Reconstitution of alternative routes of drainage from the lymph nodes may lead to the undesired result of additional and previously unaffected nodes receiving primary drainage from the vicinity of the cancer-infected breast. Unpredicted alternative lymphatic pathways might be prompted by radiotherapy or previous operations could lead to damage to the usual draining lymphatics[
14‐
16]. The high identification rate of altered lymphatic drainage in our series is attributed to previous ALND and radiotherapy (one of seven patients had ALND plus radiotherapy, one patient ALND and one patient axillary radiotherapy). There is clearly a necessity to conduct a second lymphatic mapping injection and lymphoscintigraphy before SLNB. Even patients with a virgin axilla will not have easy-to-predict patterns of drainage, and there is a greater possibility of locating nodes outside the ipsilateral axilla among patients who have underwent a previous axillary operation[
17‐
21].
Haagensen
et al. hypothesized that, by permeating the deep lymphatic plexus of the wall of the chest, tumor cells might disperse to the contralateral axillary[
22]. In the present study, two out of 330 (0.6%) consecutive patients were identified with contralateral axillary drainage on lymphoscintigraphy. A contralateral SLN biopsy was attempted in both patients; only one of the two patients who had a contralateral axillary SLN proved to be positive for a tumor. The second patient also had an ipsilateral SLN, and both ipsilateral and contralateral SLNBs showed no metastatic involvement. There has been no ipsilateral or contralateral axillary recurrence (mean 54 months) following a negative SLNB in these patients. Contralateral axillary lymph node metastases are generally associated with the aggressiveness of the primary tumor’s pathology. Morcos
et al. Compared data for 401 breast cancer patients who did not have contralateral axillary lymph node metastases with that of 21 patients with contralateral axillary lymph node metastases. Their retrospective analysis showed that tumor grade, lymphovascular invasion, tumor size, hormone receptor negativity and HER2 overexpression increases the risk of contralateral axillary metastases[
23]. In our series, the patient with contralateral metastases had grade 2 invasive ductal carcinoma, T2, ER-PR receptor positive, and HER2 negative. As seen in our series, the histopathological features of the tumor in this patient with contralateral axillary metastasis were not aggressive. In comparison, the findings for this patient drive attention to the range of different etiologies that might have caused contralateral axillary drainage and altered the metastases area. Contralateral axillary metastases have been regarded as a distant metastatic disease, and therefore it was suggested to be treated with systemic therapy (either hormonal or chemotherapy). Emerging data indicate, that rather than a hematogeneous metastasis, the alteration of lymphatic drainage might have the pivotal role in the contralateral axillary lymphatic metastases, to this area. In addition, rarely native breast and axilla might have alternated lymphatic drainage and should be determined. As many studies show, contralateral axillary metastases and primary breast cancer could be discovered either at the same time or after having received treatment for recurring breast cancer[
21‐
24]. Although more data needs to be gathered, a treatment approach for patients who have contralateral axillary metastasis without distant metastases should be curative in intent.
Therefore, synchronous or metachronous contralateral axillary lymph nodes without systemic metastases could be thought of as a curative disease due to the fact that they are dispersalis lymphogenic and not hematogenous. Despite a lack of consensus, patients seek this type of treatment in the hope of being cured[
23‐
28].
There is great optimism within the scientific literature about the reliability of the capacity of re-operative SLNB to determine whether or not there are axillary nodes that test positive for metastasis[
29‐
36]. Positive SLNs were discovered in one out of seven (14.2%) patients of our series (Table
1). After a mean 27-month follow-up period, no local axillary recurrences have been found in any patients.