What are the preoperative factors that can determine the presence of metastases in other axillary nodes in breast cancer when the sentinel node is positive?

AIM: To determine whether preoperative factors, such as size of metastases in the sentinel lymph node (SLN), number of positive SLNs (1, >1), tumoral grade, lymphovascular invasion (LVI) and tumoral size can predict the presence of metastases in non-SLNs, when the SLN is positive. METHODS: The study population was 1 146 breast cancer patients. Lymphadenectomy was performed in 150. Three groups of patients were established depending on the size of the metastases in SLNs: group A: <2 mm; group B: 2 < or =GC < or =5 mm; group C: > 5 mm. Either the chi(2) test or Fisher's test was performed to compare categorical variables, and a multivariate conditional logistic regression model for data sets was performed to identify the deterministic factors of metastases presence. RESULTS: Ten percent of group A, 28% of group B and 52% of group C presented non-SLN metastases. Patients with >1 positive-SLN presented significantly more non-SLN metastases than those with only one positive-SLN; 56% of patients with LVI presented non-SLN metastases versus 26% of those without LVI. The tumoral grade and size did not seem to have any influence on the number of patients with non-SLN metastases. The number of positive-SLNs and size of metastases were statistically associated with the presence of metastases. CONCLUSIONS: In this study population, the probability of finding non-SLN metastases was statistically related to the size of the SLN metastases and the number of positive-SLNs.

[Lymphoscintigraphy and sentinel node biopsy in non-palpable breast cancer]. / Linfogammagrafía y biopsia del ganglio centinela en el carcinoma no palpable de mama.

OBJECTIVE: The aim of the study was to evaluate the efficacy of lymphatic mapping and sentinel node biopsy in non-palpable breast cancer (NPBC) patients in comparison with palpable breast cancer (PBC) patients. MATERIAL AND METHODS: 199 breast cancer patients were studied. Patients were classified into two groups: NPBC and PBC. Following sentinel node biopsy all patients underwent axillary lymphadenectomy. Surgery was performed at 4-24 h after peritumoral injection of 111MBq 99mTc-nanocolloid. Histological sentinel node analysis was performed by cytological imprinting and delayed study. The following parameters were analyzed in both groups: scintigraphic and surgical detection rates, true positives (TP), true negatives (TN), sensitivity (S), predictive negative value (PNV), false negative rate (FNR) and global precision (GP) of the technique. RESULTS: No significant differences were observed (p > 0.05) in either the lymphoscintigraphy or surgical sentinel node detection, or drainage to internal mammary chain (p = 0.211) in both groups. Metastatic axillary prevalence was lower in NPBC group (p = 0.019). Similar S, NPV and GP values (>90 %) and FNR (< or = 6 %) were found in both groups. CONCLUSIONS: The reliability of the technique is similar in both groups. Drainage is predominantly axilar. Drainage to internal mammary chain was more frequently seen in medial tumours and in NPBC. Metastatic axillary prevalence was lower in the NPBC group.

Subdermal re-injection: a method to increase surgical detection of the sentinel node in breast cancer without increasing the false-negative rate.

PURPOSE: The aim of this study was to evaluate in breast cancer whether subdermal (SB) re-injection improves surgical detection (SD) of the sentinel node (SN) in patients with negative lymphoscintigraphy on peritumoral (PT) injection, without increasing the false-negative (FN) rate. METHODS: Group I comprised 261 patients with invasive breast cancer >3 cm and clinically negative axilla treated with primary chemotherapy. Axillary lymphadenectomy was performed in all of these patients. Group IA comprised 201 patients with PT injection, while group IB comprised 60 patients with SB injection in the tumour quadrant. Group II comprised 652 patients with breast cancer <3 cm; in 73 of these patients with negative lymphoscintigraphy, SB re-injection was performed. For lymphoscintigraphy, 37-55 MBq (99m)Tc-albumin nanocolloid in 1 ml was used for PT injection, and 18 MBq in 0.2 ml for SB injection. Five-minute images were obtained 2 h p.i. for PT injection and 20-30 min p.i. for SB injection. SD was performed 4 or 24 h p.i. Lymphoscintigraphic (LD), surgical and internal mammary (IM) detection rates were calculated. In group I, FN, negative predictive value (NPV) and accuracy (A) were calculated. Statistical analysis was performed using the chi-square test. RESULTS: In percentages, results were as follows: Group IA: SD: 84.1, FN: 13.6, NPV: 88.9, A: 78.6, IM: 14.5*. Group IB: SD: 90, FN: 0, NPV: 100, A: 90, IM: 1.7* (*p<0.025). Group II: PT injection only: LD: 82.4, SD: 94; PT injection+SB re-injection: LD: 90, SD: 98.5. SD was 97.8** in patients with positive lymphoscintigraphy and 58.5** when lymphoscintigraphy was negative (**p<0.001). CONCLUSION: For correct staging, including extra-axillary drainage, peritumoural injection should first be performed. When the SN is not visualised, and only in those cases, SB re-injection should be performed, which increases the SD rate without increasing the FN rate.