Breast cancer response to neoadjuvant chemotherapy: predictive markers and relation with outcome

The aim of this study was to provide a better insight into breast cancer response to chemotherapy. Chemotherapy improves outcome in breast cancer patients. The effect of cytotoxic treatment cannot be predicted for individual patients. Therefore, the identification of tumour characteristics associated with tumour response and outcome is of great clinical interest. We studied 97 patients, who received anthracycline-based neoadjuvant chemotherapy. Tumour samples were taken prior to and after chemotherapy. We quantified the response to chemotherapy clinically and pathologically and determined histological and molecular tumour characteristics. We assessed changes in the expression of Bcl-2, ER, P53 HER2 and Ki-67. Association with response and outcome was tested for all parameters. The experimental results showed 15 clinical (17%) and three (3%) pathological complete remissions. There were 18 (20%) clinical vs 29 (33%) pathological nonresponders. The expression of most markers was similar before and after chemotherapy. Only Ki-67 was significantly decreased after chemotherapy. Factors correlated with response were: large tumour size, ER negativity, high Ki-67 count and positive P53 status. Tumour response and marker expression did not predict disease-free or overall survival. In conclusion, clinical and pathological response assessments are poorly associated. Proliferation decreases significantly after chemotherapy. ER negativity and a high proliferation index are associated with better response. HER2 status does not predict response, and outcome is not related to tumour response.     

Molecular markers of response and toxicity to FOLFOX chemotherapy in metastatic colorectal cancer

Background:

To investigate three genetic alterations (TP53 mutation, Kras mutation and microsatellite instability (MSI)) and three polymorphisms (methylene tetrahydrofolate reductase (MTHFR) C677T, excision repair cross complementing group 1 (ERCC1)-118 and X-ray repair cross complementing group 1 (XRCC1)-399) for their ability to predict response, survival and toxicity to FOLFOX first line chemotherapy in the treatment of metastatic colorectal cancer (mCRC).

Methods:

Tumour tissues from 118 mCRC patients who underwent FOLFOX treatment from three successive phase II trials were evaluated for mutations in TP53 (exons 5–8) and Kras (codons 12 and 13) and for MSI using PCR-based analysis. Genotyping for common single nucleotide polymorphisms in the MTHFR (codon 677), ERCC1 (codon 118) and XRCC1 (codon 399) genes was also carried out using PCR techniques. These genetic markers were correlated with clinical response, survival and toxicity to treatment.

Results:

Patients with the T allele of ERCC1-118 showed significantly worse progression-free survival in univariate analysis (HR=2.62; 95% CI=1.14–6.02; P=0.02). None of the genetic alterations or polymorphisms showed significant association with clinical response to FOLFOX. The MTHFR, ERCC1 and XRCC1 polymorphisms showed no associations with overall haematological, gastrointestinal or neurological toxicity to FOLFOX, although MTHFR 677 TT genotype patients showed a significantly higher incidence of grade 3 or 4 diarrhoea (26%) compared with CC or CT genotype patients (6%, P=0.02).

Conclusions:

The ERCC1-118 and MTHFR C677T polymorphisms were associated with progression and severe diarrhoea, respectively, after FOLFOX treatment in mCRC. Although our findings require confirmation in large prospective studies, they reinforce the concept that individual genetic variation may allow personalized selection of chemotherapy to optimize clinical outcomes.     

