Centralization of Pancreaticoduodenectomy: A Systematic Review and Spline Regression Analysis to Recommend Minimum Volume for a Specialist Pancreas Service

OBJECTIVE

Through a systematic review and spline curve analysis, to better define the minimum volume threshold for hospitals to perform (pancreaticoduodenectomy) and the high-volume center.

BACKGROUND

The pancreaticoduodenectomy (PD) is a resource-intensive procedure, with high morbidity and long hospital stays resulting in centralization towards high-volume hospitals; the published definition of high volume remains variable.

MATERIALS AND METHODS

Following a systematic review of studies comparing PD outcomes across volume groups, semiparametric regression modeling of morbidity (%), mortality (%), length of stay (days), lymph node harvest (number of nodes), and cost ($USD) as continuous variables were performed and fitted as a smoothed function of splines. If this showed a nonlinear association, then a "zero-crossing" technique was used, which produced "first and second derivatives" to identify volume thresholds.

RESULTS

Our analysis of 33 cohort studies (198,377 patients) showed 55 PDs/year and 43 PDs/year were the threshold value required to achieve the lowest morbidity and highest lymph node harvest, with model estimated df 5.154 ( P <0.001) and 8.254 ( P <0.001), respectively. The threshold value for mortality was ~45 PDs/year (model 9.219 ( P <0.001)), with the lowest mortality value (the optimum value) at ~70 PDs/year (ie, a high-volume center). No significant association was observed for cost ( edf =2, P =0.989) and length of stay ( edf =2.04, P =0.099).

CONCLUSIONS

There is a significant benefit from the centralization of PD, with 55 PDs/year and 43 PDs/year as the threshold value required to achieve the lowest morbidity and highest lymph node harvest, respectively. To achieve mortality benefit, the minimum procedure threshold is 45 PDs/year, with the lowest and optimum mortality value (ie, a high-volume center) at approximately 70 PDs/year.

Procedure-specific outcomes following gastrectomy for cancer compared by hospital volume and service capability

BACKGROUND

International literature recommends centralising gastric cancer surgery, however, with volumes that define 'high-volume resection' being higher than those in most major centres in Australia and New Zealand. These reports rarely focus on the difference between total (TG) and partial gastrectomy (PG). We assessed the impact of resection volume and service capability on operative mortality, morbidity and surgical quality in patients who had a PG and TG.

METHODS

Patients who had gastrectomy for adenocarcinoma, between 2001 and 2015, were collected from the Queensland Oncology Repository. Hospitals were characterised by cases-per-annum (high-volume [HV] ≥ 5 and low-volume [LV] < 5) and hospital service capability as (high-service [HS] and low-service [LS]), giving three hospital groups: HVHS, LVHS and LVLS. Chi-squared tests were used to compare post-operative mortality, morbidity, failure to rescue (FTR) from complications and surgical quality between these three groups.

RESULTS

There were 426 patients who had a TG and 827 having PG. HVHS centres performed 59% of PG with high surgical quality rates of: HVHS = 53%, LVHS = 34% and LVLS = 46% (p < 0.01). Surgical complications were highest in LVLS (LVLS = 19%, LVHS = 11%, HVHS = 11%; p = 0.02). There was no difference in 30-day mortality nor in FTR. For TG, HVHS performed 67% of these procedures, with lower 30-day mortality (2%) and FTR rates (5%) compared with LVHS (7%, 22%) and LVLS (12%, 28%; p < 0.01). There was no difference in operative morbidity and surgical quality between hospital groups.

CONCLUSION

Despite the 'high-volume' threshold for gastrectomy being the lowest described in the literature, we have shown that centralisation to HVHS centres was associated with lower operative mortality for TG and improved quality of surgery for PG.

Hospital characteristics associated with better 'quality of surgery' and survival following oesophagogastric cancer surgery in Queensland: a population-level study

BACKGROUND

The impact of hospital characteristics on the quality of surgery and survival following oesophagogastric cancer surgery has not been well established in Australia. We assessed the interaction between hospital volume, service capability and surgical outcomes, with the hypothesis that both the quality of surgery and survival are better following treatment in high-volume, high service capability hospitals.

METHODS

All patients undergoing oesophagectomy and gastrectomy for cancer in Queensland, between 2001 and 2015, were included. Demographic, pathology and outcome data were collected. Hospitals were categorized into high (HV) (≥5 gastrectomies; ≥6 oesophagectomies) and low volume (LV). Hospital service capability was defined as high (HS) and low (LS), and then linked to hospital volume: HVHS, LVHS and LVLS. Higher quality surgery was defined using six perioperative parameters. Univariable comparisons of quality of surgery between hospital groups used chi-squared tests. The 5-year overall survival was compared using log-rank tests and Cox proportional hazard models.

RESULTS

For both gastrectomy and oesophagectomy, higher quality surgery occurred more frequently in HVHS hospitals (gastrectomy: HVHS = 44.2%, LVHS = 23.1%, LVLS = 29.1% (P < 0.01); oesophagectomy: HVHS = 34.5%, LVHS = 24.4%, LVLS = 21.7% (P = 0.01)). Following oesophagectomy, the 3- and 5-year overall survival was better following treatment in HVHS (P < 0.01). There was no difference between the groups following gastrectomy.

CONCLUSION

In Queensland, the quality of surgery was higher in HVHS hospitals performing gastrectomy and oesophagectomy; however, the impact on cancer survival was only seen following oesophagectomy.

Essential Updates 2018/2019: Essential Updates for esophageal cancer surgery

Key papers to treatment of esophageal cancer surgery and reduction of postoperative complications after esophagectomy published between 2018 and 2019 were reviewed. Within this review there was a focus on minimally invasive esophagectomy (MIE), robot-assisted MIE (RAMIE), and centralization to high-volume center. Advantages of MIE, irrespectively of hybrid or total MIE, to prevent postoperative complications, especially pneumonia, were shown in comparison to open procedure. However, whether total MIE has evident effects or not, as compared to hybrid MIEs, still remains unclear. Differences between RAMIE and MIE were reported to be marginal, though the advantage of lymphadenectomy, especially along recurrent laryngeal nerve, has been suggested. Centralization to high-volume center evidently benefits esophageal cancer patients by improving short-term outcomes. The definition of high-volume center has not been established yet, though institutional structure and quality are thought to be important. Transmediastinal esophagectomy, currently developed, has a potential to be one radical option of MIE for esophageal cancer.