In Selected Women with Breast Cancer and Positive Sentinel Lymph Node Metastases, Axillary Lymph Node Dissection May Not Be Needed
In a recent Weekly Update, the DynaMed Editors reported on a randomized trial with level 1 evidence showing that sentinel lymph node (SLN) resection alone is as effective as SLN resection plus axillary lymph node dissection (ALND) for women with node-negative invasive breast cancer. Another recent trial has compared SLN resection alone to SLN resection plus ALND in 856 women positive for SLN metastases. Women were randomized to have completion ALND or no ALND following a finding of metastatic disease in a SLN resection. Among the reasons for excluding patients from the trial were the presence of matted nodes, ≥ 3 SLNs with metastases, bilateral breast cancer, and gross extranodal disease at time of SLN resection. Comparing SLN resection alone vs. SLN resection plus ALND after median follow-up of 6.3 years, there were no significant differences in either local recurrence (1.8% vs. 3.6%) or regional recurrence (0.9% vs. 0.5%) (level 2 [mid-level] evidence). The trial was stopped early due to slow enrollment after enrolling only about half the calculated number of patients needed for 90% power (Ann Surg 2010 Sep;252(3):426).
For more information see the Breast cancer (female) topic in DynaMed.
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Preliminary Data Suggest that Low-Dose Computed Tomography (CT) Screening May Reduce Lung Cancer Mortality and All-Cause Mortality
Guidelines from USPSTF and Canadian Task Force for Preventive Health Care do not recommend lung cancer screening, even in persons who smoke. The National Lung Screening Trial (NLST) evaluated the efficacy of low-dose CT for lung cancer screening in 53,454 current and former smokers aged 55-74 years with a history of > 30 pack-years. Patients were randomized to low-dose CT vs. chest radiography offered at baseline and at 2 annual follow-up visits. Findings were announced in a preliminary, unpublished report from the trial's Data and Safety Monitoring Board. Initial screens were positive for abnormality in 27.3% vs. 9.2%. Lung cancers were detected in 649 patients by screening CT and in 279 patients by chest x-ray. Lung cancer mortality rates were 245.7 per 100,000 patient-years vs. 308.3 per 100,000 patient-years (p < 0.05). The DynaMed Editors estimate the overall lung cancer mortality at 1.345% vs. 1.697% (NNS 284, 95% CI 179-706). All-cause mortality rates were 1,117.2 per 100,000 patient-years with CT screening vs. 1,200 per 100,000 patient-years with radiography (p < 0.05), with estimated all-cause mortality 7.106% vs. 7.662% (NNS 178, 95% CI 100-926) (level 2 [mid-level] evidence). The trial was terminated early at an interim analysis in October 2010 due to a significant difference between groups that met a pre-specified stopping rule (NLST Data and Safety Monitoring Board statement 2010 Oct 28, National Cancer Institute Press Release 2010 Nov 4).
