Is cancer care best at high-volume providers?

Surgical specialization and training - its relation to clinical outcome for colorectal cancer surgery

RATIONALE, AIMS AND OBJECTIVES

Surgical sub-specialization has been considered to be a major factor in improving cancer surgery-related outcomes in terms of 5-year survival and disease-free intervals. In this article we have looked at the evidence supporting the improvement in colorectal cancer outcomes with 'colorectal specialists' performing colon and rectal surgery.

METHODS

A literature review was carried out using search engines such as Pubmed, Ovid and Cochrane Databases. Only studies looking at colorectal cancer outcome related to surgery were included in our review.

RESULTS

Specialist surgeons performing a high volume of colorectal cancer surgery demonstrated better 5-year survival rates in patients, with less local recurrence. This was most evident in surgery for rectal cancer, where an association with increased sphincter saving surgery was also seen. Total mesorectal excision is now the accepted treatment for rectal cancer and has markedly improved survival rates and decreased local recurrence.

CONCLUSION

The outcomes in colorectal surgery continue to steadily improve. The training of specialized colorectal surgeons is a major contributing factor towards this improvement.

Low-volume centre vs high-volume: the role of a quality assurance programme in colon cancer surgery

AIM

The study aimed to determine whether hospitals within a quality assurance programme have outcomes of colon cancer surgery related to volume.

METHOD

Data were used from an observational study to determine whether outcomes of colon cancer surgery are related to hospital volume. Hospitals were divided into three groups (low, medium and high) based on annual caseload. Cancer staging, resected lymph nodes, perioperative complications and follow up were monitored. Between 2000 and 2004, 345 hospitals entered 31,261 patients into the study: 202 hospitals (group I) were classified as low volume (<30 operations; 7760 patients; 24.8%), 111 (group II) as medium volume (30-60; 14,008 patients; 44.8%) and 32 (groups III) as high volume (>60; 9493 patients; 30.4%).

RESULTS

High-volume centres treated more patients in UICC stages 0, I and IV, whereas low-volume centres treated more in stages II and III (P<0.001). There was no significant difference for intra-operative complications and anastomotic leakage. The difference in 30-day mortality between the low and high-volume groups was 0.8% (P=0.023).Local recurrence at 5 years was highest in the medium group. Overall survival was highest in the high-volume group; however, the difference was only significant between the medium and high-volume groups. For the low and high-volume groups, there was no significant difference in the 5-year overall survival rates.

CONCLUSION

A definitive statement on outcome differences between low-volume and high-volume centres participating in a quality assurance programme cannot be made because of the heterogeneity of results and levels of significance. Studies on volume-outcome effects should be regarded critically.

A systematic review and critique of the literature relating hospital or surgeon volume to health outcomes for 3 urological cancer procedures

PURPOSE

We performed a systematic review and critique of the literature of the relationship between hospital or surgeon volume and health outcomes in patients undergoing radical surgery for cancer of the bladder, kidney or prostate.

MATERIALS AND METHODS

Four electronic databases were searched to identify studies that describe the relationship between hospital or surgeon volume and health outcomes.

RESULTS

All included studies were performed in North America. A total of 12 studies were found that related hospital volume to outcomes. For radical prostatectomy and cystectomy all 8 included studies showed improvement in at least 1 outcome measure with increasing volume and never deterioration. For nephrectomy the 4 included studies produced conflicting results. Four studies were found that related surgeon volume to outcomes. All radical prostatectomy and cystectomy studies showed that some outcomes were better with higher surgeon volume and never deterioration. We did not find any studies of the effect of surgeon volume on outcomes after nephrectomy. The 3 studies of the combined effect of hospital and surgeon volume on outcomes after radical prostatectomy or cystectomy suggest that high volume hospitals have better outcomes, in part because of the effect of surgeon volume and vice versa.

