Prediction of axillary lymph node metastases in a screened breast cancer population. South-East Sweden Breast Cancer Group

Assessment of the axilla in women with early-stage breast cancer undergoing primary surgery: a review

Sentinel node biopsy (SNB) is routinely performed in people with node-negative early breast cancer to assess the axilla. SNB has no proven therapeutic benefit. Nodal status information obtained from SNB helps in prognostication and can influence adjuvant systemic and locoregional treatment choices. However, the redundancy of the nodal status information is becoming increasingly apparent. The accuracy of radiological assessment of the axilla, combined with the strong influence of tumour biology on systemic and locoregional therapy requirements, has prompted many to consider alternative options for SNB. SNB contributes significantly to decreased quality of life in early breast cancer patients. Substantial improvements in workflow and cost could accrue by removing SNB from early breast cancer treatment. We review the current viewpoints and ideas for alternative options for assessing and managing a clinically negative axilla in patients with early breast cancer (EBC). Omitting SNB in selected cases or replacing SNB with a non-invasive predictive model appear to be viable options based on current literature.

Axillary management for early invasive breast cancer patients: Who will truly benefit?

Background

The implementation of sentinel lymph node biopsy (SLNB) and further completion axillary lymph node dissection (cALND) after positive sentinel lymph nodes (SLNs) on early invasive breast cancer patients should be cautiously tailored. Identifying predictors for SLN and non-sentinel lymph node (nSLN) metastases can help surgeons make better surgical decisions.

Methods

A retrospective case-control study was designed and a total of 560 eligible patients were enrolled consecutively. They were all diagnosed in our center and received appropriate medical care. According to the metastasis of SLN and nSLN, they were divided into metastatic and non-metastatic groups on two successive occasions to investigate the relationship between clinical factors, pathological factors, hematological factors and lymph node metastasis.

Results

In total, 101 (18.04%) patients developed SLN metastases, including 98 patients with macro-metastases and 3 patients with micro-metastases. Out of 97 patients receiving further cALND, 20 patients (20.62%) developed nSLN metastases. Multivariate analysis revealed that “high expression of Ki-67” and “lymphatic invasion” predicted a higher risk of SLN metastasis; and “increased number of positive SLNs” and “increased systemic inflammation index (SII)” predicted a higher risk of nSLN metastasis.

Conclusion

Surgery for early invasive breast cancer patients should be more customized and precise. Appropriate axillary management is necessary for patients with the associated predictors.

Peritumoral immune infiltrates in primary tumours are not associated with the presence of axillary lymph node metastasis in breast cancer: a retrospective cohort study

Background

The axillary lymph nodes (ALNs) in breast cancer patients are the body regions to where tumoral cells most often first disseminate. The tumour immune response is important for breast cancer patient outcome, and some studies have evaluated its involvement in ALN metastasis development. Most studies have focused on the intratumoral immune response, but very few have evaluated the peritumoral immune response. The aim of the present article is to evaluate the immune infiltrates of the peritumoral area and their association with the presence of ALN metastases.

Methods

The concentration of 11 immune markers in the peritumoral areas was studied in 149 patients diagnosed with invasive breast carcinoma of no special type (half of whom had ALN metastasis at diagnosis) using tissue microarrays, immunohistochemistry and digital image analysis procedures. The differences in the concentration of the immune response of peritumoral areas between patients diagnosed with and without metastasis in their ALNs were evaluated. A multivariate logistic regression model was developed to identify the clinical-pathological variables and the peritumoral immune markers independently associated with having or not having ALN metastases at diagnosis.

Results

No statistically significant differences were found in the concentrations of the 11 immune markers between patients diagnosed with or without ALN metastases. Patients with metastases in their ALNs had a higher histological grade, more lymphovascular and perineural invasion and larger-diameter tumours. The multivariate analysis, after validation by bootstrap simulation, revealed that only tumour diameter (OR = 1.04; 95% CI [1.00–1.07]; p = 0.026), lymphovascular invasion (OR = 25.42; 95% CI [9.57–67.55]; p < 0.001) and histological grades 2 (OR = 3.84; 95% CI [1.11–13.28]; p = 0.033) and 3 (OR = 5.18; 95% CI [1.40–19.17]; p = 0.014) were associated with the presence of ALN metastases at diagnosis. This study is one of the first to study the association of the peritumoral immune response with ALN metastasis. We did not find any association of peritumoral immune infiltrates with the presence of ALN metastasis. Nevertheless, this does not rule out the possibility that other peritumoral immune populations are associated with ALN metastasis. This matter needs to be examined in greater depth, broadening the types of peritumoral immune cells studied, and including new peritumoral areas, such as the germinal centres of the peritumoral tertiary lymphoid structures found in extensively infiltrated neoplastic lesions.

