Robert E. Pennington

Dermal injection of radioactive colloid is superior to peritumoral injection for breast cancer sentinel lymph node biopsy: results of a multiinstitutional study.

ObjectiveTo determine the optimal radioactive colloid injection technique for sentinel lymph node (SLN) biopsy for breast cancer. Summary Background DataThe optimal radioactive colloid injection technique for breast cancer SLN biopsy has not yet been defined. Peritumoral injection of radioactive colloid has been used in most studies. Although dermal injection of radioactive colloid has been proposed, no published data exist to establish the false-negative rate associated with this technique. MethodsThe University of Louisville Breast Cancer Sentinel Lymph Node Study is a multiinstitutional study involving 229 surgeons. Patients with clinical stage T1–2, N0 breast cancer were eligible for the study. All patients underwent SLN biopsy, followed by level I/II axillary dissection. Peritumoral, subdermal, or dermal injection of radioactive colloid was performed at the discretion of the operating surgeon. Peritumoral injection of isosulfan blue dye was performed concomitantly in most patients. The SLN identification rates and false-negative rates were compared. The ratios of the transcutaneous and ex vivo radioactive SLN count to the final background count were calculated as a measure of the relative degree of radioactivity of the nodes. One-way analysis of variance and chi-square tests were used for statistical analysis. ResultsA total of 2,206 patients were enrolled. Peritumoral, subdermal, or dermal injection of radioactive colloid was performed in 1,074, 297, and 511 patients, respectively. Most of the patients (94%) who underwent radioactive colloid injection also received peritumoral blue dye injection. The SLN identification rate was improved by the use of dermal injection compared with subdermal or peritumoral injection of radioactive colloid. The false-negative rates were 9.5%, 7.8%, and 6.5% (not significant) for peritumoral, subdermal, and dermal injection techniques, respectively. The relative degree of radioactivity of the SLN was five- to sevenfold higher with the dermal injection technique compared with peritumoral injection. ConclusionsDermal injection of radioactive colloid significantly improves the SLN identification rate compared with peritumoral or subdermal injection. The false-negative rate is also minimized by the use of dermal injection. Dermal injection also is associated with SLNs that are five- to sevenfold more radioactive than with peritumoral injection, which simplifies SLN localization and may shorten the learning curve.

Defining the Optimal Surgeon Experience for Breast Cancer Sentinel Lymph Node Biopsy: A Model for Implementation of New Surgical Techniques

ObjectiveTo determine the optimal experience required to minimize the false-negative rate of sentinel lymph node (SLN) biopsy for breast cancer. Summary Background DataBefore abandoning routine axillary dissection in favor of SLN biopsy for breast cancer, each surgeon and institution must document acceptable SLN identification and false-negative rates. Although some studies have examined the impact of individual surgeon experience on the SLN identification rate, minimal data exist to determine the optimal experience required to minimize the more crucial false-negative rate. MethodsAnalysis was performed of a large prospective multiinstitutional study involving 226 surgeons. SLN biopsy was performed using blue dye, radioactive colloid, or both. SLN biopsy was performed with completion axillary LN dissection in all patients. The impact of surgeon experience on the SLN identification and false-negative rates was examined. Logistic regression analysis was performed to evaluate independent factors in addition to surgeon experience associated with these outcomes. ResultsA total of 2,148 patients were enrolled in the study. Improvement in the SLN identification and false-negative rates was found after 20 cases had been performed. Multivariate analysis revealed that patient age, nonpalpable tumors, and injection of blue dye alone for SLN biopsy were independently associated with decreased SLN identification rates, whereas upper outer quadrant tumor location was the only factor associated with an increased false-negative rate. ConclusionsSurgeons should perform at least 20 SLN cases with acceptable results before abandoning routine axillary dissection. This study provides a model for surgeon training and experience that may be applicable to the implementation of other new surgical technologies.

The effect of prior breast biopsy method and concurrent definitive breast procedure on success and accuracy of sentinel lymph node biopsy

BackgroundIt has been suggested that sentinel lymph node (SLN) biopsy for breast cancer may be less accurate after excisional biopsy of the primary tumor compared with core needle biopsy. Furthermore, some have suggested an improved ability to identify the SLN when total mastectomy is performed compared with lumpectomy. This analysis was performed to determine the impact of the type of breast biopsy (needle vs. excisional) or definitive surgical procedure (lumpectomy vs. mastectomy) on the accuracy of SLN biopsy.MethodsThe University of Louisville Breast Cancer Sentinel Lymph Node Study is a prospective multi-institutional study. Patients with clinical stage T1–2, N0 breast cancer were eligible. All patients underwent SLN biopsy and completion level I/II axillary dissection. Statistical comparison was performed by χ2 analysis.ResultsA total of 2206 patients were enrolled in the study. There were no statistically significant differences in SLN identification rate or false-negative rate between patients undergoing excisional versus needle biopsy. The SLN identification and false-negative rates also were not statistically different between patients who had total mastectomy compared with those who had a lumpectomy.ConclusionsExcisional biopsy does not significantly affect the accuracy of SLN biopsy, nor does the type of definitive surgical procedure.

