Does the benefit of sentinel node frozen section vary between patients with invasive duct, invasive lobular, and favorable histologic subtypes of breast cancer?

BACKGROUND: Although many questions regarding sentinel lymph node (SLN) biopsy in breast cancer have been answered by observational studies and, increasingly, by prospective trials, the role of intraoperative SLN assessment remains a matter of debate. Here we report in detail the results of intraoperative SLN assessment by frozen section (FS), with particular attention to variations in sensitivity and yield by histologic subtype, by tumor size, and by other clinicopathologic parameters. METHODS: Five thousand two hundred ninety-eight consecutive patients with clinical stage T1-3N0 invasive breast carcinoma had SLN biopsy with intraoperative FS at Memorial Sloan Kettering Cancer Center between 1996 and 2004. We report the results of FS by sensitivity (the proportion of all positive SLN detected by FS) and by yield (the proportion of all FS procedures in which the FS was positive). RESULTS: The sensitivity of FS was 61% overall, was higher for invasive duct (ID) than for invasive lobular (IL) cancers (62% vs. 52%; P = 0.006), and was marginally lower for favorable subtypes (46%; P = 0.26). The yield of FS was 21% overall, with no difference between ID and IL cancers (22% vs. 21%; P = 0.49), and with a substantially lower yield for favorable subtypes (3%; P < 0.001). The yield of FS increased with tumor size for ID and IL cancers (P < 0.001), but not for favorable subtypes. For both ID and IL cancers, the sensitivity and yield of FS were significantly higher with younger patient age, increasing tumor size, and lymphovascular invasion. The yield of FS was <10% for all patients with ID or IL tumors < or =1 cm in size who were older than 60 years of age. Among all FS-positive patients, only 45% were identified by the first FS, whereas 91% were cumulatively identified by the first, second, or third FS. CONCLUSIONS: For patients with ID and IL cancers, the overall sensitivity of FS is >50%, but the yield of FS is <10% for individuals > or =60 years of age with T1a/b tumors. Intraoperative FS may not be worthwhile for this low-yield subset, especially for patients with invasive breast cancer of favorable type.

Introduction of night shift call system for surgical trainees: a prospective self-controlled trial.

OBJECTIVE: The number of hours worked by specialty trainees has come under scrutiny recently. One approach aimed at decreasing the number of consecutive hours worked is the night shift call system (NSCS). This study aimed to determine the advantages and disadvantages of an NSCS compared with those of the conventional overnight call system (ONCS). SUBJECTS AND METHODS: Sixteen basic surgical trainees (BSTs) from our unit participated in this prospective, self-controlled trial. During April 2000, the conventional 1-in-4 ONCS with a post-call half-day off was instituted. From May to June 2000, each BST rotated to work 1 week of night duty (20.00-08.00) and 7 weeks of daytime duty. A battery of neuropsychological tests were administered to the group after call during the study period. RESULTS: On average the numbers of consecutive hours worked during the NSCS and ONCS periods were 12 and 28 hours, respectively. There was no difference in numbers of errors committed and no difference in discrepancy between diagnoses made on admission and discharge. Two of the simple neuropsychological tests (memory scanning and addition tests) showed a significant fall-off in performance during the ONCS period (P < 0.05). Most specialists preferred the ONCS, while the majority of the BSTs preferred the NSCS (P < 0.05). This was because without extra manpower, the overall workloads of senior staff were increased. CONCLUSIONS: The NSCS is 1 way of reducing work hours, and was associated with significantly less impaired cognition on the part of our BSTs. It is only feasible if extra relieving staff are available to cover daytime duties.