Long-term outcome of pT1a-b, cN0 breast cancer without axillary dissection or staging: a prospective observational study of 1543 women

BACKGROUND

The implementation of screening programmes in Sweden during the mid-1990s increased the number of small node-negative breast cancers. In this era before staging by sentinel node biopsy, routine axillary dissection for staging of early breast cancer was questioned owing to the increased morbidity and lack of perceived benefit. The long-term risk of axillary recurrence when axillary staging is omitted remains unclear.

METHODS

This prospective observational multicentre cohort study included Swedish women diagnosed with breast cancer between 1997 and 2002. The patients had clinically node-negative, pT1a-b, grade I-II tumours. No axillary staging or dissection was performed. The primary outcome was ipsilateral axillary recurrence and survival.

RESULTS

A total of 1543 patients were included. Breast-conserving surgery (BCS) was performed in 94·0 per cent and the rest underwent mastectomy. After surgery, 58·1 per cent of the women received adjuvant radiotherapy, 11·9 per cent adjuvant endocrine therapy and 31·5 per cent did not receive any adjuvant treatment. After a median follow-up of 15·5 years, 6·4 per cent developed contralateral breast cancer and 16·5 per cent experienced a recurrence. The first recurrence was local in 116, regional in 47 and distant in 59 patients. The breast cancer-specific survival rate was 93·7 per cent after 15 years. There were no differences in overall or breast cancer-specific survival between patients who received adjuvant radiotherapy and those who did not. Only 3·0 per cent of patients had an axillary recurrence, which was isolated in only 1·0 per cent.

CONCLUSION

Axillary surgery can safely be omitted in patients with low-grade, T1a-b, cN0 breast cancers. This large prospective cohort with 15-year follow-up had a very low incidence of axillary recurrences and high breast cancer-specific survival rate.

Transpectoral Anterior Approach to the Axilla for Lymph Node Dissection in Association with Mastectomy Preserving Both Pectoral Muscles and Their Neurovascular Bundles

In Patey's mastectomy, which is still the most common operation for breast cancer, axillary node dissection (AND) is performed through the base of the axilla after retracting the pectoralis major muscle and excising the pectoralis minor muscle (some surgeons preserve the latter). This has the disadvantage of inadequate exposure of the axilla and the risk of damage to the neurovascular bundles supplying the pectoral muscles, which in the long run may lead to atrophy of these muscles. A transpectoral anterior approach to the axilla for AND in association with mastectomy was attempted in 115 cases to obviate the above-mentioned disadvantages. The approach included: 1) splitting of the pectoralis major between the clavicular and sternal fibers; 2) mobilization and swinging of the pectoralis minor into different directions by means of a sling to facilitate AND at selected levels. The major advantages of this approach were: 1) total preservation of both pectoral muscles with their neurovascular bundles maintained the normal anatomy and function of the shoulder; 2) the axilla was directly approached through the anterior wall instead of through the base; in this way the axillary contents were exposed almost at surface level; 3) the dissection plane could be limited to anterior to and below the axillary vein and the risk of postoperative lymphedema could thus be minimized; 4) change of position of the ipsilateral arm was not necessary; 5) the duration of surgery was reduced. Monoblock ablation of significant and suspected tissues, maintaining the normal anatomy and function of the shoulder, could be easily accomplished with this approach.

Diagnostic Accuracy and Impact on Management of Ultrasonography-Guided Fine-Needle Aspiration to Detect Axillary Metastasis in Breast Cancer Patients: A Prospective Study

BACKGROUND

The axillary nodal status is essential to determine the stage of disease at diagnosis. Our aim was to prospectively assess the diagnostic accuracy of ultrasonography-guided fine-needle aspiration (US-FNA) for the detection of metastasis in axillary lymph nodes in patients with breast cancer (BC) and its impact on the therapeutic decision.

MATERIALS AND METHODS

Ultrasonography (US) was performed in 407 axillae of 396 patients who subsequently underwent surgery. US-FNA was conducted when lymph nodes were detected by US. Axillary dissection (AD) was performed when US-FNA was positive for metastasis. Patients with negative US-FNA and breast tumors of 30 mm in size were candidates for selective sentinel lymph node biopsy (SLNB). The anatomopathological results of AD or SLNB were used as reference tests.

RESULTS

Lymph nodes were detected by US in 207 (50.8%) axillae. Of these, US-FNA was performed on 180 (86.9%). 94 axillae (52.2%) were positive for carcinoma and 79 women received AD. US-FNA had 77.5% sensitivity, 100% specificity, 100% positive predictive value, 69.3% negative predictive value, and 85.1% diagnostic accuracy. US-FNA avoided SLNB in 18.1% of patients who underwent AD.

