Combined use of 18F-FDG PET/CT and MRI for response monitoring of breast cancer during neoadjuvant chemotherapy

Purpose

To explore the potential complementary value of PET/CT and dynamic contrast-enhanced MRI in predicting pathological response to neoadjuvant chemotherapy (NAC) of breast cancer and the dependency on breast cancer subtype.

Methods

We performed ¹⁸F-FDG PET/CT and MRI examinations before and during NAC. The imaging features evaluated on both examinations included baseline and changes in ¹⁸F-FDG maximum standardized uptake value (SUVmax) on PET/CT, and tumour morphology and contrast uptake kinetics on MRI. The outcome measure was a (near) pathological complete response ((near-)pCR) after surgery. Receiver operating characteristic curves with area under the curve (AUC) were used to evaluate the relationships between patient, tumour and imaging characteristics and tumour responses.

Results

Of 93 patients, 43 achieved a (near-)pCR. The responses varied among the different breast cancer subtypes. On univariate analysis the following variables were significantly associated with (near-)pCR: age (p?=?0.033), breast cancer subtype (p?<?0.001), relative change in SUVmax on PET/CT (p?<?0.001) and relative change in largest tumour diameter on MRI (p?<?0.001). The AUC for the relative reduction in SUVmax on PET/CT was 0.78 (95 % CI 0.68–0.88), and for the relative reduction in tumour diameter at late enhancement on MRI was 0.79 (95 % CI 0.70–0.89). The AUC increased to 0.90 (95 % CI 0.83–0.96) in the final multivariate model with PET/CT, MRI and breast cancer subtype combined (p?=?0.012).

Conclusion

PET/CT and MRI showed comparable value for monitoring response during NAC. Combined use of PET/CT and MRI had complementary potential. Research with more patients is required to further elucidate the dependency on breast cancer subtype.     

<Superscript>18</Superscript>F-FDG PET/CT for early prediction of response to neoadjuvant chemotherapy in breast cancer

Purpose  

The aim of this study was to prospectively evaluate ¹⁸F-FDG PET/CT in predicting response to neoadjuvant chemotherapy in large primary breast cancer.     

18F-FDG PET/CT评估三阴性乳腺癌新辅助化疗疗效的研究进展

三阴性乳腺癌（TNBC）是一种雌激素受体（ER）、孕激素受体（PR）及人表皮生长因子受体2（HER-2）表达均为阴性的乳腺癌亚型,常发生于绝经前的女性,具有预后较差、5年生存率低、侵袭性强、易复发及发生远处转移等特征。目前TNBC主要的治疗方法是手术与化疗,其中新辅助化疗的应用也越来越广泛。近年来,18F-FDG PET/CT在乳腺癌治疗评估中的价值已被广泛研究,PET/CT监测乳腺癌新辅助化疗疗效的价值已得到肯定。该文对18F-FDG PET/CT评估TNBC新辅助化疗疗效的研究进展进行综述。     

18F-FDG PET/CT radiomic predictors of pathologic complete response (pCR) to neoadjuvant chemotherapy in breast cancer patients

European Journal of Nuclear Medicine and Molecular Imaging - Pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) is commonly accepted as the gold standard to assess outcome after...     

HER2-positive breast cancer: 18F-FDG PET for early prediction of response to trastuzumab plus taxane-based neoadjuvant chemotherapy

Purpose

To investigate the value of ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET/CT) to predict a pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) in women with human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

Material and methods

Fifty-seven consecutive women with HER2-positive breast cancer, treated with trastuzumab plus taxane-based NAC, were prospectively included. Maximum Standardized Uptake Value of the primary tumor and axillary nodes were measured at baseline (PET₁.SUV_max) and after the first course of NAC (PET₂.SUV_max). Tumor metabolic volumes were assessed to determine Total Lesion Glycolysis (TLG). The tumor metabolic response (ΔSUV_max and ΔTLG) was calculated.

Results

In univariate analysis, negative hormonal receptor status (p?=?0.04), high tumor grade (p?=?0.03), and low tumor PET ₂ .SUV_max (p?=?0.001) were predictive of pCR. Tumor ΔSUV_max correlated with pCR (p?=?0.03), provided that tumors with low metabolic activity at baseline were excluded. ΔTLG did not correlate with pCR. In multivariate analysis, tumor PET₂.SUV_max?<?2.1 was the best independent predictive factor (Odds ratio =14.3; p?=?0.004) with both negative and positive predictive values of 76 %. Although the metabolic features of the primary tumor did not depend on hormonal receptor status, both the baseline metabolism and early response of axillary nodes were higher if estrogen receptors were not expressed (p?=?0.01 and p?=?0.03, respectively).

Conclusion

In HER2-positive breast cancer, very low tumor residual metabolism after the first cycle of NAC (SUV_max?<?2.1) was the main predictor of pCR. These results should be further explored in multicenter studies and incorporated into the design of clinical trials.     

