The Feasibility of the Immunohistochemistry Classification to Predicting Prognosis in Breast Cancer |
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Author | ZhuZuoJu |
Tutor | LvShen |
School | Dalian Medical University |
Course | Pathology and Pathophysiology |
Keywords | Breast cancer Immunohistochemistry classification Prognosis Targeted therapy |
CLC | R737.9 |
Type | Master's thesis |
Year | 2011 |
Downloads | 9 |
Quotes | 0 |
Objective: Breast cancer has become the most malignant tumor in women .The traditional treatments for it are surgical operation and chemoradiotherapy. In recent years, with the best understanding of the carcinogenesis and the development of molecular biotechnology, endocrine therapy and molecular targeted therapy are used widely because of their high specificity and low side effects. Both of them should be based on understanding of ER, PR and HER-2 gene expressions. Generally, the traditional pathological type and clinical stage cannot be used to guide endocrine therapy and molecular targeted therapy because of their limitations in reflecting the expressions of ER, PR and HER-2 gene. In 2000, some researchers such as Perou divided breast cancer into 5 different subtypes: luminal A, luminal B, HER-2 (+) subtype, basal-like subtype and normal breast-like subtype according to gene microarray analysis. Furthermore, they found that the classification was well associated with the patient prognosis. However, the detection of gene cannot be used widely due to economic and technical issues. Currently, some researchers divided breast cancers into 5 immunohistochemistry subtypes which related to the molecular classification. The classification would be helpful in deciding therapeutic strategies, but few reports have shown whether the classification can be used in implicating patient prognosis of Chinese. In this study, we classificated the breast cancer into 5 different subtypes according to the protein expressions of ER, PR, HER-2, and CK5/6 detected by immunohistochemistry and analyzed correlations of the classification to clinicopathological parameters, recurrence and 5-year-survival of patients, and then investigated the feasibility of implicating prognosis with the classification.Methods: The breast cancer tissues with clear pathological diagnosis of 170 patients including 109 patients with complete following-up were collected in the third peoples hospital of Dalian from 2000 to 2010. The protein expression of ER, PR, HER-2, CK5 / 6 and KI67 of the tissues were detected by immunohistochemistry. According to results of the detection, the tumors were classificated into 5 immunohistochemistry subtypes : luminal A [ER (+) or PR (+) and HER-2 (- )],luminal B [ER (+) or PR (+) and HER-2 (+)], HER(+) subtype [ER (-), PR (-) and HER-2 (+)], basal-like subtype [ER (-), PR (-) and HER-2 (-), CK5 / 6 (+)] and normal breast-like subtype [ER (-), PR (-) and HER-2 (-), CK5 / 6 (-)].Furthermore, we analyzed the relationship of the immunohistochemistry subtypes: the age, TNM, tumor size, node metastasis, histological grade, pathological types, invasion of vessel or nerve, recurrence and 5-year-survival in the patients. And then investigated the possibility of the classification used to indicate the patients prognosis.Results:1. The relationship between the clinicopathological parameters and the protein expressions of ER, PR, HER-2 and CK5/6.1.1 The positive rate of ER protein expression in breast cancer was 60.6%. The clinical stage and histological grade of tumors were significantly lower and the size of tumors was significantly smaller in group with ER protein expression than those without (P <0.05), but the age, node metastasis, invasion of vessel or nerve, recurrence and 5-year-survival was not associated with the expression (P> 0.05).1.2 The positive rate of PR protein expression in breast cancer was 53.5%. The size of tumors was significantly smaller and the recurrence was significantly lower rate in group with PR protein expression than those (P <0.05), but the age, clinical stage, node metastasis, histological grade, pathological type, invasion of vessel or nerve and 5-year-survival was not associated with the expression (P> 0.05).1.3 The positive rate of HER-2 protein expression in breast cancer was 27%. The rate of recurrence in tumors with HER-2 protein expression was significantly higher than that without (P<0.05), but the age, clinical stage, tumor size, lymph node metastasis, histological grade, pathological types, invasion of vessel or nerve and 5-year-survival were not associated with the expression (P>0.05).1.4 The positive rate of CK5/6 protein expression in breast cancer was 41.8%. The clinical stage of tumors was significantly lower and the size of tumors was significantly larger with CK5/6 protein expression in group than those without (P <0.05), but the age, node metastasis, histological grade, pathologic types, vessel or nerve, recurrence and 5-year-survival were not associated with the expression (P> 0.05).2. The relationship between the clinicopathological parameters and the immunohistochemistry classification.Luminal A, luminal B, HER-2 (+) subtype, basal-like subtype and normal breast-like subtype accounted for 58.2 % (99/170), 6.5% (11/170), 6.5% (11/170), 12.3% (21/170) and 16.5% (28/170) of all cases respectively. The tumor size was the smallest in luminal A while the largest in normal breast-like subtype (P <0.05). The positive rate of KI67 protein expression was lowest in luminal A and that highest in normal breast-like subtype (P <0.05). Invasive lobular carcinoma accounted for 54.5% of luminal B and invasive ductal carcinoma accounted the majority of other. The correlations of age, histological grade, node status and clinical stage to the classification were not found (P> 0.05). Recurrence of normal breast-like subtype was the highest in all (P <0.05). The 5-year-survival rates of luminal B and normal breast-like subtype were significantly lower than other (P <0.05).Conclusion: Immunohistochemistry classification of breast cancer might be helpful in indicating the biological behaviors of breast cancer and the prognosis of the patients.