CONCLUSIONS

Outcomes after radical prostatectomy and cystectomy are on average likely to be better if these procedures are performed by and at high volume providers. For radical nephrectomy the evidence is unclear. The impact of volume based policies (increasing volume to improve outcomes) depends on the extent to which "practice makes perfect" explains the observed results. Further studies should explicitly address selective referral and confounding as alternative explanations. Longitudinal studies should be performed to evaluate the impact of volume based policies.

Threshold volumes for urological cancer surgery: a survey of UK urologists

OBJECTIVE

To determine minimum threshold levels of activity set by surgeons for urological cancer surgery, and to relate threshold levels to stated current procedural volume.

METHODS

In all, 307 consultant urological surgeons were sent a questionnaire asking them to state for four urological cancer operations of different complexity their current procedural volume; whether minimum volume thresholds per surgeon should be implemented; and if so, the level of such thresholds; 212 (69%) replied.

RESULTS

For all four procedures >/= 75% of surgeons advocated the setting of a minimum volume threshold. Overall, surgeons set the highest thresholds for radical prostatectomy and the lowest for radical cystectomy with continent diversion. There was no significant association between either the principle of supporting minimum volume thresholds or the level of such a threshold and the number of years worked as a consultant surgeon. The level of surgeon-derived minimum thresholds increased with increasing surgeon procedural volume.

CONCLUSION

Most surgeons supported the principle of setting minimum volume thresholds. These thresholds appear to be influenced by current procedural volume and by procedural complexity. By setting thresholds greater than their current volume, some surgeons implicitly indicate that their current volume is insufficient to maintain their surgical competency.

Influence of hospital procedure volume on ovarian cancer survival in Japan, a country with low incidence of ovarian cancer

The survival of ovarian cancer patients has been reported to be superior at hospitals with a high volume of operations. A population-based study was carried out to assess whether this is true in Japan, where the incidence rate is relatively low as compared with other developed countries. The Osaka Cancer Registry's data were used to investigate associations between hospital procedure volume and survival of ovarian cancer patients. Hospitals were ranked according to the number of operations for ovarian cancer performed per year (high/medium/low/very low). Survival analysis was restricted to the reported 2450 cases who lived in Osaka Prefecture (except for Osaka City) diagnosed in 1975-1995, or those who resided in Osaka City in 1993-1995, since active follow-up data on vital status 5 years after the diagnosis were available. The relative 5-year survival for all ovarian cancer cases was 38.8%, and the survival was higher with greater hospital volume (22.3% / 34.2% / 46.2% / 55.0%). After adjustment for age, histologic type and cancer stage by the Cox regression model, patients receiving care in very-low-volume hospitals were seen to have a 60% higher risk of death than patients receiving care in high-volume hospitals (P < 0.01). Although some limitations existed in this study, the results indicated that further centralization of operative treatment in high-volume hospitals might improve survival of ovarian cancer patients in Japan.

What Predicts Serious Complications in Colorectal Cancer Resection?

Virtually all volume-outcome studies use mortality as their outcome measure, yet most general surgical procedures have low in-patient death rates. We examined whether hospital surgical volume impacts other colorectal cancer resection outcomes and complications. Colorectal cancer (CRC) resections from 1996 to 2000 were identified using the California hospital discharge database. Comorbidity was graded using a modified Charlson index. Hospital CRC resection volume was calculated. Serious medical complications were defined as life-threatening cardiac or respiratory events, renal failure, or shock. Serious surgical complications were defined as vascular events, need for reoperation, or bleeding. Multivariate logistic regression analyses were performed to estimate the impact of predictors on complications. We identified 56,621 resections. Median age was 70 to 74 years. Eighty-one per cent of patients were white. Most had localized (57%) versus distant (22%) disease. Serious medical (17.5%) and surgical (9.8%) complications were not infrequent. In multivariate analyses, greater annual CRC surgical volume predicted lower odds of serious complication, but patient characteristics (age, comorbidity, and acuity of surgery) were more important. Although patients receiving CRC resection at lower-volume hospitals have greater odds of complication than patients treated at higher-volume institutions, patient factors remain the most important determinants of complication.