Race and Ethnicity and Breast Cancer Outcomes in an Underinsured Population

BACKGROUND The disparity in breast cancer mortality between African American women and non-Hispanic white women has been the subject of increased scrutiny. Few studies have addressed these differences in the setting of equal access to health care. We compared the breast cancer outcomes of underinsured African American and non-Hispanic white patients who were treated at a single institution. METHODS We conducted a retrospective review of medical records for breast cancer patients who were treated at Wishard Memorial Hospital from January 1, 1997, to February 28, 2006. A total of 574 patients (259 non-Hispanic whites and 315 African Americans) were evaluated. A Cox proportional hazards regression analysis for competing risks was performed. All statistical tests were two-sided. RESULTS Sociodemographic characteristics were similar in the two groups, and both racial groups were equally unlikely to have undergone screening mammography during the 2 years before diagnosis. Most (84%) of the patients were underinsured. The median time from diagnosis to operation, receipt of adequate surgery, and use of all types of adjuvant therapy were similar in the two groups. Median follow-up was 80.3 months for non-Hispanic whites and 77.9 months for African Americans. After accounting for the effect of comorbidities, African American race was statistically significantly associated with breast cancer-specific mortality (African Americans vs non-Hispanic whites: 26.0% vs 17.5%, P = .028; hazard ratio [HR] of death = 1.64, 95% confidence interval [CI] = 1.06 to 2.55). Adjustment for age at diagnosis, clinical stage, and hormone receptor status attenuated the effect, and the effect of race on breast cancer-specific survival was no longer statistically significant (HR of death from breast cancer = 1.43, 95% CI = 0.89 to 2.30). After adjustment for sociodemographic factors, the hazard ratio for race was further attenuated (HR = 1.26; 95% CI = 0.79 to 2.00). CONCLUSIONS In this underinsured population, African American patients had poorer breast cancer-specific survival than non-Hispanic white patients. After adjustment for clinical and sociodemographic factors, the effect of race on survival was no longer statistically significant.

The effect of dedicated breast surgeons on the short-term outcomes in breast cancer.

Objective:The impact of breast surgeons on short-term outcomes in breast cancer care was compared at a single institution. Summary Background Data:Many studies have demonstrated a correlation between high procedural volume and lower mortality in technically challenging procedures. Breast cancer treatment has significant impact on patient behavior, psychology, and appearance. Therefore, evaluation of outcomes cannot be limited to only operative mortality and morbidity. We sought to determine the effect of dedicated breast cancer surgeons on short-term outcomes at a single institution. Methods:Wishard Memorial Hospital is the county hospital affiliated with the Indiana University School of Medicine. A retrospective review was performed of all patients from January 1, 1997, to February 28, 2006. On July 1, 2003, coverage for the Breast Clinic was changed from general surgeons (G) to breast surgeons (B). There were 596 patients included in the study period. Results:There were no significant differences in patient demographics or disease characteristics between the 2 time periods. For early stage (stage I and II) breast cancer, a higher percentage of patients underwent breast conservation in the breast surgeon period than in the general surgeon period (P = 0.04). Lumpectomy margins in breast conserving operations during the G period were more often positive (P = 0.025) or close (<1 mm) (P = 0.01). Similarly, the rates of re-excision lumpectomy were also significantly lower during the B period (21% vs. 39%, respectively, P = 0.01). Breast surgeons were more likely to perform the sentinel node procedure (P = 0.001). There were no differences in the use of adjuvant chemotherapy and radiation therapy. The use of hormonal manipulation, however, was significantly higher in the B group than in the G group (P < 0.0002). Conclusions:Surgeons specialized in diseases of the breast demonstrate significant improvement in short-term outcomes associated with breast cancer treatment at a single institution. The differences identified cannot be attributed to differences in institutional function, patient population, surgeon case volume, or on the influence of nonsurgeon physicians.

Compliance Differences Between Patients With Breast Cancer in University and County Hospitals

PURPOSE Compliance with recommended breast cancer treatments outside the context of a clinical trial differs from that in study populations. The purpose of this study was to examine differences in compliance of breast cancer treatments. PATIENTS AND METHODS We conducted a retrospective review of 529 patients treated at 2 teaching hospitals in the same city from 2003 to 2006. Compliance with adjuvant therapy recommendations and choice of breast-conserving operations were compared between a university hospital (UH) and a county hospital (CH). RESULTS The 2 populations demonstrated similar rates of breast conservation (72% vs. 69%). Although use of radiation therapy at the CH was acceptable (82%), patients at the UH were more likely to undergo radiation therapy (95%). The use of hormone therapy was similar at the UH and the CH (> 93%). Patients were more likely to follow physician recommendations for adjuvant chemotherapy at the UH (89%) compared with the CH (70%; P = .0005). Univariate analysis revealed that patient age, tumor size, stage, grade, and estrogen receptor status were all significant predictors of patient compliance with chemotherapy. Preoperative chemotherapy was a strong predictor of patient compliance with chemotherapy (P < .0001). In multivariate analysis, all of the factors predictive of patient compliance in univariate analysis remained significant except tumor grade. CONCLUSION Preoperative chemotherapy appeared to increase compliance compared with adjuvant chemotherapy in the CH population. Compared with national standards, breast-conserving operations and radiation therapy compliance can be accomplished in an acceptable percentage of underinsured patients.