Occult axillary lymph node metastases in breast cancer do matter: results of 10-year survival analysis.

Axillary lymph node status is one of the most powerful prognostic factors for patients with breast cancer and is often critical in stratifying patients into adjuvant treatment regimens. In 203 apparently node-negative cases of breast cancer, a combination of immunohistochemical staining and step-sectioning identified occult metastases in 25% of cases. Ten-year follow-up information is available for these patients. Histologic features of the primary tumor and immunohistochemical staining for estrogen receptor, progesterone receptor, Her-2, and p53 were also evaluated. With multivariate analysis, both occult metastases and higher histologic grade of the primary tumor were independent predictors of disease-free survival. Histologic grade was the only significant independent predictor of overall survival. Estrogen receptor, progesterone receptor, Her-2, and p53 status did not predict the presence of metastases or survival when all tumor types were considered together. Metastases >0.5 mm significantly predicted a poorer disease-free survival when invasive ductal carcinomas were considered alone. Histologic grade was significantly associated with disease-free survival in the premenopausal and perimenopausal patients but not in the postmenopausal patients. The presence of occult metastases approached significance for overall survival in the premenopausal and perimenopausal patients but not in the postmenopausal patients.

Occult axillary node metastases in breast cancer: their detection and prognostic significance.

Although the presence of axillary node metastases in breast cancer is a key prognostic indicator and may influence treatment decisions, a significant proportion of patients diagnosed as axillary node negative (ANN) using standard histopathological techniques may have occult nodal metastases (OMs). A combination of limited step-sectioning (4 x 100 microns intervals) and immunohistochemical staining (with cytokeratin (MNF.116) and MUC1 (BC2) antibodies) was used to detect OM in a retrospective series of 208 ANN patients. OMs were found in 53 patients (25%), and both step-sectioning and immunohistochemical detection significantly improved detection (P < 0.05). Detection using BC2 (25%) was superior to MNF.116 (18%) and haematoxylin and eosin (H&E) (8%). OMs were found in 51 patients using only the first and deepest sectioning levels and BC2 staining. OMs were more frequently found in lobular (38%) than ductal carcinoma (25%), and more frequently in women less than 50 years (41%) than in older women (19%). Univariate overall and disease-free survival analyses showed that the presence, size and number of OM had prognostic significance as did tumour size (disease-free only) and histological and nuclear grade (P > 0.05). Cox multivariate proportional hazard regression analyses showed that the presence and increasing size of OMs were significantly associated with poorer disease-free survival, independently of other prognostic factors (P < 0.05). However there was not a significant independent association of the presence of occult metastases with overall survival (P = 0.11). These findings have important implications with regard to selection of ANN patients for adjuvant therapy.

Prostate-specific antigen (PSA) and cancer-associated serum antigen (CASA) in distinguishing benign and malignant prostate disease.

The Prostate-Specific Antigen (PSA) and the Cancer-Associated Serum Antigen (CASA) assay for the MUC1 mucin were compared in the serum of 303 patients with malignant or benign prostatic disease. Using cutpoints of 4, 10, and 20 micrograms/l, PSA was elevated in 93%, 81%, and 64% of patients with prostate cancer (n = 113), with corresponding specificities of 55%, 84%, and 96% in benign prostate disease (prostatic hyperplasia or prostatitis, n = 190). Using the recommended cutpoint of 4 Units/ml, CASA was elevated in 38% of patients with prostate cancer, with a specificity of 91% in benign disease. PSA and CASA showed a poor correlation in prostate cancer (r = 0.367) and benign disease (r = 0.158), and CASA was elevated in some PSA negative samples. Used together, PSA > or = 20 micrograms/l and CASA > or = 4 kU/l gave perfect specificity in benign disease, with a corresponding sensitivity of 29% (positive and negative predictive values of 100% and 70%, respectively). However, this combination gave no improvement over the use of PSA alone, with sensitivity 47% when the cutpoint was raised to give perfect specificity. These data suggest that CASA is of little use as an adjunct to PSA in the differentiation of benign and malignant prostate disease.