CONCLUSIONS

Axillary US-FNA is an accurate technique in the staging of patients with BC. It allows reducing the number of SLNB and, when positive, offers a fast and useful tool.

Predictive role of tumor size in breast cancer with axillary lymph node involvement - can size of primary tumor be used to omit an unnecessary axillary lymph node dissection?

BACKGROUND

Breast cancer is the most common cancer among women worldwide. The aim of this study was to investigate the relationship between tumor size and axillary lymph node involvement (ALNI) in patients with invasive lesions, to find the best candidates for a full axillary dissection. Additionally, we evaluated the association between tumor size and invasive behavior. The study was based on data from 789 patients with histopathologically proven invasive breast cancer diagnosed in Shohada University hospital in Tehran, Iran (1993-2009). Cinical and histopathological characteristics of tumors were collected. Patients were divided into 6 groups according to primary tumor size: group I (0.1-≤1cm), II (1.1-≤2cm), III (2.1-≤3cm), IV (3.1-≤4cm), V (4.1-≤5cm) and VI (>5cm). The mean(±SD) size of primary tumor at the time of diagnosis was 3.59±2.69 cm that gradually declined during the course of study. There was a significant correlation between tumor size and ALNI (p<0.001). A significant positive correlation between primary tumor size and involvement of surrounding tissue was also found (p<0.001). The mean number of LNI in group VI was significantly higher than other groups (p<0.05).We observed more involvement of lymph nodes, blood vessels, skin and areola-nipple tissue with increase in tumor size.We found 15.3% overall incidence of ALNI in tumors ≤2 cm, indicating the need for more investigation to omit full axillary lymph node dissection with an acceptable risk for tumors below this diameter. While in patients with tumors ≥2 cm, 84.3% of them had nodal metastases, so the best management for this group would be a full ALND. Tumor size is a significant predictor of ALNM and involvement of surrounding tissue, so that an exact estimation of the size of primary tumor is necessary prior to surgery to make the best decision for management of patients with invasive breast cancer.

Predictors of axillary lymph node metastases in early breast cancer and their applicability in clinical practice

PURPOSE

Lymph node involvement is the most important prognostic factor in breast cancer. It is a multifactorial event determined by patient and tumour characteristics. The purpose of this study was to determine clinical and pathological factors predictive for axillary lymph node metastasis (ALNM) in patients with early breast cancer and to build a model to portend lymph node involvement.

METHODS

We evaluated 1300 consecutive patients surgically treated in our institution (2007-2009) for cT1-T2 invasive breast cancer. The patient and tumour characteristics evaluated included: age at diagnosis, number of foci, histologic grade, location, tumour size, histologic subtype, lymphovascular invasion (LVI), estrogen-receptor (ER), progesterone-receptor (PR) and Her-2 status. Univariate and multivariate analyses were performed. Factors significantly associated with ALNM by univariate analysis plus histologic subtype were included in the multivariate analysis.

RESULTS

By univariate analysis, the incidence of ALNM was significantly associated with the presence of LVI (P < 0.0001), larger tumour size (P < 0.0001), higher histologic grade (P < 0.0001), retroareolar or lateral location in the breast (P < 0.0001), multiple foci (P = 0.0002) and in patients who underwent an axillary lymph node dissection. We found no effect of age, ER⁄PR nor HER-2 status. By multivariate analysis, ALNM was significantly associated with the presence of LVI (P < 0.0001), larger tumour size (P < 0.0001), axillary lymph node dissection (P = 0.0003), retroareolar and lateral tumour location in the breast (P = 0.0019) and the presence of multiple foci (P = 0.0155).

CONCLUSIONS

LVI and tumour size emerged as the most powerful independent predictors of ALNM, followed by the location of the tumour in the breast and the presence of multiple foci.

Factors predicting the axillary lymph node metastasis in breast cancer: is axillary node clearance indicated in every breast cancer patient?: factors predicting the axillary lymphnode metastases in breast cancer

The study was carried out to find out predictors of axillary lymph node metastasis in breast cancer and to evaluate its significance in selecting the group of patients in whom axillary dissection could be avoided. Ninety-five breast cancer patients who underwent mastectomy and axillary dissection were included in the study. Factors like patient's age, tumor size, histopathological type, histological grade and estrogen and progesterone receptor status were correlated with the axillary metastases. Out of 95 cases axillary metastasis was found in 47 (49.47%) cases. There was no correlation between patient's age and tumor size with axillary metastasis (p > 0.05). Based on histopathological typing tumors like ductal carcinoma in situ, tubular carcinoma and mucinous carcinoma showed less tendency for axillary metastasis (p < 0.046). Association was found between histological grade and estrogen receptor and progesterone receptor positivity with presence of axillary metastasis (p < 0.001 and 0.002 respectively). The findings in this study indicate that breast cancer patients having favorable histological type, grade I tumors and estrogen and progesterone receptor negative tumor are good candidates to avoid axillary dissection.

