A comparison of axillary node status between cancers detected at the prevalence and first incidence breast screening rounds

Relationship between the method of detection and prognostic factors for breast cancer in a community with a screening programme

Objectives

To analyse and compare the prognostic factors of breast cancer in the target population of our community-screening programme as a function of the method of detection and to analyse the differences in the prognostic factors as a function of the patient's age and the screening episode.

Setting

A Breast Cancer-Screening Programme (BCSP) in Northeast Spain.

Methods

Observational study of all primary malignant breast lesions diagnosed in a woman between 50 and 69 years of age between 18 October 1995 and 31 December 2002. The 16 centres that women from the target population might have attended were contacted.

Results

A total of 225 (37.2%) of the lesions included were diagnosed through the BCSP, 59 (9.7%) interval cancers were detected, and 321 (53.1%) were detected through other circuits. Node involvement was significantly lower in the lesions detected at screening (32%) in comparison to the interval cancers (41.8%) and those detected through other circuits (47.5%). A significantly larger percentage of the interval tumours (28.6%) and the lesions diagnosed outside the BCSP (22.1%) scored 5.4 on the Nottingham Prognostic Index (NPI) than those diagnosed within the programme (10.9%). The relation between the NPI and the detection method was only statistically significant in the 65-69-year-old age group. The NPI score of the tumours detected by the BCSP showed a statistically significant association with age.

Conclusion

This analysis has shown notable differences in some prognostic factors for breast cancer according to the method of detection. Association between age and the a priori prognosis of the malignant lesions arises.

Preoperative selection of symptomatic breast cancer patients appropriate for lymphatic mapping and sentinel node biopsy

BACKGROUND

This study examines whether preoperative ultrasound-assessed tumour diameter and diagnostic core biopsy-determined grade can be used to select those most likely to benefit from SLNB (i.e. those that are "node negative") before their definitive operation.

METHODS

Breast ultrasound (US) and a simultaneous core biopsy was performed in all patients at their initial presentation, and their estimates of tumor size and grade compared with the final pathological specimen (FPS).

RESULTS

Of the T1 group 47% had lymphatic metastases as did 49% of those with grade I or II cancers. By combining these measures, however, subgroups of patients with lower rates of nodal metastases were identified (32% of patients with T1, non-grade III disease had lymphatic disease while only 15% of those with T < 1.5 cm, non-grade III cancers had such metastases).

CONCLUSION

Combination of the US and ultrasound guided core biopsy (UGCB) may however identify subgroups unlikely to have axillary disease that are therefore suitable for SLNB.

Aberrant hypermethylation of ID4 gene promoter region increases risk of lymph node metastasis in T1 breast cancer

ID4 gene is a member of the inhibitor of DNA-binding (ID) family, which inhibits DNA binding of basic helix-loop-helix transcription factors. Certain human primary breast cancers reportedly have low or no expression of ID4 protein, but its role in carcinogenesis and cancer progression is unknown. To determine its possible role, we examined epigenetic inactivation of ID4 gene by promoter hypermethylation in human breast cell lines and T1 breast cancer tissues. Methylation status of ID4 promoter CpG island was assessed by methylation-specific PCR (MSP); ID4 mRNA level was assessed by quantitative real-time RT-PCR. Of eight cell lines, two were fully methylated, four were partially methylated, and two were not methylated. ID4 mRNA level was suppressed in fully methylated cell lines. ID4 hypermethylation was observed in 16 of 24 (67%) node-positive and seven of 36 (19%) node-negative T1 primary breast cancers matched by patient age and tumor diameter. It was a significant risk factor for nodal metastasis (OR 13.1, P=0.0004). ID4 mRNA level was suppressed in hypermethylated cancer specimens (P=0.014). ID4 may play an important suppressive role in tumor progression, and its silencing by hypermethylation may increase the risk of regional lymph node metastasis.

The quotient of number of nodes and tumour size (N/T) from primary breast cancer predicts the clinical course after diagnosis of distant relapse

INTRODUCTION

Breast cancer is a disease with a very variable progression. Primary tumour size and metastatic lymph node involvement are the best indicators of the likelihood of relapse. However, their value in predicting progression following relapse is not clear.

AIM

The aim of this study was to asses whether the relationship between tumour size and the number of lymph nodes involved had any value as predictive factors of post-relapse progression.