The role of 18F-FDG PET/CT in evaluation of early response to neoadjuvant chemotherapy in patients with locally advanced breast cancer

We evaluated the role of 18F-FDG PET/CT for the assessment of response after two cycles of neo-adjuvant chemotherapy (NACT) for breast cancer. Twenty-three women with locally advanced breast cancer were included in this study. Early response to NACT was evaluated after two cycles using clinical examination, CT, and 18F-FDG PET/CT. Final histopathology following surgery after six cycles of NACT served as reference. Baseline PET/CT demonstrated a total of 26 lesions in 23 patients. The size of the primary tumor ranged from 1.90 cm to 11.60 cm, and the maximum value of the standardized uptake value of FDG (SUVmax) ranged from 3.6 to 38.6 (mean, 11.7). Post-chemotherapy PET/CT examinations were done after two cycles of NACT. The size of the primary tumor on follow-up PET/CT examinations ranged from 0.0 cm to 7.6 cm, and SUVmax ranged from 0.0 to 12.0 (mean, 3.96). On clinical, CT, and PET/CT examinations, 50% reduction in the parameters was taken as the cutoff value to differentiate between responders and non-responders. Post-NACT PET/CT demonstrated that 16 patients were responders and 7 non-responders. Among 16 responders on PET/CT scan, 14 were true positive and 2 were false positive when compared with histopathology. Among seven non-responder patients, six were true negative, and one was false negative. The sensitivity, specificity, and accuracy of PET/CT in detecting responders were 93%, 75%, and 87%, respectively. In conclusion, 18F-FDG PET/CT can differentiate responders from non-responders with high accuracy after two cycles of NACT in patients with LABC.     

18F-FDG PET/CT predicts survival in patients with inflammatory breast cancer undergoing neoadjuvant chemotherapy

Purpose

The objective of this study was to evaluate the role of ¹⁸F-FDG PET/CT in predicting overall survival in inflammatory breast cancer patients undergoing neoadjuvant chemotherapy.

Methods

Included in this retrospective study were 53 patients with inflammatory breast cancer who had at least two PET/CT studies including a baseline study before the start of neoadjuvant chemotherapy. Univariate and multivariate analyses were performed to assess the effects on survival of the following factors: tumor maximum standardized uptake value (SUVmax) at baseline, preoperatively and at follow-up, decrease in tumor SUVmax, histological tumor type, grade, estrogen, progesterone, HER2/neu receptor status, and extent of disease at presentation including axillary nodal and distant metastases.

Results

By univariate analysis, survival was significantly associated with decrease in tumor SUVmax and tumor receptor status. Patients with decrease in tumor SUVmax had better survival (P?=?0.02). Patients with a triple-negative tumor (P?=?0.0006), a Her2/neu-negative tumor (P?=?0.038) or an ER-negative tumor (P?=?0.039) had worse survival. Multivariate analysis confirmed decrease in tumor SUVmax and triple-negative receptor status as significant predictors of survival. Every 10 % decrease in tumor SUVmax from baseline translated to a 15 % lower probability of death, and complete resolution of tumor FDG uptake translated to 80 % lower probability of death (P?=?0.014). Patients with a triple-negative tumor had 4.11 times higher probability of death (P?=?0.004).

Conclusion

Decrease in tumor SUVmax is an independent predictor of survival in patients with inflammatory breast cancer undergoing neoadjuvant chemotherapy. Further investigation with prospective studies is warranted to clarify its role in assessing response and altering therapy.     

Early and delayed prediction of axillary lymph node neoadjuvant response by 18F-FDG PET/CT in patients with locally advanced breast cancer

Purpose

To determine the utility of ¹⁸F-FDG (FDG) PET/CT performed in an early and delayed phase during neoadjuvant chemotherapy in the prediction of lymph node histopathological response in patients with locally advanced breast cancer.

Methods

FDG PET/CT studies performed in 76 patients (mean age 53 years) at baseline (PET-1), after the second course of chemotherapy (PET-2) and after the last course of chemotherapy (PET-3) were prospectively analysed. Inclusion criteria were lymph node involvement detected by PET/CT and non-sentinel node biopsy before or after the baseline PET/CT scan. Following the recommendations of the 12th International Breast Conference (St. Gallen), the patients were divided into five subgroups in relation to biological prognostic factors by immunohistochemistry. For diagnosis visual and semiquantitative analyses was performed. Absence of detectable lymph node uptake on the PET-2 or PET-3 scan with respect to the PET-1 scan was considered metabolic complete response (mCR). Lymph nodes were histopathologically classified according the lymph node regression grade and in response groups as pathological complete response (pCR) or not pCR (type A/D or B/C of the Smith grading system, respectively). ROC analysis was performed to determine a cut-off value of Δ% SUV1–2 and SUV1–3 for prediction of nodal status after chemotherapy. An association between mCR and pCR was found (Cohen’s kappa analysis), and associations between phenotypes and metabolic behaviour and the final histopathological status were also found.