A decision tool for predicting sentinel node accuracy from breast tumor size and grade

The ability to predict axillary lymph node involvement in breast cancer patients in the preoperative setting is invaluable. This study provides a simple set of formulae to enable clinicians to make informed decisions in the management of screen-detected breast cancer. The tumor pathology reports were obtained of all 4,585 women identified between 1996 and 1999 in New South Wales (NSW) with T1 or T2 breast cancer by the statewide co-ordinated breast screening service (BreastScreen NSW). Equations predicting node positivity were calculated by linear regression analysis and, from published sentinel node false-negative rates, the probability of retrieval of a false-negative axillary lymph node by sentinel node biopsy was calculated for tumors of different size and grade. Node involvement was identified in 1,089 (23.8%) of women. A linear relationship for tumor size, grade, and nodal involvement was predicted by: frequency (%) = 1.5 x tumor size (mm) + 2 (or 6 or 10) for grade I (or II or III) tumors. Assuming a 7.5% false-negative rate, the probability of retrieving a false-negative sentinel node ranged from 0.8% for a patient with a 5 mm, grade I carcinoma to 6.0% for a 50 mm, grade III tumor. These simple formulae are easy to use in a clinical setting. The reference table enables breast surgeons to inform a patient about the absolute probability of false-negative sentinel biopsy rates for patients with screen-detected carcinomas when size can be estimated from preoperative imaging and when tumor grade is often available from preoperative core biopsy. Patients with large, T2 breast tumors may be best treated with axillary dissection rather than sentinel node biopsy alone due to the risk of under-staging the woman's disease and also the high probability of finding a positive sentinel node.

Predictors of axillary lymph node metastasis in breast cancer: A systematic review

AIMS

To review the established and emerging techniques in axillary lymph node prediction and explore their potential impact on clinical practice. To reliably identify patients in whom axillary lymph node surgery, including SLNB, can be safely omitted.

METHODS

Searches of PubMed were made using the search terms "axilla" (or "axillary"), "lymph", "node" and "predictor" (or "prediction"). Articles from abstracts and reports from meetings were included only when they related directly to previously published work.

FINDINGS

There are numerous studies in which the predictive utility of biomarkers as determinants of axillary lymph node status have been investigated. Few of these have specifically addressed the attributes of the primary tumour which could offer much potential for the prediction of tumour metastasis to the axillary lymph nodes.

CONCLUSIONS

Currently, no single marker is sufficiently accurate to obviate the need for formal axillary staging using SLNB or axillary clearance.

Probability of axillary lymph node metastasis when sentinel lymph node biopsy is negative in women with clinically node negative breast cancer: a Bayesian approach

BACKGROUND

Although sentinel lymph node biopsy(SLNB)is highly accurate in predicting axillary nodal status in patients with breast cancer, it has been shown that the procedure is associated with a few false negative results. The risk of leaving metastatic nodes behind in the axillary basin when SLNB is negative should be estimated for an individual patient if SLNB is performed to avoid conventional axillary lymph node dissection(ALND).

METHODS

A retrospective analysis of 512 women with T1-3N0M0 breast cancer was conducted to derive a prevalence of nodal metastasis by T category as a pre-test(i.e., before SLNB)probability and to examine potential confounders on the relationship between T category and axillary nodal involvement. Probability of nodal metastasis when SLNB was negative was estimated by means of Bayes' theorem which incorporated the pre-test probability and sensitivity and specificity of SLNB.

RESULTS

Axillary nodal metastasis was observed in 6.1% of T1a-b, 25.1% of T1c, 28.7% of T2, 35.0% of T3 tumors. Point estimates for the probability of nodal involvement when SLNB was negative ranged from 0.3-1.3% for T1a-b, 1.6-6.3% for T1c, 2.0-7.5% for T2, and 2.6-9.7% for T3 tumors with representative sensitivities of 80%, 85%, 90% and 95%, respectively. The risk may be higher when the tumor involves the upper outer quadrant of the breast, while it may be lower for an underweight woman.

CONCLUSIONS

The probability of axillary lymph node metastasis when SLNB is negative can be estimated using a Bayesian approach. Presenting the probability to the patient may guide the decision of surgery without conventional ALND.