METHOD

We established an index defined as the quotient between the number of diseased lymph nodes and the tumour size (in cm).

RESULTS

Applying this index in 230 consecutive patients with metastatic breast cancer, we observed that there was a significant inverse relation between the index and post-relapse progression.

CONCLUSION

We conclude that, at the time of initial diagnosis, the quotient of tumour size and the number of diseased lymph nodes could be a good predictor of time-to-progression following the diagnosis of the metastatic disease.

Does screen-detected breast cancer have better survival than symptomatic breast cancer?

OBJECTIVES

Evidence obtained from several randomized control trials suggest that mortality from breast cancer could be reduced by mammographic screening. However, a recent meta-analysis questioned the general acceptance that screening for breast cancer is beneficial. The purpose of the study was to analyze prospectively collected data from our unit and produce overall and comparative 5-year survival rates for screen-detected and symptomatic breast cancer.

METHODS

Prospectively collected data on all patients diagnosed with invasive breast cancer between January 1993 and December 1994 (24 months), and monitored until the end of 1999, were collated and analyzed. Five-year survival was estimated and broken down by age at diagnosis, tumour size, grade and nodal status. The overall 5-year survival for women with screen-detected cancers was compared with that for women with symptomatically presenting cancers.

RESULTS

Between January 1993 and December 1994, 308 patients with invasive breast cancer were referred to the unit (162 via the breast screening programme and 146 presenting symptomatically). The overall 5-year survival was 85.5% (confidence interval [CI], 80.8-89.1). Small tumour size, low grade and negative nodal status were associated with higher survival rates. Five-year survival of the screen-detected cancer patients (91.7%; CI, 85.8-95.2) was higher than that of patients presenting symptomatically (78.6%; CI, 70.6-84.6; p < 0.001).

CONCLUSIONS

These findings suggest that patients with screen-detected breast cancer may have better survival compared to those with symptomatically detected breast cancer. The results support the argument in favour of a beneficial impact of breast screening programmes on patients' survival.

Breast cancers found by screening: earlier detection, lower malignant potential or both?

A population-based study was performed to compare the characteristics of clinically detected breast cancers and cancers detected by the Dutch screening program. To determine whether differences are most likely to be explained by earlier diagnosis or by the detection of biologically different cancers in the screening program, comparisons were stratified according to tumor size. Data were obtained from the population-based Eindhoven Cancer Registry. During the period 1996-1999, 568 screen-detected and 630 clinically detected invasive breast cancers were available for analysis. Compared with patients with clinically detected breast cancer, women with screen-detected breast cancer had smaller tumors (P < 0.0001), were more likely to have negative lymph nodes (P < 0.0001), tumors with a positive estrogen (P = 0.007) or progesterone (P = 0.019) receptor status and a lower mitotic activity index (P = 0.009). In the group with cancers < or = 1.0 cm the screen-detected were more likely to have negative estrogen receptors (P = 0.027). The group with screen-detected tumors 1.1-2.0 cm across were more likely to have positive estrogen and progesterone receptors (P = 0.005 and P = 0.044, respectively) and tended to have a lower mitotic activity index (P = 0.078). No significant differences were found between screen-detected and clinically detected breast cancers of 2.1-3.0 cm across. After adjustments for tumor size, most of the differences between clinically detected and screen-detected breast cancers disappeared, suggesting that screen-detected breast cancers represent tumors in an earlier phase of their development, not a biologically different class.

Sentinel node biopsy: an in depth appraisal

Sentinel node biopsy (SNB) in primary breast cancer has been taken-up widely to avoid the morbidity attributable to axillary node clearance (ANC). Currently many issues surrounding SNB are undecided. This review summarises why some form of axillary surgery is required and presents data on all aspects of SNB including methodology, clinical results and problems that may delay the introduction of SNB as best practice for all patients with primary breast cancer. There is no long or medium term data relating to the consequences of replacing ANC with SNB, but the mechanisms and probable magnitude of both beneficial and detrimental effects are estimated. A low level of false negative results are inherent to the technique but it is demonstrated that SNB is likely to have an only marginal (0.6%) effect on survival that would be undetectable by clinical trials. Patient sub-groups particularly likely to benefit from SNB are identified.