Results

Lymph node pCR was seen in 34 patients. The sensitivity, specificity, and positive and negative predictive values of PET-2 and PET-3 in establishing the final status of the axilla after chemotherapy were 52 %, 45 %, 50 % and 47 %, and 33 %, 84 %, 67 % and 56 %, respectively. No significant relationship was observed between mCR on PET-2 and PET-3 and pCR (p?=?0.31 and 0.99, respectively). Lymph node metabolism on PET-1 was not able to predict the final histopathological status, whereas basal carcinomas showed a higher rate of pCR (70.6 %) than the other groups (p?=?0.03).

Conclusion

FDG PET/CT seems to have limitations in both the early and delayed evaluation of lymph node status after chemotherapy, with reduced predictive values.     

比较MR扩散加权成像和葡萄糖PET/CT预测乳腺癌病人新辅助化疗的病理完全缓解

目的比较MR扩散加权成像(DWI)和18F-FDG PET/CT预测接受新辅助化疗的乳腺癌病人病理完全缓解。方法伴34个侵袭性乳腺癌肿块的34例妇女在化疗前后和手术前进行DWI和PET/CT。计算表观扩散系数(ADC)和标     

Comparison of diffusion-weighted MR imaging and FDG PET/CT to predict pathological complete response to neoadjuvant chemotherapy in patients with breast cancer

Objective  

To compare the use of diffusion-weighted MR imaging (DWI) and ¹⁸F-FDG PET/CT to predict pathological complete response (pCR) in breast cancer patients receiving neoadjuvant chemotherapy.     

Early prediction of response to chemotherapy in metastatic breast cancer using sequential 18F-FDG PET.

Chemotherapy is currently the treatment of choice for patients with high-risk metastatic breast cancer. Clinical response is determined after several cycles of chemotherapy by changes in tumor size as assessed by conventional imaging procedures including CT, MRI, plain film radiography, or ultrasound. The aim of this study was to evaluate the use of sequential 18F-FDG PET to predict response after the first and second cycles of standardized chemotherapy for metastatic breast cancer. METHODS: Eleven patients with 26 metastatic lesions underwent 31 (18)F-FDG PET examinations (240-400 MBq of 18F-FDG; 10-min 2-dimensional emission and transmission scans). Clinical response, as assessed by conventional imaging after completion of chemotherapy, served as the reference. 18F-FDG PET images after the first and second cycles of chemotherapy were analyzed semiquantitatively for each metastatic lesion using standardized uptake values (SUVs) normalized to patients' blood glucose levels. In addition, whole-body 18F-FDG PET images were viewed for overall changes in the 18F-FDG uptake pattern of metastatic lesions within individual patients and compared with conventional imaging results after the third and sixth cycles of chemotherapy. RESULTS: After completion of chemotherapy, 17 metastatic lesions responded, as assessed by conventional imaging procedures. In those lesions, SUV decreased to 72% +/- 21% after the first cycle and 54% +/- 16% after the second cycle, when compared with the baseline PET scan. In contrast, 18F-FDG uptake in lesions not responding to chemotherapy (n = 9) declined only to 94% +/- 19% after the first cycle and 79% +/- 9% after the second cycle. The differences between responding and nonresponding lesions were statistically significant after the first (P = 0.02) and second (P = 0.003) cycles. Visual analysis of 18F-FDG PET images correctly predicted the response in all patients as early as after the first cycle of chemotherapy. As assessed by 18F-FDG PET, the overall survival in nonresponders (n = 5) was 8.8 mo, compared with 19.2 mo in responders (n = 6). CONCLUSION: In patients with metastatic breast cancer, sequential 18F-FDG PET allowed prediction of response to treatment after the first cycle of chemotherapy. The use of 18F-FDG PET as a surrogate endpoint for monitoring therapy response offers improved patient care by individualizing treatment and avoiding ineffective chemotherapy.     

重复PET/CT的代谢反应预测食管癌新辅助化疗的病理学缓解

目的据报道,在新辅助化疗过程中或之后行正电子发射体层摄影(PET)示肿瘤18F-脱氧葡萄糖(FDG)摄取减低,可预测食管癌的病理学缓解。我们的目的是在前瞻性临床实验中应用标准化新辅助化疗方案来确定代谢反应是否可预测病理学缓解。方法一项非随机临床试验,包括接受治疗的潜在可治愈的食管癌病人。使用标准化化疗方案(奥沙利铂和5-氟尿嘧啶两个疗程)。化疗前行PET/CT,且在第2疗程开始后24～28d复查PET/CT。结果入选48例,平均年龄65岁,男性37例。应用最大标准摄取值(SUVmax)(42%)中位百分比降低来定义代谢反应,病理学缓解可见于71%(17/24)的代谢反应,无反应者为33%(8/24;P=0.009,敏感度68%,特异度70%)。病理学缓解可见于81%(13/16)具有完全代谢反应的病例和38%不完全代谢反应的病例(12/32;P=0.0042,敏感度52%,特异度87%),但无基于组织学的显著效应。结论代谢反应与病理学缓解之间具有显著相关性,但预测病理学缓解的准确性仍相对较低。要点①PET/CT可预测食管癌病人其肿瘤对化疗的反应。②采用标准化化疗的前瞻性研究。③PET/CT表现和疾病反应之间具有显著相关性。④然而预测病理学缓解的准确性仍相对较低。