Abstract P2-12-03: Endofascial axillary lymphadenectomy – Towards a drainless protocol

Abstract Background: The pathogenesis of seroma formation following axillary dissection continues to be poorly understood, although it seems that the greater the surgical disruption of the axilla, the higher the incidence of seroma and lymphoedema. We have previously described the laminated, three-dimensional structure of the clavipectoral fascia (CPF) that is evident during axillary ultrasonography and dissection . We propose that reconstituting the CPF reduces dead space, partially restores pressure gradients and facilitates collateralization to improve lymphatic flow, thereby reducing the incidence of seromas. Herewith, is a description of our technique for reconstitution of the CPF and our experience thus far. Method: Technique: Following mastectomy or breast conservation surgery, the lateral border of pectoralis major is defined. Here, the medial, anterior laminae of the CPF are identified but not incised. Once the anterior extent of the CPF is displayed, a longitudinal incision is made through the midpoint of the CPF to access the axillary contents. If there is a substantial axillary tail, then the CPF is incised along the perimeter of the tail to include intra-mammary lymph nodes. A loose areolar tissue plane is encountered; the edges of the CPF are grasped and elevated and this areolar tissue plane developed by blunt and sharp dissection. Medially, this loose areolar tissue plane leads directly to a posterior gutter, and the long thoracic nerve on serratus anterior is identified and preserved. Superiorly, a deeper lamina of the CPF along the inferior border of the axillary vein has to be incised to find the thoracodorsal nerve. Identification of the intercostobrachial nerves is standard, as is the lateral dissection. Identification of the long thoracic nerve and thoracodorsal bundle results in definition of a vertical sheet, ‘the interneural tissue’. This can be grasped between the thumb and index finger and is excised en bloc. This tissue contains fat, lymph nodes and lymphatic vessels and is lined by thin fascial layers that we consider related to the CPF3. At this stage, the anterior laminae of the CPF and axilla are carefully palpated for any residual nodes. After haemostasis, the CPF is reconstituted with a running, absorbable ‘lymphostatic’ suture. No drain is placed in the axilla. Results: Between 2012 – 2015, 64 patients have undergone axillary dissection with reconstitution of the CPF in our unit.. The average age was 54 years (range 29-87 years). An average of 12 nodes were procured (range 2-26 nodes). Only 5 women (8%) required seroma aspiration. Conclusion: We have dispensed with axillary drains in those who have had reconstitution of the CPF and only a minority of our patients required axillary seroma aspiration. We believe this technique should be given consideration to decrease the use of drains following axillary dissection. Citation Format: Meredith IC, Popadich A, Mouat CH, Barrett K, King B. Endofascial axillary lymphadenectomy – Towards a drainless protocol. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-12-03.</jats:p

Incidence and Risk Factors for Occult Level 3 Lymph Node Metastases in Papillary Thyroid Cancer

Papillary thyroid cancer (PTC) frequently disseminates into cervical lymph nodes. Lateral node involvement is described in up to 50 % patients undergoing prophylactic lateral neck dissection. This study aimed to assess this finding and identify which factors predict for occult lateral node disease. Patients with fine needle aspiration-confirmed PTC (Bethesda V or VI), without evidence of cervical lymph node metastases, underwent a total thyroidectomy with prophylactic ipsilateral central and level 3 dissection. Level 3 nodes were removed by compartmental dissection or by sampling the sentinel nodes overlying the jugular vein, according to surgeon preference. Data were collected prospectively from January 2011 to August 2014. Statistical analysis was performed by SPSS software. A total of 137 patients underwent total thyroidectomy with prophylactic ipsilateral central and level 3 dissection for PTC. The incidence of occult level 3 disease was 30 % (41/137 patients). A total of 48 % of patients (66/137) harbored occult central neck disease. A total of 80.5 % of patients with pN1b disease had macrometastases (aeyen2 mm), and 15 % exhibited skip metastases with central compartment sparing. In patients with pN1b disease, a median of 6 level 3 nodes were retrieved, with an average involved nodal ratio of 0.29. Multivariate regression demonstrated risk factors for occult lateral neck metastasis include tumor size (odds ratio 1.1), upper pole tumors (odds ratio 6.6), and vascular invasion (odds ratio 3.2) (p <0.05). PTC is associated with a significant incidence of occult central and lateral nodal metastases. In patients undergoing prophylactic central neck dissection, inclusion of level 3 dissection should be considered in patients with large upper lobe cancers