Is dissection of the internerve tissue during axillary lymphadenectomy for breast cancer necessary?

Interneural tissue clearance in axillary dissection for breast cancer: What is the importance?

BACKGROUND

Breast cancer is the most common cancer in women and second most common type of cancer overall. The prime objectives of axillary surgery in the management of breast cancer are 1) accurate staging, 2) treatment to cure and 3) quantitative information of metastatic lymph nodes for prognostic purposes and allocation to adjuvant protocols. During axillary dissection, all 3 level lymphnodes are removed, while the important axillary structures (axillary vein, long thoracic and thoracodorsal nerves) are preserved. The latter two structures are particularly vulnerable to injury when dissecting the tissue between them (the interneural tissue).

METHODS

This prospective non-randomized study, conducted on 125 female patients, who underwent axillary lymphadenectomy for breast cancer has evaluated the importance of dissection of the Interneural tissue during axillary dissection in breast cancer surgery by reviewing the lymph node yield and metastasis rate. The interneural tissue was excised separately after a routine axillary dissection.

RESULTS

Lymph nodes were found in the interneural tissue of 70 out of 125 patients (56%). The average number of interneural lymph nodes recovered per specimen was 1.3. The interneural tissue lymph nodes were positive for metastasis in 10 (8%) patients. There was no incidence of isolated metastasis in the internerve tissue nodes.

CONCLUSIONS

There is a significant incidence of lymph nodes (56%) and axillary node metastases (8%) in the tissue lying between the long thoracic and thoracodorsal nerves. Therefore, meticulous dissection and excision of this interneural tissue is strongly recommended to optimize decision making regarding adjuvant treatment and outcome.

Scapula alata in early breast cancer patients enrolled in a randomized clinical trial of post-surgery short-course image-guided radiotherapy

BACKGROUND

Scapula alata (SA) is a known complication of breast surgery associated with palsy of the serratus anterior, but it is seldom mentioned. We evaluated the risk factors associated with SA and the relationship of SA with ipsilateral shoulder/arm morbidity in a series of patients enrolled in a trial of post-surgery radiotherapy (RT).

METHODS

The trial randomized women with completely resected stage I-II breast cancer to short-course image-guided RT, versus conventional RT. SA, arm volume and shoulder-arm mobility were measured prior to RT and at one to three months post-RT. Shoulder/arm morbidities were computed as a post-RT percentage change relative to pre-RT measurements.

RESULTS

Of 119 evaluable patients, 13 (= 10.9%) had pre-RT SA. Age younger than 50 years old, a body mass index less than 25 kg/m2, and axillary lymph node dissection were significant risk factors, with odds ratios of 4.8 (P = 0.009), 6.1 (P = 0.016), and 6.1 (P = 0.005), respectively. Randomization group was not significant. At one to three months' post-RT, mean arm volume increased by 4.1% (P = 0.036) and abduction decreased by 8.6% (P = 0.046) among SA patients, but not among non-SA patients. SA resolved in eight, persisted in five, and appeared in one patient.

CONCLUSION

The relationship of SA with lower body mass index suggests that SA might have been underestimated in overweight patients. Despite apparent resolution of SA in most patients, pre-RT SA portended an increased risk of shoulder/arm morbidity. We argue that SA warrants further investigation. Incidentally, the observation of SA occurring after RT in one patient represents the second case of post-RT SA reported in the literature.