[The predicting value of the 8th edition of American Joint Committee on Cancer staging manual in mucinous breast cancer].

Objective: The current study aimed to evaluate the predictive performances of anatomic staging system (AS) and prognostic staging system (PS) proposed in the 8th edition American Joint Committee on Cancer (AJCC) staging manual in patients with pure mucinous breast cancer (PMBC). Methods: Clinicopathologic features and follow-up information were collected from a total of 3628 patients with PMBC. Breast cancer-specific survival (BCSS) were compared among patients in different stage groups. Likelihood ratio (LR) χ(2), Akaike information criterion (AIC) and Harrell's concordance index (C-index) were used to evaluate the predictive performances of AS and PS in PMBC. Results: In PMBC, BCSS was associated with tumor size (P=0.002), lymph node status (P=0.002), grade(P=0.003), PR status(P=0.017)and the receipt of radiation. Compared to AS, 1326 patients (37.54%) underwent stage change after applying PS, with 6.50% upstaged and 37.04% downstaged. There were significant differences in BCSS among patients of different stages under the AS and PS (P<0.001). However, PS was not superior to AS in predicting prognosis (AS vs PS, LR χ(2): 16.41 vs 17.5; AIC: 357.44 vs 358.35; C-index, 0.72 vs 0.73, P=0.667). Conclusions: Both of AS and PS proposed in the 8th edition American Joint Committee on Cancer (AJCC) staging manual were predictive factors in patients with PMBC. Compared with AS, the PS did not show superiority in prognosis prediction among patients with PMBC.

[Strategies of surgical and comprehensive management of breast cancer patients with local regional recurrence].

Breast conserving surgery and sentinel lymph node biopsy are widely used in early breast cancer treatment. Right now, the mode of local regional recurrence (LRR) has significantly changed and the rate of ipsilateral breast tumor recurrence and axillary lymph node recurrence are steadily increasing. Due to its relatively low incidence of LRR compared with distant metastasis, inconsistent of pre-recurrence treatment, difficulty in surgical treatment, and few prospective clinical studies, there are rising new challenges for clinical management of LRR patients. In this article, based on new theory of LRR, clinical diagnosis and treatment progress, and our own clinical practice experience for LRR breast cancer patients, we propose that we should make pathological diagnosis and do systemic evaluation for LRR disease, then considering it as a curable disease, and integrating local and systemic comprehensive treatment for LRR patients, thus to improve their disease outcome.

[Factor analysis of diagnosis and surgical treatment of local regional recurrence in breast cancer patients].

Objective: To analyze the association between clinicopathological factors and clinical diagnosis, treatment and surgery of local regional recurrence (LRR) in breast cancer. Methods: A retrospective study was done to evaluate consecutive 7 823 breast cancer LRR cases between January 2009 and August 2018 at Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine. A total of 108 LRR patients were enrolled: 35 cases (32.4%) with ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery, 40 cases (37.0%) of chest wall recurrence (CR), and 33 cases (30.6%) with regional lymph node recurrence (LNR). All patients were female, aged from 26 to 83 years with a mean of 49 years. Clinicopathological factor and its relationship with different sites of LRR and following surgical choice were analyzed by χ(2) test, rank-sum test and Logistic regression. Survival analysis were performed between different LRR patterns and whether undergoing second surgery. Kaplan-Meier survival curves and Log-rank tests demonstrated the distribution of overall survival. Results: Both univariate analysis and multivariate analysis found that axillary lymph nodes (ALN) status (OR=7.27, 95% CI: 1.30 to 40.53, P=0.042) and disease-free interval (OR=0.18, 95% CI: 0.06 to 0.60, P=0.013) were related to different site of LRR. Compared with patients with IBTR, LNR and CR patients had a higher rate of ALN metastasis and a shorter disease-free interval. A total of 36 LRR patients underwent following surgery. In univariate analysis, initial ALN surgery (χ(2)=16.705, P=0.001), pathological type (χ(2)=7.047, P=0.03), ALN status (χ(2)=10.812, P=0.002), disease-free interval (χ(2)=6.118, P=0.023) and LRR site(χ(2)=19.328, P=0.000) were associated with surgical treatment for LRR patients. Multivariate analysis demonstrated that only site of LRR was independently associated with surgery (OR=0.17, 95% CI: 0.05 to 0.65, P=0.024). The 5-year overall survival was 100% and 60.1% (P=0.018) for LRR patients treated with surgery or not. Furthermore, CR patients had significantly worse overall survival than LNR and IBTR patients, with 5-year overall survival 53.1%, 73.5%, and 100% respectively (P=0.021). Conclusions: Initial lymph nodes metastasis and disease-free interval are associated with different site of LRR. LRR site significantly influenced following surgery choice after LRR, which are both related with overall survival after LRR.