Predictive value of thymidylate synthase expression in advanced colorectal cancer patients receiving fluoropyrimidine-based chemotherapy: evidence from 24 studies

The published data about thymidylate synthase (TS) expression and its predictive value in advanced colorectal cancer (CRC) patients receiving fluoropyrimidine-based chemotherapy seemed inconclusive. To derive a more precise estimation of the relationship, a metaanalysis was performed. Studies have been identified by searching PubMed and Embase. Inclusion criteria were advanced CRC patients, received fluoropyrimidine-based chemotherapy and evaluation of TS expression and overall response rate (ORR). The relative ratio (RR) for ORR in patients with low-TS expression over those with high-TS expression with 95% confidence interval (CI) was calculated for each study as an estimation of the predictive effect of TS. A total of 24 studies including 1,112 patients were involved in this metaanalysis. The overall RR was 2.20 (95% CI, 1.82-2.66; p = 0.000). For studies evaluating TS expression in metastatic lesions, the pooled RR was 3.23 (95% CI, 2.27-4.59; p = 0.000); for studies testing TS expression in primary lesions, a pooled RR of 1.89 (95% CI, 1.45-2.48; p = 0.000) was estimated. Focusing the analysis on immunohistochemistry (IHC)-based or RTPCR-based assessments, the pooled RR was 1.83 (95% CI, 1.44-2.34; p = 0.000) and 2.96 (95% CI, 2.07-4.22; p = 0.000), respectively. The results indicated that low-TS expression tumors in advanced CRC patients were more sensitive to fluoropyrimidine-based chemotherapy. Subgroup analyses indicated that the predictive value of TS expression evaluated in metastases was more prominent than that of primary lesions, and that TS expression tested by RTPCR was also of greater predictive value than by IHC.     

Predictors of response to subsequent chemotherapy in platinum pretreated ovarian cancer: A multivariate analysis of 704 patients

BACKGROUND: The probability of response to chemotherapy following platinumbased treatment in ovarian cancer has usually been related tothe ‘platinum-free interval’. However, in a recentEuropean–Canadian trial of paclitaxel, serous histology,tumor bulk, and hemoglobin, but not treatment free interval,were predictors of response. To determine if these observationswere unique to this study (or this drug), data from other activeagents given as second- or third-line treatment in ovarian cancerwere obtained and analyzed. METHODS: In the first part of the study, results of trials in 1185 platinumpretreated ovarian cancer patients were obtained on six agents:paclitaxel, epirubicin, docetaxel, carboplatin, irinotecan,and gemcitabine. Response results according to histology, baselinehemoglobin, tumor size and time from last chemotherapy weredetermined for each agent and the Cochran-Mantel-Haenszel procedurewas used to obtain an overall assessment of significance foreach factor. In the second part of the study, individual datafrom 704 patients in four studies (three agents: paclitaxel,docetaxel and epirubicin) were pooled for univariate and multivariateanalysis of factors predictive of response. RESULTS: In the analysis of results of individual agents all factorsexamined were significant predictors of response: serous histology(P = 0.001), tumor size     

The relationship of the neo-angiogenic marker, endoglin, with response to neoadjuvant chemotherapy in breast cancer

Endoglin (CD105) is upregulated in endothelial cells of tissues undergoing neovascularisation. A greater number of CD105-positive vessels predicts poor survival in breast cancer. We examine whether CD105 expression predicts response to neoadjuvant chemotherapy. Fifty-seven women (median age 50 years, range 29-70) received neoadjuvant chemotherapy for operable breast cancer. Immunohistochemical staining using monoclonal antibodies to CD105 and CD34 was performed on pretreatment biopsies and post-treatment surgical specimens. Individual microvessels were counted in 10 random fields at x 200 magnification. Median counts were correlated with clinical and pathological response using the Mann-Whitney U-test. Forty-five out of fifty-seven patients (79%) responded clinically, 22 (39%) responded pathologically. On pretreatment biopsies, clinical responders had significantly lower median CD105-positive vessel counts than nonresponders (median counts 5 and 9.3/high-power field (hpf), median difference=4.0/hpf, 95% CI 0.5-8.0/hpf, P=0.02). For pathological responders and nonresponders, median counts were 4.8 and 5.5/hpf (median difference -0.5/hpf, 95% CI=-2.5-2.0/hpf, P=0.77). CD34 expression (total microvessel density) did not correlate with response. Pretreatment CD105 expression predicts for clinical response to chemotherapy, with a lower initial count being favourable. Patients with high baseline new vessel counts or increased counts after conventional therapy may benefit from additional antiangiogenic therapy.     