Predicting the status of axillary sentinel lymph nodes in 4351 patients with invasive breast carcinoma treated in a single institution

BACKGROUND

Reliable predictors of metastatic involvement would enable a better selection of candidate patients for sentinel lymph node biopsy (SLNB) and possibly allow identification of patients with such a low risk of axillary sentinel lymph node (SLN) involvement to be even spared SLNB.

METHODS

The authors evaluated 4351 consecutive patients surgically treated for breast carcinoma who also underwent SLNB. Clinicopathologic features significantly associated with SLN metastases by univariate analysis were included in a multivariate model.

RESULTS

By multivariate analysis, the prevalence of SLN metastases was associated directly with tumor size, multifocality, and with the occurrence of peritumoral vascular invasion (PVI; all P < 0.0001), and was associated inversely with a favorable histotype (P = 0.0007) and lack of progesterone receptors (P = 0.004). A predictive model based on the features more closely associated with SLN status documented that the patients with a favorable tumor type </= 1 cm in size and without PVI (n = 178 [4% of the population]) had the lowest risk of SLN metastases (9.5%) whereas patients with tumors > 2 cm and with PVI (n = 250 [5.7% of the population]) had the highest risk (77.2%) of SLN involvement.

CONCLUSIONS

Tumor size and PVI emerged as the most powerful independent predictors of SLN metastases. Although no combination of features identified patients with a < 9.5% risk of SLN metastases, the current data may be used to tailor the management of patients with breast carcinoma with the aim of minimizing as much as possible the diagnostic and therapeutic procedures, thus improving the quality of life of the patients without any adverse effect on their survival rates.

Will we need lymph node dissection at all in the future?

Traditionally in the treatment of primary breast cancer, axillary lymph node dissection (ALND) plays an important role. However, a substantial and increasing percentage of patients appear to have no nodal involvement and have been subjected to ALND unnecessarily. The first reason to perform an ALND is axillary nodal staging. After reviewing the literature, it can be concluded that in clinically node-negative patients an adequately conducted lymphatic mapping by sentinel node procedure is equal to ALND for this purpose. The second reason to perform an ALND is to establish the extent of nodal involvement, which might have an impact on adjuvant treatment recommendations. However, there is no evidence available that patients with extensive nodal involvement (= 4 positive nodes) benefit more from adjuvant systemic treatment (either standard or high dose) in terms of reduction of odds of recurrence and mortality compared to patients with limited nodal involvement and optimally administered so-called standard adjuvant treatment. The third reason to perform an ALND is to ensure axillary tumor control. Reviewing the different treatment options, it can be concluded that in clinically node-negative patients axillary control after axillary radiotherapy appears to be similar to axillary control after ALND. In clinically overt axillary involvement, ALND (with or without adjuvant radiotherapy) may result in an improved regional control. In the near future, ALND will not be the standard of care but will be reserved for those patients with proven axillary lymph node involvement. In microscopic disease, radiotherapy may be an alternative with equal control and less morbidity.

A prospective validated model for predicting axillary node metastases based on 2,000 sentinel node procedures: the role of tumour location [corrected]

AIMS

The purpose was to identify the independent predictive factors of axillary lymph-node metastases (ALNM) in infiltrating ductal carcinoma (IFDC) and to create a prospective, validated statistical model to predict the likelihood of ALNM in patients in the present era of sentinel lymph-node (SLN) biopsy and enhanced histopathology.

METHODS

Univariate and multivariate analyses of 13 clinicopathological variables (including tumour location) were performed to determine predictors of ALNM in 1659 eligible SLN biopsy procedures. A logistic regression model was developed and then prospectively validated on a second population of 187 subsequent consecutive procedures.

RESULTS

Age, pathological tumour size, palpability, lymphovascular invasion (LVI), histological grade, nuclear grade, ductal histological subtype, tumour location (quadrant) and multifocality were associated with ALNM in univariate analyses (P < 0.001). Of these, only palpability and histological grade were not statistically associated with ALNM in the multivariate analysis (P> 0.05). The frequency of ALNM in upper-inner-quadrant (UIQ) tumours was 20.6%, compared with 33.2% for all other quadrants (P<0.0005). There was no statistical difference between UIQ and other-quadrant tumours in any clinicopathological variables analysed. The logistic regression model, developed based on the population of 1659, had the same accuracy, sensitivity, specificity, positive predictive value and negative predictive value when applied prospectively to the second population.

CONCLUSION

Tumour size, LVI, age, nuclear grade, histological subtype, multifocality and location in the breast were independent predictive factors for ALNM in IFDC. ALNM is less frequent in UIQ tumours than in other-quadrant tumours. Our prospectively validated predictive model could be valuable in pre-operative patient discussions, although staging of the axilla in the individual patient remains necessary.