[Analysis of the factors influencing adjuvant chemotherapy decisions for triple negative breast cancer].

Objective: To analyze adjuvant chemotherapy decisions for triple negative breast cancer (TNBC), and explore the influencing factors in the multidisciplinary treatment (MDT) modality. Methods: A retrospective analysis was performed. The cases with invasive TNBC who underwent surgery and MDT discussion for adjuvant treatment in Ruijin Hospital, from April 2013 to June 2015, were recruited. The patients' clinicopathological characteristics were analyzed and adjuvant treatment suggestions from MDT were obtained. Here the chemotherapy decision alteration was defined as a disagreement in chemotherapy or not, or inconsistence in regimens between the attending doctor and the multidisciplinary team. Results: A total of 194 patients aged ≤70 years old were enrolled in the multidisciplinary discussion, and 187 patients (96.4%) were suggested to receive chemotherapy. When compared the opinions of the attending doctor to suggestions of the multidisciplinary team, we found that the percentage of chemotherapy decision alteration reached 22.7% (39/172), of which 94.9% (37/39) were inconsistence in chemotherapy regimens. There were 119 patients who were recommended to receive epirubicin plus cyclophosphamide (EC) followed by docetaxel (T) or weekly paclitaxel (wP) regimens. Before the announcement of results for the E1199 trial, EC-T accounted for 62.5% (55/88), and EC-wP accounted for 37.5% (33/88) for this group of patients. After that, the proportion of EC-T was decreased to 22.6% (7/31) and proportion of EC-wP increased to 77.4%(24/31) (P<0.001). In addition, a total of 20 patients were suggested to receive platinum based chemotherapy. The proportions were 9.3% in cases with invasive ductal carcinoma, and 33.3% in cases with metaplastic carcinoma, respectively (P=0.016). Conclusions: The adjuvant chemotherapy decision for TNBC patients is altered in 22.7% of the patients after MDT discussion. After the announcement of SABCS E1199 results, more patients are suggested to receive EC followed by weekly paclitaxel. There is a lack of detailed evidence for platinum based adjuvant chemotherapy for TNBC, and more patients with metaplastic carcinoma receive platinum based adjuvant chemotherapy.

[Clinical utility study of 21-gene assay in 927 Chinese patients with early breast cancer].

Objective: To investigate the distribution patterns of 21-gene assay and its influencing factors in Chinese patients with early breast cancer. Methods: Nine hundred and twenty-seven early breast cancer patients were retrospectively recruited from January 2009 to December 2015 at Ruijin Hospital, Shanghai Jiaotong University School of Medicine. The 21-gene reverse transcriptase-polymerase chain reaction(RT-PCR) assay were conducted in paraffin-embedded tumor tissues to calculate the Recurrence Score(RS). Immunohistochemistry(IHC) assay was used to measure the expression levels of estrogen receptor(ER), progesterone receptor(PR) and Ki-67. Concordances of RT-PCR and IHC results were assessed. Correlations of RS and classical clinicopathological factors were evaluated, and logistic regression were applied to determine independent predictive factors for RS. Results: The median RS of 927 patients was 23(range: 0~90), and the proportions of patients categorized as having a low, intermediate, or high risk were 26.5%, 47.7% and 25.8%, respectively. The distribution of RS varied significantly according to different tumor grade, T stage, PR status, Ki-67 index and molecular subtypes(P<0.05 for all). Grade, PR status and Ki-67 index were independent predictive factors for RS. ER, PR status and Ki-67 index showed significantly correlation between RT-PCR and IHC assays, and the concordance rates for ER and PR status were 98.7% and 87.8%, respectively. Conclusions: RS significantly correlated with tumor grade, T stage, PR status, Ki-67 index and subtypes. Grade, PR status and Ki-67 index can independently predict RS. Remarkable concordances of ER, PR status and Ki-67 index are found between RT-PCR and IHC assays.

[Effect of 21-gene recurrence score on chemotherapy decisions for patients with estrogen receptor-positive, epidermal growth factor receptor 2-negative and lymph node-negative early stage-breast cancer].