STAT1 activation in squamous cell cancer of the oral cavity: a potential predictive marker of response to adjuvant chemotherapy

BACKGROUND: For patients with squamous cell carcinoma of the oral cavity, both locoregional and distant recurrences are common, and an appropriate adjuvant treatment modality has yet to be defined. Thus, there is an urgent need to identify novel molecular markers with potential prognostic and/or predictive value to improve treatment outcome in these patients. This retrospective study was designed to investigate the predictive and/or prognostic value of STAT1 activation in squamous cell carcinoma of the oral cavity. METHODS: STAT1 expression and subcellular localization was examined immunohistochemically on a tissue microarray of paraffin-embedded tumor specimens from 89 patients who underwent surgical treatment in the period between 1980 and 1997. A nuclear staining score of greater than 35% was defined as high STAT1 activation. RESULTS: According to study criteria, 18% of analyzed tumor samples exhibited high STAT1 activation. High STAT1 activation was associated with negative lymph node status. Moreover, in the subgroup of patients who received chemotherapy, high nuclear STAT1 staining in the tumor was associated with good prognosis. CONCLUSIONS: This is the first report demonstrating the potential predictive value of STAT1 activation status in patients with squamous cell cancer of the oral cavity. If confirmed in large prospective trials, this molecular marker could help in guiding therapeutic decisions in these patients.     

Glutathione S-transferase activity in epithelial ovarian cancer: Association with response to chemotherapy and disease outcome

Background: Conflicting data have been reported about the associationbetween glutathione S-transferase (GST), a family of proteins implicated indetoxification of cytotoxic drugs in human ovarian in vitro models, andresponse to chemotherapy and prognosis in ovarian cancer patients. The aim ofthis study was to analyze the possible clinical role of GST activity in alarge series of primary ovarian cancer patients.Patients and methods: The study included a large series of primaryuntreated ovarian cancer patients who underwent cytoreductive surgery andchemotherapy and who were followed up in a single institution. GST activitylevels were assessed in tumor extracts by using a biochemical assay. A cut-offof 250 units of enzymatic activity was chosen according to the receiveroperating characteristics (ROC) curve.Results: GST activity levels were distributed in an asymmetrical manner(median: 266 units; range: 4–918 units) and did not seem to beassociated with stage, histopathological grading, ascites, or residual tumorafter surgery. Higher GST activity levels were found in patients who respondedto chemotherapy (median: 298 units, range: 50–691) than in those whoresponded only partially (median: 227 units, range: 19–747) or not atall to chemotherapy (median: 246 units, range: 4–811) (H = 7.02, P =0.029). Moreover, the percentage of cases with >250 units was significantlyhigher among complete responders (66%) than partial responders(37%) or non-responders (48%) (² = 7.32;P = 0.025). When multivariate analysis, including clinico-pathologicalparameters and GST activity status as predictors of response to chemotherapy,was carried out, residual tumor, stage and GST status retained independentpredictive value. Patients with high GST activity had more favourableprognosis than those with low GST activity. The median PFS was 42 months forpatients with high GST activity compared to 17 months for those with low GSTactivity (P = 0.037). The median overall survival was 72 months forhigh-GST-activity and42 months for low-GST-activity patients (P = 0.043). Substantially similarresults were obtained in the subgroup of stage II–III–IV ovariancancer patients. Multivariate analysis including the clinico-pathologicalparameters and GST activity status was performed in stage III–IV ovariancancer patients: Stage IV disease, residual tumor >2 cm, the presence ofascites and low GST activity status retained independent negative prognosticroles.Conclusion: A direct association between high GST activity and a betterclinical outcome in terms of response to chemotherapy and survival has beenobserved in a large series of primary untreated ovarian cancer patients. Theseresults, which are contrary to the expectations raised by in vitro studies,emphasize the need for caution when translating in vitro-generated hypothesesto the clinical setting.     

