Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy.

Importance: Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown. Objective: To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node. Design, Setting, and Participants: In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis. Exposure: Omission of ALND after SLNB or TAD. Main Outcomes and Measures: The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed. Results: A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55). Conclusions and Relevance: The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

Risk factors for emergency caesarean section in planned vaginal breech delivery.

PURPOSE: To identify risk factors for emergency caesarean section in women attempting a vaginal breech delivery at term. METHODS: Data from 1092 breech deliveries performed between 1998 and 2013 at a Swiss cantonal hospital were extracted from an electronic database. Of the 866 women with a singleton, full term pregnancy, 464 planned a vaginal breech delivery. Fifty-seven percent (265/464) were successful in delivering vaginally. Multivariate regression analyses of risk factors were performed, and neonatal and maternal complications were compared. RESULTS: Risk factors for failed vaginal delivery were peridural anaesthesia (OR 2.05; 95 % CI 1.09-3.84; p = 0.025), nulliparity (OR 2.82; 95 % CI 1.87-4.25; p < 0.001), high birth weight (OR 1.17; 95 % CI 1.04-1.30; p = 0.006) and induction of labour (OR 1.56; 95 % CI 1.003-2.44; p = 0.048). Maternal age, height and weight; gestational age; or newborn length and head circumference were not associated with an unplanned caesarean section. The rate of successful vaginal delivery in the low risk sub-group (multiparous women without induction of labour) was 58-83 %, depending on birth weight category. The likelihood of success for the high risk sub-group (nulliparous women with induction of labour) fell below a third at neonatal birth weights >3250 g. Complication rates were low in the cohort. CONCLUSIONS: Use of peridural anaesthesia, nulliparity, high birth weight and induction of labour were risk factors for unsuccessful vaginal breech delivery requiring an unplanned caesarean section. Awareness of these risk factors is useful when counselling women who are considering a vaginal breech delivery.