Objective: To investigate the effect of 21-gene recurrence score on adjuvant chemotherapy decisions for patients with estrogen receptor (ER)-positive, epidermal growth factor receptor 2 (HER-2)-negative and lymph node (LN)-negative early stage-breast cancer. Methods: One hundred and forty-eight patients with ER+ , HER-2- and LN- early stage breast cancer were recruited in the Ruijin hospital, Shanghai Jiao Tong University School of Medicine. The 21-gene recurrence score (RS)assay was performed and systemic therapeutic decisions were made before and after knowing the RS results under multidisciplinary discussion. The effects of RS assay and the other influential factors on adjuvant chemotherapy decision were further analyzed. Results: After knowing the RS results, treatment decisions were changed in 26 out of 148 patients(17.6%). Among them, 9 out of 26 patients were not recommended for chemotherapy; 16 of 26 had treatment recommendation changed to chemotherapy, and chemotherapy regimen was changed in the last one patient. Multivariate analysis showed that RS, age and histological grade were independent factors of decision-making for adjuvant chemotherapy. Conclusion: Our results suggest that 21-gene recurrence score significantly influences decision making for adjuvant chemotherapy in patients with ER+ , HER-2- and LN- early stage breast cancer.

[Multi-gene assay profiling testing and individualized therapy in breast cancer].

Breast cancer is a heterogenetic disease. Multi-gene assay profiling can classify breast cancer into several molecular subtypes, which is better to predict disease prognosis and treatment response. Two prospective clinical trials validated the prognosis predictive value of 21 gene recurrence score and MammaPrint in early breast cancer, than to decrease the prescription of adjuvant chemotherapy and avoid side effect of chemotherapy. New multi-gene assay profiling integrating clinic-pathological factors or reflecting disease development and metastasis can help us predict disease outcome better, thus to achieve individualized therapy in breast cancer.

[Surgical treatment and prognosis of ductal carcinoma in situ: 526 cases analysis].

Objective: To evaluate the choice of surgical treatment of ductal carcinoma in situ (DCIS) and its impact on long-term outcomes. Methods: A retrospective analysis of the clinicopathological features and treatment protocol of DCIS patients who underwent surgical treatment in Comprehensive Breast Health Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine from January 2009 to August 2016 was done. The factors which could affect surgical treatment were analyzed by χ(2) test and Logistic regression. Survival analysis were performed between different surgical approaches. Kaplan-Meier survival curves and Log-rank tests demonstrated the distribution of disease free survival and overall survival. Results: A total of 526 patients were enrolled in this study, 405 cases (77.0%) underwent mastectomy, 121 cases (23.0%) underwent breast-conserving surgery, of which 88 cases received radiotherapy after breast-conserving surgery. It was shown by univariate and multivariate analysis that age>50 years (OR=0.631, 95% CI: 0.413 to 0.965, P=0.034), first symptom of nipple discharge (OR=0.316, 95% CI: 0.120 to 0.834, P=0.020), excision biopsy (OR=1.831, 95% CI: 1.182 to 2.835, P=0.007) and tumor size >3 cm (OR=0.422, 95% CI: 0.206 to 0.864, P=0.018) were significantly correlated with choice of surgical treatment for breast lesions. Axillary lymph node dissection was performed for 118 cases (22.4%), with sentinel lymph node biopsy for 327 cases (62.2%), and none for 81 cases (15.4%). There was significant statistical difference in the choice of axillary lymph node management in patients of different age (χ(2)=8.124, P=0.017), biopsy type (χ(2)=35.567, P=0.000), breast operation type (χ(2)=149.118, P=0.000) and tumor size (χ(2)=13.394, P=0.010). The 5-year disease free survival rates was 95.7%, 89.6% and 100%, respectively, for mastectomy group, breast-conserving surgery group and breast-conserving surgery plus radiotherapy group. And the 5-year overall survival rates for three groups were 99.0%, 100% and 100%. The differences were not statistically significant (P=0.427, 0.777). Conclusions: For DCIS patients, age, first symptom and tumor size are independent predictors of breast surgery. The choice of axillary lymph node surgery is influenced by age, biopsy, operation type, and tumor size. Different surgical treatment options has no significant effect on disease-free survival and overall survival in DCIS patients.

[Factors related to adjuvant ovarian function suppression in premenopausal breast cancer patients].