Response to chemotherapy has predictive value for further survival of patients with advanced non-small cell lung cancer: 10 years experience of the european lung cancer working party

The aim of this study was the assessment of the predictive value for survival of an antitumoral response to three courses of chemotherapy in association with various pretreatment characteristics in patients with non-resectable non-small cell lung cancer treated by cisplatin- (or carboplatin)-based combination regimens. Patients considered for this study were eligible patients with advanced non-small cell lung cancer registered in one of the seven trials conducted by the European Lung Cancer Working Party from December 1980 to August 1991. All these trials tested chemotherapy regimens with platinum derivatives (cisplatin and/or carboplatin). In this population of 1052 eligible patients, 752 were assessed in this analysis. Data were prospectively collected on 23 pretherapeutic variables and objective response after three chemotherapy cycles. The predictive value of response to chemotherapy on survival (measured from the time of response assessment i.e. 12 weeks after registration in the trial) was studied by univariate analysis as well as by multivariate methods (adjustment of the impact of several covariates simultaneously on the dependent variable) with adjustment for the pretreatment prognostic variables. After three cycles of chemotherapy, the global estimated median survival time was 24 weeks with a 95% confidence interval of 22–25 weeks. By univariate analysis, we identified an objective response to chemotherapy as a highly significant discriminant marker (P < 0.0001) for further survival with estimated median survival times of 41 weeks (95% CI: 38–46) and 19 weeks (95% CI: 17–20), respectively, for the responding and non-responding patients. In a Cox regression model fitted to the data using a forward stepwise procedure, this variable was the first selected explanatory variable. Its effect was adjusted by the introduction in the model of initial disease extent, Karnofsky performance status, serum calcium level and white blood cell count. These results were consistent with those obtained by application of recursive partitioning and amalgamation algorithms (RECPAM) which led to a classification of the patients into three homogeneous subgroups. Our results, using a classical Cox regression model consistent with those highlighted by application of a RECPAM analysis, found an objective response to chemotherapy to be a predominant predictive factor for further survival, although it did not allow any conclusion about a causal relationship. The RECPAM results led to a classification of the patients into three subgroups which needs to be validated in other series.     

Serum soluble Fas levels and prediction of response to platinum-based chemotherapy in epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is treated mainly by platinum-based combination chemotherapy. Chemotherapy induces apoptosis in which the Fas/Fas ligand pathway is important. Serum soluble Fas (sFas) is a biomarker of this pathway and functionally inhibits Fas-/FasL-mediated apoptosis. In this study, we have investigated the role of sFas in prediction of response to chemotherapy in EOC. Thirty-five patients were recruited and their serum sFas levels were estimated by ELISA at 4 time points-preoperative (sFas1), postoperative (sFas2), midchemotherapy (sFas3) and at the end of chemotherapy (sFas4). The response to chemotherapy was documented clinically, radiologically and by CA-125 levels, based on which, 2 groups were identified: primary chemosensitive (n = 24) and primary chemoresistant (n = 11). Based on the disease status at last follow-up, 2 groups were identified: No Evidence of Disease (n = 15) and Evidence of Disease (n = 20). The primary chemoresistant tumors showed significantly higher median sFas2 levels (p = 0.033) with the sFas2/sFas1 ratio > or =1 (p = 0.001). A multivariate Cox proportional hazards regression model identified sFas2/sFas1 ratio as a significant factor for the prediction of response to platinum-based chemotherapy (p = 0.011). Receiver operating characteristic (ROC) analysis showed that at a ratio of 1.2, sFas2/sFas1 achieved a sensitivity of 82% and specificity of 100% for prediction of chemotherapeutic response. sFas2/sFas1 and sFas3/sFas1 ratio was also higher in patients with evidence of disease (p = 0.018 and p = 0.028, respectively). Progression-free survival rates in patients with sFas2/sFas1 ratio <1 exceeded those with ratio > or =1 (p = 0.004). In conclusion, serum sFas is a useful biomarker for predicting response to platinum-based chemotherapy in EOC.     

