Assessment of response of neoadjuvant chemotherapy in carcinoma breast patients by high-frequency ultrasound

Aim

To assess the response of neoadjuvant chemotherapy in carcinoma breast patients by high-frequency ultrasound.

Material and Method

The current single blind, observational study was conducted at rural tertiary healthcare center of Acharya Vinoba Bhave Rural Hospital from October 2018 to Sept 2020. We incorporated breast cancer patients with TNM stages IIIA and IIIB who received neoadjuvant chemotherapy with Cyclophosphamide/Adriamycin/5 FU and Paclitaxel respectively followed by standard surgical procedure modified radical mastectomy. Successive ultrasound examination of the breast malignancy and the axilla was done after 21 days of either of any neoadjuvant chemotherapy for 3 cycles. Assessment of response to neoadjuvant chemotherapy was applied in terms of reduction in the breast tumour volume on ultrasound and percentage of tumour response calculated by Response Evaluation Criteria for Solid Tumours (RECIST). Data were analysed using SPSS version 24.0.

Results

Higher frequency of patients was invasive ductal breast cancer. In our study, Paclitaxel group showed better response in terms of CR and PR than CAF group. Our study noticed a consistent decrement in tumour volume after every cycle of either CAF or Paclitaxel NACT. Axillary ultrasound was able to predict the response of axillary lymph nodes in terms of increase or decrease in number and morphological changes after 3 cycles of NACT with similarity on final histopathology.

Conclusion

It can be concluded from the results of the present study that high-frequency ultrasound is appropriate tool for assessment of response of primary breast malignancy and lymphnode metastasis in the axilla after neoadjuvant chemotherapy.

Early detection of chemotherapy-refractory patients by monitoring textural alterations in diffuse optical spectroscopic images

PURPOSE

Changes in textural characteristics of diffuse optical spectroscopic (DOS) functional images, accompanied by alterations in their mean values, are demonstrated here for the first time as early surrogates of ultimate treatment response in locally advanced breast cancer (LABC) patients receiving neoadjuvant chemotherapy (NAC). NAC, as a standard component of treatment for LABC patient, induces measurable heterogeneous changes in tumor metabolism which were evaluated using DOS-based metabolic maps. This study characterizes such inhomogeneous nature of response development, by determining alterations in textural properties of DOS images apparent at early stages of therapy, followed later by gross changes in mean values of these functional metabolic maps.

METHODS

Twelve LABC patients undergoing NAC were scanned before and at four times after treatment initiation, and tomographic DOS images were reconstructed at each time. Ultimate responses of patients were determined clinically and pathologically, based on a reduction in tumor size and assessment of residual tumor cellularity. The mean-value parameters and textural features were extracted from volumetric DOS images for several functional and metabolic parameters prior to the treatment initiation. Changes in these DOS-based biomarkers were also monitored over the course of treatment. The measured biomarkers were applied to differentiate patient responses noninvasively and compared to clinical and pathologic responses.

RESULTS

Responding and nonresponding patients demonstrated different changes in DOS-based textural and mean-value parameters during chemotherapy. Whereas none of the biomarkers measured prior the start of therapy demonstrated a significant difference between the two patient populations, statistically significant differences were observed at week one after treatment initiation using the relative change in contrast/homogeneity of seven functional maps (0.001<p<0.049), and mean value of water content in tissue (p=0.010). The cross-validated sensitivity and specificity of these parameters at week one of therapy ranged between 80%-100% and 67%-100%, respectively. Higher levels of statistically significant differences were exhibited at week four after start of treatment, with cross-validated sensitivities and specificities ranging between 80% and 100% for three textural and three mean-value parameters. The combination of the textural and mean-value parameters in a "hybrid" profile could better separate the two patient populations early on during a course of treatment, with cross-validated sensitivities and specificities of up to 100% (p=0.001).

CONCLUSIONS

The results of this study suggest that alterations in textural characteristics of DOS images, in conjunction with changes in their mean values, can classify noninvasively the ultimate clinical and pathologic response of LABC patients to chemotherapy, as early as one week after start of their treatment. This provides a basis for using DOS imaging as a tool for therapy personalization.

Elevated thymidine kinase 1 in serum following neoadjuvant chemotherapy predicts poor outcome for patients with locally advanced breast cancer

Patients with locally advanced breast cancer (LABC) commonly have an unfavorable prognosis. A molecular predictor for the identification of at-risk patients is urgently required. Thymidine kinase 1 in serum (S-TK1) is an enzyme involved in the synthesis of DNA precursors. In studies using immunohistochemistry, it was reported to be a more useful proliferation marker than Ki-67 in breast, lung and colorectal carcinoma. In the present study, we extended the research of prior breast carcinoma studies by postulating that in patients with LABC, overexpression of S-TK1 following neoadjuvant chemotherapy predicts cancer outcome. An experimental design consisting of 48 patients with LABC was prospectively constructed and analyzed. All patients received neoadjuvant chemotherapy and definitive surgical therapy. Study homogeneity was maintained by standardized treatment, surveillance and compliance protocols. The S-TK1 concentration was detected using the anti-TK1 chicken IgY antibody, using a dot-blot immuno-assay. After a median follow-up of 30 months, the results indicated a statistically significant trend (unadjusted). Patients with high S-TK1 overexpression had a significantly higher incidence of recurrence (P=0.006) and cancer death (P= 0.0128) than those with low S-TK1 overexpression. A multivariate analysis provided identical results. The hazards ratio for developing recurrence in patients with higher S-TK1 expression was 6-7 times higher than the hazards ratio in patients with lower expression. In conclusion, our results indicate that a high S-TK1 concentration in sera from LABC patients receiving neoadjuvant chemotherapy is predictive of cancer outcome.