OBJECTIVE: To analyze the applied condition of ovary function suppression (OFS) before and after joint analysis of TEXT and SOFT trials and SOFT trial, and to identify the relevant factors of OFS usage. METHODS: The analysis was performed in premenopausal women with hormone receptor (HR) positive breast cancer receiving surgical treatment from Apr 2013 to Oct 2015 in Ruijin Hospital, Shanghai Jiaotong University School of Medicine. Adjuvant treatment strategy was made in the multidisciplinary team (MDT) meetings. We analyzed the applied condition of OFS before and after joint analysis, SOFT trial and its relevant factors. RESULTS: Among 454 patients, 114 (25.1%) patients received OFS. Before the results of joint analysis came out, all the patients (38/38) received OFS together with tamoxifen (TAM); after the results came out, clinicians began to put OFS with exemestane into practice, among 76 patients, 41(53.9%) patients received OFS with exemestane while 35 (46.1%) patients received OFS together with TAM. Before the results of SOFT trial came out, 71 out of 310 (22.9%) patients received OFS while 43 out of 144 (29.9%) patients received OFS after that. No significant difference was found between the proportion of patients receiving OFS before and after the results of SOFT trial came out (P=0.112). Age, histological grade, pN status, Ki-67 status, molecular subtype and acceptance of chemotherapy were correlated with OFS treatment (P<0.05). Age, tumor grade and pN were independent significant predictors of OFS usage. CONCLUSIONS: After the results of joint analysis came out, clinicians began to apply OFS with exemestane to premenopausal women with HR positive breast cancer. There is no significant difference between the proportion of patients receiving OFS before and after SOFT trial. Age, tumor grade and pN status are independent significant predictors of OFS treatment. Patients younger than 40, with histological grade Ⅱ or Ⅲ tumor and with pN1 or pN2 status are prone to receive OFS.

Weekly paclitaxel plus carboplatin is an effective nonanthracycline-containing regimen as neoadjuvant chemotherapy for breast cancer.

BACKGROUND: To evaluate the activity and safety of nonanthracycline-containing weekly PCb [paclitaxel (Taxol) plus carboplatin] regimen in neoadjuvant treatment of breast cancer. PATIENTS AND METHODS: Eligible patients were assigned to receive four cycles of PCb with dose of paclitaxel 80 mg/m(2) and carboplatin at an area under the curve of 2 mg x min/ml, given day 1, day 8 and day 15 of every 4 weeks. Pathological complete remission (pCR) was defined as no invasive cancer in breast and axillary samples. RESULTS: Overall, 107 consecutive patients received weekly PCb treatment from December 2007 to December 2008, and one was diagnosed with bilateral breast cancer. A total of 85.2% of patients were initially diagnosed with stage III diseases. Clinical response rate was 86.1% with complete remission rate 32.4%. Twenty-one patients achieved pCR after neoadjuvant treatment, with pCR rate 19.4%. The incidence of grade 3-4 neutropenia was 40.2% and only one patient was reported with febrile neutropenia. Severe anemia and thrombocytopenia occurred in 4.7% and 0.9%, respectively, of patients. Peripheral neuropathy was frequent but never severe. Patients with estrogen receptor-negative, progesterone receptor-negative, triple-negative or human epidermal growth factor receptor 2 (Her2)-positive subtype disease had higher pCR. CONCLUSIONS: Weekly PCb regimen was very active and tolerable as neoadjuvant treatment of breast cancer. This weekly PCb regimen should consider as a reasonable nonanthracycline-containing option in the neoadjuvant treatment of breast cancer.

Outcome of postmastectomy radiotherapy after primary systemic treatment in patients with clinical T1-2N1 breast cancer.

PURPOSE: The role of postmastectomy radiotherapy following primary systemic treatment in patients with clinical T1-2N1 breast cancer remains a controversial issue. The purpose of this study was to evaluate the benefit of postmastectomy radiotherapy following primary systemic treatment. PATIENTS AND METHODS: Between 2005 and 2012, in two independent institutions, female patients with T1-2N1 breast cancer receiving primary systemic treatment followed by mastectomy and lymph node dissection because bad response, then treated with or without chest wall and regional lymph node irradiation have been studied retrospectively. The patients received normofractionated radiotherapy using 3D conformal photons or electron techniques. Locoregional recurrence-free survival, distant metastasis-free survival and disease-free survival were calculated using Kaplan-Meier method. Univariate analysis of potential prognostic factors was performed using log-rank test. RESULTS: Eighty-eight patients have been studied. Of them, 75 patients received postmastectomy radiotherapy. At surgery, 53 patients achieved ypN0. Median follow-up was 67 months. Postmastectomy radiotherapy significantly improved locoregional recurrence-free survival, with a 5-year rate of 96.9% versus 78.6% in the group that did not have postmastectomy radiotherapy. In the subgroup of 53 patients achieving ypN0, postmastectomy radiotherapy improved locoregional recurrence-free survival (a 5-year rate of 94.7% vs. 72.9%), distant metastasis-free survival (a 5-year rate of 92.8% vs. 75%) and disease-free survival (a 5-year rate of 92.9% vs. 62.5%). By univariate analysis, postmastectomy radiotherapy was the only significant prognostic factor affecting locoregional recurrence-free survival. CONCLUSIONS: For patients with clinical T1-2N1 disease, postmastectomy radiotherapy could significantly improve locoregional recurrence-free survival after primary systemic treatment and be even more therapeutic in the subgroup of patients with good response for primary systemic treatment by improving locoregional recurrence-free, distant metastasis-free and disease-free survival. Larger prospective studies are needed to confirm our findings.