Frequency and predictors of axillary lymph node metastases in invasive breast cancer

BACKGROUND

The objectives of the present study were to evaluate the incidence and predictors of axillary lymph node metastases (ALNM) in patients with breast cancer, and to identify if axillary surgery could be safely omitted in selected patients.

METHODS

Between January 1996 and May 2000, 492 patients underwent 501 axillary lymph node dissections (ALND). The incidence of ALNM was correlated with clinical and pathological characteristics by univariate and multivariate analyses.

RESULTS

Axillary lymph node metastases were found in 41% (207/501) of cases. Univariate analysis showed that palpability of primary and axillary lymph node (ALN), pathological tumour size, grade, lymphovascular invasion (LVI) and multifocality or multicentricity were significant predictors of ALNM. By multivariate analysis, palpability of ALN, pathological tumour size, LVI and multifocality or multicentricity remained as independent predictors. Among the 431 cases without palpable ALN, no ALNM were found if the tumour was < or = 5 mm, non-multifocal or multicentric, and without LVI, or the tumour was a tubular or mucinous carcinoma < or = 15 mm (n = 21). The frequency of ALNM in the absence of the other risk factors was 11% (7/64) if the tumour size was > 5-10 mm, and 17% (19/113) if the tumour was > 10-20 mm. However, the incidence of ALNM was 72% for the 32 clinically node-negative cases with multifocal or multicentric tumour > or = 10 mm and LVI. Those patients with palpable ALN (n = 66) had a greater than 50% risk of ALNM.

CONCLUSIONS

Routine ALND could be omitted in clinically node-negative patients with either a < or = 5-mm, LVI-negative tumour, or a < or = 15-mm tubular or mucinous carcinoma. Axillary lymph node dissection is still useful for determining pathological nodal status in all other cases, and in most cases with palpable ALN, as a therapeutic manoeuvre.

The risk of nodal metastases in breast cancer patients with clinically negative lymph nodes: a population-based analysis

A population-based study was performed to assess the likelihood of axillary lymph node metastases in patients with clinically negative lymph nodes, according to patient age, tumor size and site, estrogen receptor status, histologic type and mode of detection. Data were obtained from the population-based Eindhoven Cancer Registry. During the period 1984-1997, 7680 patients with invasive breast cancer were documented, 6663 of whom underwent axillary dissection. Of the 5125 patients who were known to have clinically negative lymph nodes and underwent axillary dissection, 1748 (34%) had positive lymph nodes at pathological examination. After multivariate analysis, histologic type, tumor size, tumor site and the number of lymph nodes in the axillary specimen remained as independent predictors of the risk of nodal involvement (P < 0.001). Lower risks were found for patients with medullary or tubular carcinoma, smaller tumors, a tumor in the medial part of the breast and patients with less than 16 nodes examined. This study gives reliable estimates of the risk of finding positive lymph nodes in patients with a clinically negative axilla. Such information is useful when considering the need for axillary dissection and to predict the risk of a false-negative result when performing sentinel lymph node biopsy.

Factors associated with axillary lymph node metastasis from breast carcinoma: descriptive and predictive analyses

BACKGROUND

Although axillary lymph node metastasis is one of the most important prognostic determinants of breast carcinoma prognoses, the reasons why tumors vary in their capability to produce for axillary metastases remain unclear.

METHODS

The authors used data from the nationwide Patient Care Evaluation (PCE) survey of the American College of Surgeons to evaluate the correlations between patient/tumor characteristics and lymph node status, and to explore the use of these factors, which are all known prior to axillary dissection, in predicting lymph node status. The PCE data set contained 18,025 breast carcinoma cases diagnosed in 1990 after exclusion of women older than 79 years or with fewer than 6 lymph nodes examined.

RESULTS

In a multivariate logistic regression model, larger tumor size, young age, African American or Hispanic race, outer half tumor location, poor or moderate differentiation, aneuploidy, and infiltrating ductal histology were independently associated with a higher likelihood of one or more positive lymph nodes. Contrary to expectation, cases negative for estrogen receptor (ER) and progesterone receptor (PR) had a lower risk of positive lymph nodes when adjusted for other factors (odds ratio = 0.82; 95% confidence interval: 0.74-0.91) compared with cases positive for both receptors. This model accurately predicted lymph node status in 2 validation data sets (a 50% random sample of 1990 PCE data and 1992 data from the National Cancer Data Base), but was less accurate in a third, older data set (1983 PCE data). However, the percentage of cases (1990 validation set) with predicted probabilities less than 0.05 or greater than 0.95 were only 4.6% and <0.1%, respectively.