Factors correlating with lymph node metastases in patients with T1 breast cancer

BACKGROUND

Identification of reliable predictors of axillary metastases (ALNM) may be useful in selecting appropriate management for patients with T1-size breast cancer. This study was undertaken to determine the degree of correlation between ALNM and several variables, including age, race, menopausal status, palpability, tumor size, positive margin on initial excision, histology, grade, lymphatic invasion (LI), estrogen receptor status (ER), progesterone receptor status, S-phase, and ploidy.

METHODS

Data from 1416 patients with T1 breast cancers treated at Columbia-Presbyterian Medical Center between 1989 and 1998 was reviewed. Patients with multifocal tumors were excluded.

RESULTS

Mean patient age was 57.5 years (SD = 12.0); 65% of the patients were postmenopausal. One hundred thirty-one patients with Tla (< or =0.5 cm), 435 with T1b (0.6-1.0 cm), and 850 patients with T1c (1.1-2.0 cm) lesions were studied. The overall rate of ALNM was 23%. AM was identified in 11% of T1a, 15% of T1b, and 29% of T1c patients. Statistically significant factors from univariate analysis were age, palpability, skin changes, tumor size, LI, histology, grade, ER status, and positive margin on initial excision.

CONCLUSIONS

Axillary staging by either sentinel lymph node biopsy or level I/II axillary dissection is indicated for most T1 breast cancer patients. Omission of axillary staging can be considered for highly selected patients with T1a cancers.

Impact of axillary dissection on staging and regional control in breast tumors < or = 10 mm--the DBCG experience. The Danish Breast Cancer Cooperative Group (DBCG), Rigshisoutalet, Copenhagen, Denmark

Data from 4771 patients with tumor diameters < or = 10 mm were analyzed. Results of surgery and pathoanatomical examinations indicated that nodal status was related to diameter, but not to number of nodes removed. More axillary metastases were found in group T1b tumors than in T1a. In 8% of tumors, at least 4 positive nodes were identified. Mean number of positive nodes was related to number of nodes removed, and when 10 or more nodes were removed a significantly lower axillary recurrence rate and better recurrence-free survival were demonstrated, confirming that axillary surgery has two goals: staging and regional disease control. Age, receptor status, grade and histological type, but not tumor location, were related to prognosis. In accordance with the classical prognostic factors, it was not possible to define a patient group where axillary surgery was superfluous. We conclude that proper staging and regional control renders a full axillary level I-II dissection necessary.

Management of the axilla in early breast cancer: is it time to change tack?

The standard surgical treatment of the axilla in patients with early breast cancer is about to undergo a radical change. Although axillary dissection is an excellent procedure for both staging and local control, particularly in the clinically positive axilla, it has considerable morbidity and may understage a significant proportion of patients, because it will usually miss micrometastases that can occur in approximately 10% of 'node negative' patients. An increasing number of patients whose tumours are either non-invasive (ductal carcinoma in situ; DCIS), micro-invasive, tubular cancers or low-grade T1a tumours without lymphovascular invasion may be spared axillary surgery because the risk of axillary disease is 0-3%. Many studies, both prospective trials and large retrospective series, show that axillary radiotherapy alone provides similar local control rates to axillary dissection in patients with clinically negative axillas. Primary treatment of the axilla with radiotherapy alone, however, does not allow appropriate staging. Sentinel lymph node biopsy is being increasingly used in patients with breast cancer to provide this information. When a sentinel node is identified it is equal to or better than axillary dissection for staging the axilla and, if the node is positive, it will help select patients who should then proceed to further axillary surgery or axillary radiotherapy. Although sentinel lymph node biopsy is being rapidly adopted in many centres worldwide, the results of randomized controlled trials are needed before it can be recommended as the standard of care.

Significance of axillary lymph node metastasis in primary breast cancer

PURPOSE

Axillary lymph node status is the single most important prognostic variable in the management of patients with primary breast cancer. Yet, it is not known whether metastasis to the axillary nodes is simply a time-dependent variable or also a marker for a more aggressive tumor phenotype. The purpose of this study was to determine whether nodal status at initial diagnosis predicts outcome after relapse and therefore also serves as a marker of breast cancer phenotype.