Antigenic profiles of disseminated breast tumour cells and microenvironment in bone marrow.

AIMS: Thirty per cent of breast cancer patients with axillary lymph node negative at primary surgery will relapse within 10 years. This may be caused by disseminated tumour cells from the primary tumour. This study report the phenotypic profiles of disseminated tumour cells and microenvironmental characteristics in bone marrow of breast cancer. METHODS: We detected the biologic markers on the disseminated tumour cells with immunocytochemical staining, analysed the immunological changes through flow-cytometry, and investigated the u- PA activity in the plasma of bone marrow. RESULTS: With the immunocytochemical staining of EMA and CK19, we detected micrometastasis in thirty out of 72 (41.67%) breast cancer patients. Compared with the primary tumours, disseminated tumour cells expressed low protein cyclin D1, P53, Ki-67, EGFR, and high protein P21. The percentage of memory CD4+ T cells was significantly higher in the micrometastasis-positive group than in the micrometastasis-negative group. Tumour size and axillary lymph node status were found to be significantly correlated with the u- PA activity level. CONCLUSIONS: Immunophenotypic profiles of disseminated tumour cells could be measured by immunocytochemical staining and microenvironment can be analysed by flow cytometry.

Fiberoptic ductoscopy for breast cancer patients with nipple discharge.

BACKGROUND: Breast cancer and precancer are thought to originate in the lining of the milk duct, but until recently, we have not had direct access to this area other than in tissue removed blindly by core biopsy or fine-needle aspiration. Fiberoptic ductoscopy (FDS) is an emerging technique that allows direct visual access of the ductal system of the breast through nipple orifice cannulation and exploration. To date, this technique has been used only in pilot studies. Previously, we have demonstrated that fiberoptic ductoscopy in patients with and without nipple discharge is a safe and effective means of visualizing the intraductal lesion. When combined with cytology, it is a screening technique that has high predictive value. METHODS: We applied ductoscopy to 415 women with nipple discharge with the specific intent of detecting those patients with nipple discharge who had intraductal carcinoma (DCIS) as the basis of their discharge. RESULTS: In this cohort of patients, ductoscopy was successful in visualizing an intraductal lesion in 166 patients (40%). In these cases, ductal lavage following ductoscopy increased the yield of cytologically interpretable ductal epithelial cells 100-fold compared to discharge fluid alone. In the majority of these patients, FDS examination detected lesions that had the appearance of typical papillomas. However, in 10 patients, the intraductal lesion exhibited one of several atypical features, including bleeding, circumferential obstruction, and gross fungating projections. In eight of these patients, the subsequent histopathology turned out to be DCIS. In two of these eight patients, endoscopic biopsy revealed cytologically malignant cells; in two others, ductal lavage (washings) revealed cytologically malignant cells. In three additional patients, although FDS examination uncovered a typical papilloma that was not biopsied, ductal lavage (washings) revealed cytologically malignant cells. On surgical pathology review of the extirpated lesions, all 11 patients were subsequently shown to have DCIS. Of these 11 cases of DCIS that were initially detected with a combination of FDS and ductal lavage cytology, six were completely negative on mammogram and physical exam. CONCLUSION: Although nipple discharge is an unusual presentation for DCIS, in patients with nipple discharge, FDS with ductal lavage cytology is a useful technique for diagnosing DCIS prior to definitive surgery.

Pregnancy-associated breast cancer: a case control and long-term follow-up study in China.