Breast cancer: do specialists make a difference?

BACKGROUND

Many believe that breast cancer should be treated by specialists. We studied the effect of surgeon and hospital specialization on survival after breast cancer treatment in a large, well-defined patient population.

METHODS

The Cancer Surveillance Program database for Los Angeles County was reviewed. Between 1990 and 1998, 43,411 cases of breast cancer were diagnosed, of which 29,666 had complete data on surgeon, hospital, and staging information. Patients were stratified on the basis of surgeon and hospital specialization, as well as by age, race, stage, surgical procedure, and surgeon and hospital case volume. An analysis of survival and its dependence on these factors was performed.

RESULTS

Age, race, socioeconomic status, tumor size, nodal status, extent of disease, surgeon specialization, surgeon case volume, and hospital case volume were all associated with 5-year survival after diagnosis of breast cancer. Treatment at a specialty center did not affect survival. Multivariate analysis indicated that type of surgeon was an independent predictor of survival (relative risk,.77), as were both hospital and surgeon case volume.

CONCLUSIONS

Treatment by a surgical oncologist resulted in a 33% reduction in the risk of death at 5 years. The effect of surgical specialization cannot be entirely attributed to volume effects.

The volume-outcome relationship: from Luft to Leapfrog

Numerous reports have documented a volume-outcome relationship for complex medical and surgical care, although many such studies are compromised by the use of discharge abstract data, inadequate risk adjustment, and problematic statistical methodology. Because of the volume-outcome association, and because valid outcome measurements are unavailable for many procedures, volume-based referral strategies have been advocated as an alternative approach to health-care quality improvement. This is most appropriate for procedures with the greatest outcome variability between low-volume and high-volume providers, such as esophagectomy and pancreatectomy, and for particularly high-risk subgroups of patients. Whenever possible, risk-adjusted outcome data should supplement or supplant volume standards, and continuous quality improvement programs should seek to emulate the processes of high-volume, high-quality providers. The Leapfrog Group has established a minimum volume requirement of 500 procedures for coronary artery bypass grafting. In view of the questionable basis for this recommendation, we suggest that it be reevaluated.

Is surgery getting safer? National trends in operative mortality

BACKGROUND

Although mortality rates for some cardiovascular procedures seem to have declined, it is unclear whether other high-risk procedures are becoming safer over time.

STUDY DESIGN

We examined national trends between 1994 and 1999 in operative mortality for 14 high-risk cardiovascular and cancer procedures in the national population of Medicare beneficiaries over age 65. Secular trends were examined using logistic regression adjusting for age, gender, race, socioeconomic status, admission acuity, comorbidities, and hospital volume.

RESULTS

Observed mortality rates varied widely across the 14 procedures, from 2% (carotid endarterectomy) to 16% (esophagectomy). Over the 6-year study period, average patient age increased for all procedures, and patients were more likely to undergo operation at high-volume hospitals for some procedures (pancreatic resection, esophagectomy, cystectomy, and pneumonectomy). After accounting for these changes, operative mortality declined significantly for three cardiovascular procedures, as evidenced by adjusted odds ratios (OR) for the 6-year effect on operative mortality (coronary artery bypass graft OR = 0.85, 95% confidence interval [CI] 0.81 to 0.88; carotid endarterectomy OR = 0.86,95% CI 0.80 to 0.93; mitral valve replacement OR = 0.89, 95% CI 0.81 to 0.97). In contrast, operative mortality did not decline for any of the cancer procedures. In fact, adjusted mortality increased for colectomy for colon cancer (OR= 1.13, 95% CI 1.07 to 1.19).

CONCLUSIONS

Although risks of some cardiovascular procedures are declining over time, there is no evidence that other types of high-risk surgery are becoming safer. These findings suggest the need for systematic efforts to monitor and improve surgical performance.