CONCLUSIONS

The authors concluded that 1) most variation in axillary lymph node metastatic status can be explained by routinely available data, 2) ER and PR status may be involved in the mechanism of this behavior, and 3) the difficulty of using prediction models to avert axillary dissection should not be underestimated.

Predictors of axillary lymph node metastases in patients with invasive breast carcinoma by a combination of classical and biological prognostic factors

The presence of axillary lymph node metastases (ALNMs) is the most important prognostic factor in breast carcinoma. If ALNMs were predictable without performing axillary lymph node dissection (ALND), this procedure would not be necessary in selected patients. Using a combination of some of the new biological markers with the classical ones, our objective was I) to identify the best set of predictors of ALNMs, and II) to define predictive models with either high or low probability of ALNMs. We studied 102 patients with invasive breast carcinoma. All patients underwent ALND, and at least 10 axillary lymph nodes per case were obtained. In the primary tumour we evaluated size, histological subtype and grade, lymphatic/vascular invasion and margin. Hormone receptor status, MIB1 index, microvessel density, c-erbB-2 and cathepsin D expression were assessed by immunohistochemistry, and DNA ploidy and S-phase by flow cytometry. Risk factors for ALNMs were estimated by nonlinear logistic regression analysis. The best predictors of ALNMs were: tumour size > 2 cm [OR 6.45, 95% confidence interval (CI) 21.74 to 1.91], presence of lymphatic/vascular invasion [OR 4.95, CI (14.50 to 1.69)], infiltrative margin [OR 9.87 CI (37.44 to 2.60)] and high MIB-1 index [OR 8.39, CI (33.47 to 2.10)]. Two subsets had a very high risk of ALNMs: I) tumour size > 2 cm, with lymphatic/vascular invasion and infiltrative margin; 26 (89.66%) of 29 patients of this subgroup had ALNMs, and (II) tumour size > 2 cm, with lymphatic/vascular and high MIB1 index.; eight of the nine (89%) patients of this subgroup had ALNMs. We could also identify a two-variable model with a very low risk of ALNMs constituted by tumour with circumscribed margin and low MIB-1 index. Of the 19 patients showing these features, only 1 (5.26%) had ALNMs. Therefore, pathological features of the primary tumour can help to assess the risk for ALNM in invasive breast carcinoma. Such risk assessment might avoid regional surgical overtreatment.

S-phase fraction and breast cancer--a decade of experience

During the past decade, more than 300 articles, abstracts, and book chapters have been published about S-phase fraction (SPF) determined by DNA flow cytometry and its clinical utility for patients with breast cancer. However, the use of SPF for making treatment decisions for breast cancer patients remains controversial. After reviewing 273 published articles, we conclude: 1) Despite different techniques and cutpoints, correlations between SPF and other prognostic markers are relatively consistent across studies; higher SPF is generally associated with worse tumor grade, absence of steroid receptors, larger tumors, and positive axillary lymph nodes. 2) Higher SPF is generally associated with worse disease-free and overall survival in both univariate and multivariate analyses; SPF values from laboratories that have conducted validation studies can be used, in combination with other factors, to estimate the prognosis of patients with primary breast cancer. 3) There is considerable variability among laboratories regarding assay methodology, cell-cycle analysis techniques, and cutpoints for classifying and interpreting SPF; use of SPF values from different laboratories is problematic, and there remains a need for standardization of these processes and well-designed confirmation studies. We conclude that measurement of SPF does have clinical utility for patients with breast cancer, but standardization and quality control must be improved before it can be routinely used in community settings.

Prognostic factors for patients with breast cancers 1cm and smaller

The widespread use of mammography has resulted in the detection of an increasing number of small invasive breast cancers, i.e. those that are 1cm and smaller. Patients with these small cancers generally have a low incidence of axillary lymph node metastases, and this has led some to question the routine use of axillary dissection in these patients. In addition, the prognosis of these patients is generally favorable, and the routine use of adjuvant systemic therapy is difficult to justify. Nonetheless, some patients with these small invasive cancers will have axillary nodal involvement and/or develop metastatic disease. The identification of this prognostically unfavorable subset of patients within this otherwise favorable group is an important goal of clinical research. In this article, we review the available literature on prognostic factors for patients with breast cancers 1cm and smaller to help determine which of these features might be of value in the identification of patients at risk for axillary lymph node involvement and/or metastatic disease.

Clinical observations of axillary involvement for tubular, lobular, and ductal carcinomas of the breast

BACKGROUND AND OBJECTIVES

Recently, there has been much interest in identifying primary breast cancer characteristics which have predictive value for axillary metastases. We studied breast cancer patients to determine variables associated with the incidence/extent of axillary involvement and to construct a modeled analysis.