Pregnancy associated (PA) breast cancer is defined when diagnosed during pregnancy or within one year afterwards. To analyze the prognostic factors related to this disease and assess the impact of pregnancy on breast cancer patients, 88 PA breast cancer patients initially treated in the Shanghai Cancer Hospital from 1957 to 1990 were reviewed. A non-PA group including 176 patients individually well matched to the PA group was also analyzed. Univariate analysis suggested prognostic value for clinical tumor size, TNM stage, and breast feeding time among the classic prognostic factors, pregnancy associated factors and treatment modalities were evaluated. Multivariate analysis demonstrated clinical tumor size, TNM stage and axillary lymph node metastasis as independent prognostic factors. Compared with the non-PA group, the PA group was significantly correlated with delay at diagnosis, large size of the tumor, late TNM stage, extension to the skin or chest wall and administration with oophorectomy. The overall survival rates of 5-year, 10-year and 20-year were 40.39%, 36.29% and 30.70%, respectively, which were worse than those in the non-PA group, but did not reach a significant difference (p=0.0536). We are conducting further basic research to analyze the biologic characteristics of PA breast cancer.

Fiberoptic ductoscopy for patients with nipple discharge.

BACKGROUND: Breast carcinoma and precancer are thought to start in the lining of the milk duct or lobule, yet until recently, we have not had direct access to this area other than by blindly removing tissue by core biopsy or fine-needle aspiration. Fiberoptic ductoscopy (FDS) is an emerging technique allowing direct visual access to the ductal system of the breast through nipple orifice exploration. METHODS: We applied ductoscopy to 259 women who had nipple discharge, and we analyzed the visual findings, the cytological washings, and the subsequent histopathology. RESULTS: In 92 (36%) of these women, fiberoptic ductoscopy was successful in detecting an intraductal papillary lesion. Of these observed lesions, 68 (74%) were single papilloma, 21 (23%) were multiple discrete papillomas, and 3 (3%) were diffuse intraductal thickening which corresponded to diffuse papillomatosis on histopathological analysis. The overall positive predictive value of FDS screening was 83%. Of the lesions observed, 29.8% were located in the main (segmental) duct, 43.9% lesions in the first branch, 17.5% lesions in the second branch, 7.9% in the third branch, and 0.9% in the fourth branch. These lesions had an overall average distance of 2.7 cm from the nipple orifice. Ductal washings performed at the time of ductoscopy were effective at obtaining representative exfoliated ductal cells which could be evaluated for the presence of clumps (> 50 cells), clumps with atypia or single ductal cells. The presence of clumps with positive FDS increased the positive predictive value to 86%. CONCLUSIONS: Fiberoptic ductoscopy currently offers a safe alternative to ductography in guiding subsequent breast surgery in the treatment of nipple discharge.

Sentinel lymph node biopsy in breast cancer patients after overnight migration of radiolabelled sulphur colloid.

OBJECTIVE: To evaluate the performance and feasibility of sentinel lymph node biopsy in breast cancer patients using technetium-99m (99mTc) sulphur colloid and gamma probe. METHODS: From May 2000 to March 2001, 70 patients with a tumour less than 5 cm with clinically negative axillary lymph nodes underwent sentinel node biopsy followed by standard axillary dissection. 99mTc sulphur colloid was injected around the primary tumour the day before surgery and a gamma probe was used to detect the sentinel lymph node during the surgical procedure. Sentinel lymph node biopsy was compared with standard axillary dissection for its ability to accurately reflect the final pathological status of the axillary nodes. RESULTS: The sentinel lymph node was successfully identified in 67 of 70 patients (95.71%). The number of sentinel lymph nodes ranged from 1-5 (mean 1.5) and non-sentinel nodes ranged from 5-22 (mean 13.3). Of the 67 patients with successfully identified sentinel lymph nodes, 43.28% (29/67) were histologically positive. Sensitivity of the sentinel lymph node to predict axilla was 82.75%; specificity was 100%. Positive and negative predictive values were 100% and 88.3% respectively. The sentinel lymph node was falsely negative in five patients, yielding an accuracy of 92.53%. Sentinel lymph node biopsy was more accurate for T1 tumours than for T2 tumours. CONCLUSIONS: The gamma probe guided method after overnight migration of 99mTc sulphur colloid is technically feasible for detecting sentinel lymph nodes in most breast cancer patients, accurately predicting the axillary lymph node status, and appears more accurate for T1 lesions than for larger lesions. This minimally invasive axillary staging procedure represents a major advance in the surgical treatment of breast cancer.