Synergy of nab-paclitaxel and bevacizumab in eradicating large orthotopic breast tumors and preexisting metastases

INTRODUCTION

Patients with metastatic disease are considered incurable. We previously showed that nabpaclitaxel (nanoparticle albumin-embedded paclitaxel) combined with anti-vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, eradicates orthotopic small-sized breast tumors and metastasis. Here, we assessed this therapy in two models of advanced (450-600 mm(3)) breast tumors and delineated VEGF-A-dependent mechanisms of tumor resistance.

METHODS

Mice with luciferase-tagged advanced MDA-MB-231 and MDA-MB-435 tumors were treated with saline, nab-paclitaxel (10 or 30 mg/kg), bevacizumab (4 mg/kg), or combined drugs. Lymphatic and lung metastases were measured by luciferase assay. Proinflammatory and survival pathways were measured by ELISA, Western blot and immunohistochemistry.

RESULTS

Nab-paclitaxel transiently suppressed primary tumors by 70% to 90% but had no effect on metastasis. Coadministration of bevacizumab increased the response rate to 99%, including 71% of complete responses in MDA-MB-231-bearing mice treated concurrently with 30 mg/kg of nab-paclitaxel. This combinatory regimen significantly reduced or eliminated preexisting lymphatic and distant metastases in MDA-MB-231 and MDA-MB-435 models. The mechanism involves paclitaxel-induced NF-κB pathway that upregulates VEGF-A and other tumor prosurvival proteins.

CONCLUSIONS

Bevacizumab prevents tumor recurrence and metastasis promoted by nab-paclitaxel activation of NF-κB pathway. Combination therapy with high-dosed nab-paclitaxel demonstrates the potential to eradicate advanced primary tumors and preexisting metastases. These findings strongly support translating this regimen into clinics.

CXCR4 as a predictive marker for locally advanced breast cancer post-neoadjuvant therapy

BACKGROUND

CXCR4 is a G-protein coupled receptor that has been linked with metastasis in several cancers, including breast cancer. We recently demonstrated that high CXCR4 levels in primary tumors of patients with breast cancer had a prognostic significance. We hypothesize that patients whose tumors had a low CXCR4 overexpression level following neoadjuvant chemotherapy will have a lower recurrence rate than those whose tumors remained high.

METHODS

Seventeen locally advanced breast cancer (LABC) patients were accrued, and tumor specimens were obtained before and after neoadjuvant therapy. CXCR4 levels were quantified by Western blots against 1 μg of protein from HeLa cells. The primary end-point was cancer recurrence. Statistical tests utilized include Kaplan-Meier survival analysis and log-rank test. A P value ≤ 0.05 was considered significant.

RESULTS

We previously defined low CXCR4 overexpression as ≤6-fold elevation and high overexpression as >6-fold elevation over HeLa cells. Of 17 LABC tumors evaluated, 10 (59%) remained in the low group, 5 (29%) reduced from high to low overexpression, and 2 (12%) maintained a high overexpression after neoadjuvant therapy. With a median follow-up of 28 mo, patients whose tumors maintained a high CXCR4 overexpression level after neoadjuvant therapy had a significantly higher rate of cancer recurrence (P = 0.0068).

CONCLUSIONS

CXCR4 was a predictive molecular marker of response to neoadjuvant chemotherapy for patients with LABC. Patients whose tumors had a persistently high CXCR4 overexpression level after neoadjuvant therapy are at a significant risk for recurrence, and therefore, should be targeted for more intensive and/or novel therapy.

Are mastectomy resection margins of clinical relevance? A systematic review

Although some guidelines support the use of post-mastectomy radiotherapy where the resection margin is involved or close, the scientific basis of this practice is not established. This systematic review explores the relationship between margin status and subsequent relapse. Pooled data from 22 studies (18,863 women) identified an involved post-mastectomy margin in 2.5%, a close margin in 8.0% and muscle or fascia invasion in 7.2% of patients. In a meta-analysis of five studies of non-inflammatory breast cancer without radiotherapy, local recurrence was increased by an involved or close margin (relative risk 2.6; P<0.00001). The effect of muscle or fascia invasion was of borderline significance (relative risk 1.7; P=0.04). In two separate meta-analyses, risk of relapse was related to margin status in women with inflammatory breast cancer (relative risk 3.1; P<0.0001) but not in those undergoing skin-sparing mastectomy (relative risk 2.1; P=0.16).