METHODS

Patients with invasive ductal, lobular, and tubular breast cancer (group 1, n = 15,719) were analyzed by tumor size and histology for the probability/extent of axillary metastases. A subgroup of patients was analyzed separately for any association of axillary involvement and other variables (group 2).

RESULTS

In group 1, the incidence and extent (number of positive lymph nodes) of axillary metastases correlated significantly with histology and increasing tumor size of ductal and lobular histologies. Significant associations for < or = 10% axillary involvement in group 2 were age and S phase for tubular histology and differentiation for ductal histology. In a multivariate analysis, increasing tumor size was the only statistically significant correlate for axillary involvement (group 2) and for increasing number of positive nodes (group 1).

CONCLUSIONS

A multivariate model of tumor size and age combined with staging techniques can successfully confirm or assess extent of axillary metastases in breast carcinoma.

A predictive index of axillary nodal involvement in operable breast cancer

We investigated the association between pathological characteristics of primary breast cancer and degree of axillary nodal involvement and obtained a predictive index of the latter from the former. In 2076 cases, 17 histological features, including primary tumour and local invasion variables, were recorded. The whole sample was randomly split in a training (75% of cases) and a test sample. Simple and multiple correspondence analysis were used to select the variables to enter in a multinomial logit model to build an index predictive of the degree of nodal involvement. The response variable was axillary nodal status coded in four classes (N0, N1-3, N4-9, N > or = 10). The predictive index was then evaluated by testing goodness-of-fit and classification accuracy. Covariates significantly associated with nodal status were tumour size (P < 0.0001), tumour type (P < 0.0001), type of border (P = 0.048), multicentricity (P = 0.003), invasion of lymphatic and blood vessels (P < 0.0001) and nipple invasion (P = 0.006). Goodness-of-fit was validated by high concordance between observed and expected number of cases in each decile of predicted probability in both training and test samples. Classification accuracy analysis showed that true node-positive cases were well recognised (84.5%), but there was no clear distinction among the classes of node-positive cases. However, 10 year survival analysis showed a superimposible prognostic behaviour between predicted and observed nodal classes. Moreover, misclassified node-negative patients (i.e. those who are predicted positive) showed an outcome closer to patients with 1-3 metastatic nodes than to node-negative ones. In conclusion, the index cannot completely substitute for axillary node information, but it is a predictor of prognosis as accurate as nodal involvement and identifies a subgroup of node-negative patients with unfavourable prognosis.

Prognosis of patients with breast cancers up to 1 cm in diameter

The prognosis of patients with tumours measuring up to 1 cm diameter was examined. 336 patients treated at Guy's Hospital between 1975 and 1994 were reviewed. Of these, 103 (31%) were lymph node-positive, with approximately one third of these having one node involved, one third two to three nodes and one third four nodes or more. A similar proportion of those with palpable and impalpable tumours had axillary node involvement. Patients with axillary node involvement had a significantly worse prognosis and those node-positive patients with impalpable cancers had a significantly worse outcome compared with node-positive palpable cases. When patients were subdivided on a basis of nodal status and age (< or = 50 or > 50), node-positive women aged > 50 fared significantly better than younger women. These data suggest the need to know accurately the axillary nodal status of patients with small breast cancers, whether symptomatic or detected by screening. This knowledge will allow women with curable cancers to be identified together with those who have a worse prognosis and who will be likely to benefit from systemic adjuvant therapy.

Axillary lymph nodes and breast cancer: a review

BACKGROUND

The value of surgical staging and treatment of the axillary lymph nodes with either surgery or radiotherapy in the initial management of patients with Stage I or II invasive breast cancer is controversial.

METHODS

A review of retrospective and prospective clinical studies was performed to assess the risks of axillary lymph node involvement and the effectiveness and morbidity of various treatment options.

RESULTS

The risk of axillary lymph node involvement is substantial for most patients, even those with small tumors. The morbidity resulting from a careful Level I/II axillary dissection or moderate-dose axillary radiotherapy is limited. Such treatment is highly effective in preventing axillary recurrence. The symptoms resulting from axillary failure can be controlled in many, but not all, patients. The available data suggest, but do not prove, that the initial use of effective axillary treatment may result in a small improvement in long term outcome in some patient subgroups.

CONCLUSIONS

Most patients should be treated with either axillary surgery or irradiation. Highly selected subgroups of patients may have such low risks of involvement that specific axillary treatment is of little value. However, such subgroups have not yet been well defined. Treatment approaches that do not involve specific axillary treatment should be considered investigational at present, and the patients should be informed as to their potential risks. Prospective clinical studies of these issues should be pursued.