PATIENTS AND METHODS

Survival experience after first relapse in 1,696 primary breast cancer cases was analyzed using Cox proportional hazards regression. The following explanatory variables and their first-order interactions were considered: number of axillary lymph nodes involved (zero v one to three v four or more), hormone receptor status (any estrogen receptor [ER] negativity v ER negativity/progesterone receptor positivity v other ER positivity), primary tumor size (< 2 cm v 2 to 5 cm v > 5 cm), site of relapse (locoregional v distant), disease-free interval (< 1.5 years v 1.5 to 3 years v > 3 years), adjuvant endocrine therapy (none v any), adjuvant chemotherapy (none v any), and menopausal status (pre-, peri-, or postmenopausal).

RESULTS

Axillary lymph node status, site of relapse, and hormone receptor status were all highly significant as main effects in the model. After adjustment for other variables, disease-free interval alone was only modestly significant but interacted with nodal status. After disease-free interval, hormone receptor status, and site of relapse were accounted for, survival after relapse was poorer in node-positive cases, when compared with node-negative cases. The hazard ratios for patients with one to three and four or more involved nodes were 1.2 (95% confidence interval [CI], 0.8 to 1.9) and 2.5 (95% CI, 1.8 to 3.4), respectively.

CONCLUSION

Patients with four or more involved nodes at initial diagnosis have a significantly worse outcome after relapse than node-negative cases, regardless of the duration of the disease-free interval. We conclude that nodal metastasis is not only a marker of diagnosis at a later point in the natural history of breast cancer but also a marker of an aggressive phenotype.

Screen detected breast cancer in an Asian population: pathological findings of the Singapore breast screening project

We document the pathological characteristics of 135 cancers detected in 132 predominantly Chinese women in the Singapore breast screening project. Thirty-four (25%) screen detected tumours were in situ ductal cancers; 98 (73%) invasive, while three (2%) women with malignant fine needle aspirate smears refused further treatment. The median size of in situ cancers was 10 mm; the majority (56%) demonstrated a comedo pattern. Of the invasive tumours which had a median size of 15 mm, three (3%) were microinvasive, 75 (77%) infiltrative ductal, three (3%) invasive lobular, and the remaining 17 (17%) special types or others. Histologic grading revealed 23 (24%) grade I, 52 (53%) grade II, 19 (19%) grade III and four (4%) ungraded cases. Sixty-three (65%) of the invasive cancers were node negative, while 64% of all screen detected malignancies were Stages 0 (in situ) or I. From the pathological perspective, problems of borderline lesions, microinvasion, grade assessment and histological subtyping have to be addressed.

Routinely available indicators of prognosis in breast cancer

Diagnosis coupled with prognostication is the challenge for and charge of the pathologist. In this time of rapidly developing basic knowledge and increasing sophistication in the evaluation of prognostic information, there has also been an important re-evaluation of the validity, reliability, and relevance of classic histopathology. Also, the precision of and criteria for evaluating tumor size and status of regional lymph nodes is under study. Our emphasis in this review is tissue pathology and further, its practical relevance to patient management. Histopathology remains the basis of diagnosis universally; the addition of other elements will increase precision of prediction, particularly of responsiveness to individual therapies. Histologic grade may be integrated to substratify high and low stage cases into prognostically more useful subsets. Histologic types also interact with size and nodal status to predict patients with excellent prognosis. Further refinement of these parameters may occur by analysis within clinical, pathologic, or therapeutic subsets.

Accuracy of AJCC staging for breast cancer patients undergoing re-excision for positive margins. American Joint Committee on Cancer

BACKGROUND

The current AJCC protocol for breast cancer staging does not include additional tumor found at the time of re-excision in the calculation of tumor size. We hypothesize that the AJCC protocol may result in understaging and undertreatment of breast cancer patients who have additional tumor found at re-excision.

METHODS

In a retrospective chart review of breast cancer patients, patients with tumor present at re-excision for positive margins were placed in group 1 (n=72); patients with no tumor present at re-excision, or who underwent a single, negative margin procedure were placed in group 2 (n=147).

RESULTS

Patients in group 1 had a higher risk of nodal metastases when compared to patients in group 2. Mean tumor size did not differ significantly between the subgroups. Positive re-excision was strongly associated with lymph node metastases on multivariate analysis after correction for age, grade, stage, and lymphatic invasion (odds ratio=3.13, 95% CI=1.58 6.18, P=.0011).

CONCLUSIONS

Current AJCC guidelines may result in undertreatment of breast cancer patients with positive re-excisions. The presence of additional tumor at the time of re-excision should be considered when determining the need for systemic therapy, and may be relevant in determining T stage.