Predictive value of BRCA1/2 mRNA expression for response to neoadjuvant chemotherapy in BRCA‐negative breast cancers

It is well known that BRCA1 and BRCA2 play a central role in DNA repair, but the relationship between BRCA1 and BRCA2 mRNA expression and response to neoadjuvant chemotherapy in sporadic breast cancer patients has not been well established. Here, we investigate the association between BRCA1 or BRCA2 mRNA expression levels and pathological response in 674 BRCA1/2 mutation‐negative breast cancer patients who received neoadjuvant chemotherapy. BRCA1 and BRCA2 mRNA expression were assessed using quantitative real‐time polymerase chain reaction in core biopsy breast cancer tissue obtained prior to the initiation of neoadjuvant chemotherapy. A total 129 patients (19.1%) achieved pathological complete response (pCR) after neoadjuvant chemotherapy. Among patients treated with anthracycline‐based chemotherapy (n = 531), BRCA1 mRNA low expression patients had a significantly higher pCR rate than intermediate or high BRCA1 mRNA expression groups (24.6% vs 16.8% or 14.0%, P = .031) and retained borderline significance (OR = 1.54, 95% CI = 0.93‐2.56, P = .094) in multivariate analysis. Among the 129 patients who received a taxane‐based regimen, pCR rate showed no differences in BRCA1 low, intermediate, and high mRNA level subgroups (19.6%, 26.8% and 21.4%, respectively; P = .71). BRCA2 mRNA level was not associated with pCR rate in the anthracyline‐based treated subgroup (P = .60) or the taxane‐based regimen subgroup (P = .82). Taken together, our findings suggested that BRCA1 mRNA expression could be used as a predictive marker in BRCA1/2 mutation‐negative breast cancer patients who received neoadjuvant anthracycline‐based treatment.     

Genomic expression,chemotherapy response,and molecular targets in soft tissue sarcomas of the extremities: Promising strategies for treatment selection

Neoadjuvant or adjuvant therapy in soft tissue sarcomas is still controversial, especially in regards to the use of chemotherapy. The identification of predictive factors is crucial to avoid the use of chemotherapy in patients with tumors that carry genetic characteristics associated with resistance. Focusing on gene expression data, we performed a review of the actual state of knowledge in molecular predictive factors for chemotherapy response and new targets of therapy in extremity sarcomas. J. Surg. Oncol. 2010;101:92–96. © 2009 Wiley‐Liss, Inc.     

Predictive value of baseline 18F-FDG PET/CT and interim treatment response for the prognosis of patients with diffuse large B-cell lymphoma receiving R-CHOP chemotherapy

The present study aimed to investigate the prognostic value of baseline ¹⁸F-FDG PET/CT quantitative parameters and interim treatment response, and to assess whether the combination of these could improve the predictive efficacy in patients with diffuse large B-cell lymphoma (DLBCL) receiving R-CHOP chemotherapy. PET/CT images and clinical data of 64 patients with DLBCL who had undergone ¹⁸F-FDG PET/CT scan before and after 3 or 4 cycles of R-CHOP chemotherapy were retrospectively reviewed. The quantitative parameters including standardized uptake value (SUV), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum diameter of the maximum lesion (Dmax) were measured on baseline PET/CT images. Cox proportional hazards model was used to evaluate the influence of baseline PET/CT parameters, clinical indicators and interim treatment response on prognosis. Survival analysis was performed using Kaplan-Meier method. Receiver operating characteristic (ROC) curve analysis was performed to estimate the predictive efficacy of the combination of baseline PET/CT parameters and interim treatment response. Ann Arbor stage, International Prognostic Index (IPI), lactate dehydrogenase (LDH), necrosis, MTVmax, TLGmax, Dmax and interim treatment response showed association with 2-year progression-free survival (PFS, P<0.05). LDH, necrosis, MTVmax, MTVsum, TLGmax, TLGsum, Dmax and interim treatment response showed association with 2-year overall survival (OS, P<0.05). Ann Arbor stage, Dmax and interim treatment response were found to be independent predictors of 2-year PFS (P<0.05), while Dmax and interim treatment response were found to be independent predictors of 2-year OS (P<0.05). The PFS and OS curves of Dmax <5.7 cm group and Dmax ≥5.7 cm group, complete response (CR) group and non-CR group were significantly different, respectively (P<0.05). The baseline ¹⁸F-FDG PET/CT parameters and interim treatment response have important prognostic values in DLBCL patients who received R-CHOP chemotherapy. Combined application of Dmax and interim treatment response improved the predictive efficacy of 2-year PFS. It may be helpful to identify patients who are at high-risk of relapse and to guide early clinical intervention of these patients.     

