30-day mortality. The recalibrated original model performed well for calibration and discrimination, whereas the recalibrated revised model performed well for discrimination but not for calibration. Risk prediction was good for both recalibrated models. On external validation using the BCCA data set, the recalibrated models underestimated mortality risk (O/E ratio 3·06 and 2·98 respectively), whereas both original and revised ACPGBI models overestimated the risk (O/E ratio 0·48 and 0·69). All models showed similar good discrimination.

CONCLUSION

The original and revised ACPGBI models overpredicted risk of 30-day mortality. The new Australasian calibrated ACPGBI model needs to be tested further in clinical practice.

Surgical outcome after standard abdominoperineal resection: A 15-year cohort study from a single cancer centre

BACKGROUND

Abdominoperineal resection (APR) is associated with a poorer oncological outcome than anterior resection. This may be due to higher rates of intra-operative perforation and circumferential resection margin involvement. The aim of this study was to audit our short and long-term results of abdominoperineal resection performed using conventional techniques and to compare this with other published series.

MATERIALS AND METHODS

A retrospective review of all patients who had standard APR between January 2000 and December 2016 in a single institution, Cabrini Hospital, Melbourne, Australia. A total of 163 cases performed by nine different colorectal surgeons for primary rectal adenocarcinoma were identified, with their clinicopathological data analysed.

RESULTS

Using standard APR, only six patients (3.7%) were found to have a positive circumferential resection margin (CRM). There were two cases of intra-operative perforation (1.2%). Local recurrence rate was 5.6% of patients, with distant recurrence found in 24.9%. Disease-free survival at five years was 73.1%. Five-year overall survival was 66.7%, 67.9% of all deaths were cancer-related.

CONCLUSION

Short and long-term outcomes after standard APR in this study were comparable to previous published studies. The CRM rate of 3.7% compares favourably to published positive CRM rates for standard APR which ranged from 6 to 18%. Standard APR remains a viable technique for the treatment of rectal cancer. Patient selection and adequate training remain important factors.

Vitamin D metabolism and regulation in pediatric MSCs

Vitamin D is crucial for mineral homeostasis and contributes to bone metabolism by inducing osteoblast differentiation of marrow stromal cells (MSCs). We recently reported that MSCs from adults demonstrate 1α-hydroxylase activity in vitro and express vitamin D-related genes; this raises a possible autocrine/paracrine role for D activation in pre-osteoblasts. In this studies, we tested the hypotheses that pediatric MSCs have 1α-hydroxylase activity and express vitamin D-related genes. With IRB approval, we isolated MSCs from discarded excess iliac marrow graft from 6 male and 6 female subjects (age 8-12 years) undergoing alveolar cleft repair. 1α-hydroxylation of substrate 25(OH)D₃ was measured by ELISA for 1α,25(OH)₂D. RT-PCR was used for gene expression. Pediatric MSCs showed a range of 1α-hydroxylase activity in vitro. There was constitutive expression of vitamin D receptor (VDR), megalin, d-hydroxylases (CYP27B1, CYP27A1, CYP2R1, and CYP24A1), and estrogen receptor (ER). There was 2.6-fold greater expression of CYP27B1 and 3.5-fold greater expression of CYP24A1 in MSCs from boys compared with girls. There was 2.4-fold greater expression of ERα and 3.2-fold greater expression of megalin in MSCs from boys. In preliminary studies, treatment of female pediatric MSCs with 10nM 17β-estradiol resulted in upregulation of CYP27B1 and CYP24A1, as well as VDR, megalin, ERα, and ERβ. Treatment with 25(OH)D₃ upregulated CYP27B1, VDR, and ERα. Expression and regulation of vitamin D related genes in pediatric hMSCs reinforces an autocrine/paracrine role for vitamin D in hMSCs. Finding striking gender differences in MSCs from children was not seen with MSCs from adults and adds insight to the metabolic environment of bone and presents a research approach for investigating and optimizing pediatric bone health.

[Systemic effects of intravenous dipyridamole in patients of various age groups]

Aim of this study was to assess the role of age-related vascular response in the onset of i.v. dipyridamole effects. The results of 129 patients who underwent a dipyridamole infusion were reviewed. The patients were divided into three according to age: 47 patients of less than 50 years (group I), 54 patients aged between 50 and 60 years (group II) and 28 patients of more than 60 years (group III). For each group heart frequency (HF) and systolic blood pressure (SBP) were considered in basal conditions, at the end of infusion and at the minimum value of SBP (SBP min); moreover the time in reaching SBP min was considered (time to SBP min). At the end of the infusion no significant changes in SBP were observed in all groups while the SBP min value reached from group III were significantly lower than basal (142.6 +/- 20.4 mmHg, p less than 0.02). The HF, without significant differences among the three groups in basal conditions, increased significantly at the end of infusion only in group I and II, with a more significant increase in group I at the time of SBP min with respect to groups II and III. The group 3 showed moreover, a significant longer time to SBP min (286 +/- 208 sec) respect to the group I and II (145 +/- 130 and 160 +/- 177 sec respectively) (p less than 0.02). From these data it can resume that age could be a factor to determine hemodynamic response to intravenous dipyridamole.

[Relationship between arrhythmia profile, left ventricular function and sudden death in the post-infarct period of patients resuscitated from heart arrest]

In order to determine the relationship among ventricular arrhythmias, left ventricular dysfunction and sudden cardiac death (SCD), 75 consecutive patients with myocardial infarction, 38 of whom resuscitated from SCD, were studied retrospectively by 48 hour Holter electrocardiographic monitoring (ECGD), cardiac catheterization and radionuclide angiography (ACRD). The patients were divided in 3 groups, related to SCD occurrence and to the interval between acute myocardial infarction (AMI) and SCD: Group I (37 patients-control group) no cardiac arrest occurred; Group II (26 patients) resuscitated less than or equal to 48 hours after AMI; Group III (12 patients) resuscitated 6-12 weeks after AMI. ECGDs were recorded with an average of 2 (ECGD 1), 16 (ECGD 2) and 36 months (ECGD 3) after AMI. In ECGD 1, there were no differences in the frequency and complexity of ventricular arrhythmias among the 3 groups, whereas in ECGD 2 and 3 the incidence of complex ventricular arrhythmias was significantly higher in Group III than in the other 2 groups (p less than 0.05). In Group III, the complexity and frequency of ventricular arrhythmias increased both in ECGD 2 and 3 compared to ECGD 1 (p less than 0.05). Furthermore, between patients of Group II and III higher grade arrhythmias and more frequent ventricular premature beats (VPB) were noted in sudden death patients than in survivors. There was no statistical difference in mean cardiac index, left ventricular end-diastolic pressure and ejection fraction among the groups. In the ACRD 1 performed an average of 8 months after AMI, a slight decrease of ejection fraction in Group III compared to the other groups was noted (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)