Prognostic significance of MUC1 epithelial mucin expression in breast cancer.

The epithelial mucin produced by the MUC1 gene is present in the apical cell membrane of normal breast epithelial cells and is highly expressed in many breast cancers. Several studies have provided conflicting evidence regarding the relationship between MUC1 expression and survival in breast cancer patients. In this study a detailed immunohistological analysis of MUC1 expression was performed using monoclonal antibody BC2 and was related to other tumor characteristics and patient survival. Patients whose tumors showed MUC1 expression in greater than 75% of tumor cells had significantly poorer disease-free and overall survival (P < .05). The proportion of cells showing cytoplasmic MUC1 expression was prognostically significant, but the proportion of cells that lined gland spaces showing apical membrane staining was of no prognostic significance. A high level of MUC1 expression was significantly associated with the presence of axillary node metastases and estrogen receptors but not with other tumor characteristics.

Mucin expression by transitional cell carcinomas of the bladder.

OBJECTIVE: To examine the presence of a membrane-associated and secreted mucin (MUC1) and a secreted gel-forming mucin (MUC2) in normal and malignant urothelium. MATERIALS AND METHODS: Sections were obtained from archival paraffin blocks from 11 patients with nonmalignant urological conditions and 89 patients with transitional cell carcinomas (TCC). Mucin expression was examined by immunohistochemistry using monoclonal antibodies BC2 and 4F1, reactive with epitopes on the protein core of MUC1 and MUC2 respectively. RESULTS: In normal urothelium MUC1 was limited predominantly to the apical membranes of the umbrella cell layer. MUC1 was present in all cases of TCC, and the pattern of expression divided into three categories: luminal membrane staining only, luminal plus cytoplasmic staining of intermediate +/- basal layers, or staining of only isolated cells or cell groups. These staining patterns were significantly associated with both tumour grade and stage (P < 0.001), with cytoplasmic staining more prevalent in higher grade and stage tumours. MUC2 was not detected in normal urothelium, and was present in 40% of cases of TCC, characterized by intense granular cytoplasmic staining. No association between MUC2 expression and either tumour grade or stage was demonstrated. CONCLUSION: MUC1 mucin was expressed by both normal and malignant urothelium, with increased expression characteristic of higher grade and stage tumours. MUC2 expression was found in 40% of tumours but not in normal urothelium. The role of these mucins in the biology of the bladder requires further investigation.

Expression of MUC2 epithelial mucin in breast carcinoma.

AIMS: To examine the expression of the MUC2 epithelial mucin in breast carcinoma; to relate this to patient survival. METHODS: Sections from 210 breast carcinomas were stained with the anti-MUC2 core protein monoclonal antibody, 4F1, using an immunoperoxidase technique. The proportion of tumour cells positively stained and the localisation and intensity of any staining were recorded. Expression of MUC2 was compared with histological type and grade, tumour size, presence of nodal metastases, presence of oestrogen receptors, and menopausal status. The prognostic value of MUC2 expression was examined using Kaplan-Meier survival analysis. RESULTS: MUC2 mucin was detected in 19% of cases of invasive carcinoma, in 11% of cases of carcinoma in situ, where present, but very rarely in adjacent normal breast epithelium. Presence of MUC2 was significantly associated with a shorter disease free interval (p < 0.05), although the observed difference in duration of overall survival was not significant. CONCLUSIONS: The MUC2 detected in breast carcinoma may be underglycosylated or staining may represent detection of the protein core before the completion of glycosylation. The virtual absence of 4F1 reactivity in normal breast epithelium suggests that, unlike the MUC1 mucin, the MUC2 mucin is not highly expressed by these cells. The mechanism by which expression of MUC2 affects the biology of breast tumours is unclear, although expression may be a reflection of general derepression of genes during tumour progression.