Sustained response of sarcomatoid renal-cell carcinoma to MAID chemotherapy: Case report and review of the literature

The sarcomatoid variant of renal-cell carcinoma (SRCC), a clinicallyaggressive subtype of renal parenchymal tumors, is typically resistant tosystemic treatments and carries a poor prognosis. The authors report a caseof a 57-year-old male with advanced SRCC who had a durable complete responseafter MAID (mesna, adriamycin, ifosfamide and dacarbazine) chemotherapy, andremains free of disease four years after completing treatment. To theauthors' knowledge, this is the first report of a remission from MAIDchemotherapy in SRCC. A review of published literature revealed occasionalresponses after systemic chemotherapy. Notably, all responses were seen withdoxorubicin containing regimens, suggesting that doxorubicin is a criticalcomponent in chemotherapy regimens for SRCC.     

Clinical and pathological predictors of the response to neoadjuvant anthracycline chemotherapy in locally advanced breast cancer

Purpose The aim of this study is to determine clinical and histopathological characteristics correlated to responsiveness to anthracycline-based neoadjuvant chemotherapy in breast cancer. Patients and methods We studied primary tumor specimens with local advanced breast cancer from 40 patients. Patients received anthracycline-based chemotherapy. Neoadjuvant regimen consisted in 600 mg/m² 5-fluorouracil, 60 mg/m² doxorubicin, and 600 mg/m² cyclophosphamide (FAC). The World Health Organization criteria were used to classify the tumors. We performed immunohistochemical staining for ER, PgR, HER-2, PCNA (proliferation cell nuclear antigen), Ki-67, p53, and Bcl-2. Clinical and histopathological characteristics were associated with clinical response and histopathological changes induced by chemotherapy. Results The mean age was 47±14 yr. Twenty-three percent of patients were in stage IIB and 77% were in stages IIIA and IIIB. Seven percent of patients had progression of the disease. Stable disease was observed in 42% of patients and 45% had partial response. Only 7% of patients had a complete response. Factors associated with a better and major percentage of clinical response were the administration of doxorubicin-based chemotherapy, administration of more than three cycles, clinical N1, atypia, more than 10 mitosis per high-power field, moderate to severe SBR grade, and a major index of cellular proliferation. Conclusion We found that tumors with large volumes, N2 node status, low cellular proliferation rate, positive immunoreactivity to p53, and low differentiation grade have a lower response to neoadjuvant chemotherapy with anthracycline. These patients could benefit from a different chemotherapy scheme to obtain a better control and resection.     

乳腺癌新辅助化疗 PCR 与生存获益的研究进展

乳腺癌的治疗理念已经从局部疾病转变为全身疾病,随着近几年的研究,新辅助化疗的治疗方式被应用的越来越广泛,它不仅可以缩小肿瘤的大小,达到可手术切除的目的,而且可以使有保乳意愿的年轻患者实现保乳,同时也间接的起到体内药敏试验的效果,更好地指导手术后的化疗方案选择。新辅助化疗后病理完全缓解被认为是长期生存获益的替代指标,受到越来越多的关注。     

A patient with cholangiocarcinoma demonstrating pathologic complete response to chemotherapy: exploring the role of neoadjuvant therapy in biliary tract cancer

The role of neoadjuvant chemotherapy and/or radiation for localized or potentially resectable cholangiocarcinoma (CCA) has not been well established. We present here the case of a patient with an extrahepatic CCA who achieved a pathologic complete response after undergoing preoperative gemcitabine-based chemotherapy, without sequential or concurrent use of radiation. Further evaluation of neoadjuvant strategies in CCA, including not only combined-modality therapy but also the use of chemotherapy exclusively, is warranted in prospective study design.     

Survivin 和 MRP1 在宫颈鳞癌中的表达及其对新辅助化疗敏感性的预测研究

目的：探讨新辅助化疗前后Survivin、MRPl在宫颈鳞癌组织中的表达及其与化疗敏感性的关系。方法：采用免疫组化sP法对38例宫颈鳞癌患者新辅助化疗（NACT）前后MRPl、Survivin的表达水平进行检测。结果：NACT前Survivin的阳性表达率（63．16％）显著高于NACT后（39．47％）（P〈0．05）,且NACT前Sur—vivin表达阴性者化疗有效率（92．86％）高于表达阳性者（62．50％）（P〈0．05）。Survivin的表达水平与宫颈鳞癌的分化程度相关（P〈0．05）,但与年龄、临床分期不相关（P〉0．05）。新辅助化疗前后MRPl在宫颈鳞癌中的阳性表达率分别为84．21％和92．11％,两者间无显著性差异（P〉0．05）,且化疗前MRPl表达阴性者与表达阳性者化疗有效率分别为83．33％、71．88％,两者问无显著性差异（P〉0．05）。MRPl的表达与宫颈癌的临床分期、分化程度、年龄均不相关（P〉0．05）。结论：Survivin、MRPl在宫颈鳞癌组织中均有较高的表达水平,但只有Survivin的表达水平与NACT疗效具有显著的相关性,Survivin的表达水平可作为预测宫颈鳞癌对化疗敏感性的指标。     

MTHFR和ABCG2单核苷酸多态性对晚期结直肠癌—线化疗疗效的预测作用

目的:探讨亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)和乳腺癌耐药蛋白(breast cancer resistance protein,BCRP/ABCG2)基因单核苷酸多态性(single nucleotide polymorphism,SNP)对晚期结直肠癌一线化疗疗效的预测作用.方法:采用基因测序法检测154例接受FOLFOX、XELOX或FOLFIRI方案一线化疗的晚期结直肠癌患者外周血MTHFR 677C＞T、MTHFR 1298A＞C、ABCG2 34G＞A和ABCG2 421C＞A这4个位点的SNP,结合临床特征,分析其与近期疗效、无进展生存(progression-free survival,PFS)和总生存(overall survival,OS)之间的关系.结果:154例患者接受一线化疗的有效率为31.8％,中位PFS为8.1个月,中位OS为30.7个月.MTHFR和ABCG2 SNP与近期疗效和OS无显著相关性(P＞0.05).含3～4个优势基因型(MTHFR 677C/C、MTHFR 1298A/A、ABCG2 34G/A或A/A及ABCG2 421C/A或A/A)患者的中位PFS较含0～2个优势基因型患者的显著延长(分别为9.8和7.5个月,P=0.013).COX多因素分析结果显示,优势基因型数目(P=0.017)和原发灶是否根治切除(P=0.010)是影响PFS的独立因素.单因素和多因素分析结果均显示,原发灶是否根治切除是影响OS的独立因素(P=0.000,P=0.000).结论:联合分析MTHFR和ABCG2 SNP对一线化疗治疗晚期结直肠癌的PFS有一定的预测作用,原发灶是否根治切除是影响PFS和OS的独立因素.