Significant response to apatinib monotherapy in heavily pretreated advanced HER2-positive breast cancer: a case report and literature review

The reversal of anti-HER2 resistance in advanced HER2-positive breast cancer using apatinib: two cases reports and literature review

BACKGROUND

Human epidermal growth factor receptor 2 (HER2)-targeted treatment has yielded a notable clinical benefit in patients with HER2-positive breast cancer. However, nearly 50% of patients still suffer disease progression due to resistance to HER2-targeted therapy. After the failure of macromolecular monoclonal antibodies (mAbs) therapy, we can choose small molecule tyrosine kinase inhibitors (TKIs) to reverse HER2 resistance. When small molecule TKIs resistance, we can use mAb combined with small molecule TKI, or antibody-drug conjugates (ADCs) to reverse HER2 resistance. However, then due to the availability and price of ADCs, patients may not use them. Consequently, new therapeutic approaches are required to overcome HER2-targeted therapy resistance. Vascular endothelial growth factor and its receptors (VEGF/VEGFRs) promote tumor angiogenesis. They can also activate downstream signaling pathways to promote tumorigenesis. VEGFR is a key regulator of the tyrosine kinase signaling pathway and may be a potential target in HER2-positive breast cancer. Apatinib is a small molecule TKI that specifically binds to VEGFR2 and thus exerts an antitumor effect. Although there is no definite indication for apatinib in breast cancer, it has a good benefit in advanced gastric cancer.

CASE DESCRIPTION

The two patients we reported were both HER2-positive breast cancer who we followed for more than 10 years. After the failure of multi-line anti-HER2 treatment, apatinib combined with anti-HER2 treatment had PFS of 8.4 months and 10.6 months, respectively. One patient had grade 2 hand-foot syndrome. The other had grade 2 leukopenia and grade 2 thrombocytopenia, both of them improved after control. And the best response of them were PR and SD, respectively.

CONCLUSIONS

Our cases demonstrate that, in HER2-positive breast cancer patients with HER2-targeted resistance, apatinib may be able to reverse HER2 resistance. These two cases suggest an alternative method for clinical HER2-targeted treatment of drug-resistant breast cancer patients and provide new insights for future research.

Effects of Apatinib Mesylate Monotherapy on the Incidence of Adverse Reactions and Immune Function in Patients with Breast Cancer after Radical Mastectomy

Objective

To assess the effects of monotherapy with apatinib mesylate on the incidence of adverse events and immune function in breast cancer patients after a radical mastectomy.

Methods

Between December 2018 and August 2020, 90 patients with breast cancer scheduled for a radical mastectomy in People's Liberation Army Navy 971 Hospital were randomly recruited and assigned at a ratio of 1 : 1 to receive either conventional treatment (conventional group) or apatinib mesylate after radical mastectomy (study group). The primary endpoint was disease control rate (DCR), and the secondary endpoints were adverse events and the immune function of the patients.

Results

Monotherapy with apatinib mesylate was associated with a higher DCR (86.67%) versus conventional postoperative treatment (42.23%). All patients in the study group had documented adverse events, including 2 (4.45%) cases of headache, 3 (6.67%) cases of dizziness, 9 (20.00%) cases of hypertension, 6 (13.34%) cases of hand-foot syndrome, 3 (6.67%) cases of thrombocytopenia, 1 (2.23%) case of tinnitus, 7 (15.56%) cases of fatigue, 2 (4.45%) cases of anemia, 2 (4.45%) cases of oral pain, and 10 (22.23%) cases of leukopenia. There were 23 cases of intermittent discontinuation due to adverse events during treatment, 15 cases of dose reduction, and 3 cases of discontinuation due to adverse events. The difference in preoperative and postoperative T-cell subsets and natural killer (NK) cells between the two groups did not come up to the statistical standard (P > 0.05). Monotherapy with apatinib mesylate resulted in significantly lower levels of CD4+, CD4+/CD8+, and NK cells and higher CD8+ levels versus conventional treatment at 1 week and 4 weeks postoperatively (P < 0.05).

Conclusion

Apatinib mesylate monotherapy after radical mastectomy yields a high DCR, a lower incidence of adverse events, and improved immune recovery. Clinical trials are, however, required prior to clinical promotion.

Recent advances in targeted drug delivery systems for resistant colorectal cancer

Colorectal cancer (CRC) is one of the deadliest cancers in the world, the incidences and morality rate are rising and poses an important threat to the public health. It is known that multiple drug resistance (MDR) is one of the major obstacles in CRC treatment. Tumor microenvironment plus genomic instability, tumor derived exosomes (TDE), cancer stem cells (CSCs), circulating tumor cells (CTCs), cell-free DNA (cfDNA), as well as cellular signaling pathways are important issues regarding resistance. Since non-targeted therapy causes toxicity, diverse side effects, and undesired efficacy, targeted therapy with contribution of various carriers has been developed to address the mentioned shortcomings. In this paper the underlying causes of MDR and then various targeting strategies including exosomes, liposomes, hydrogels, cell-based carriers and theranostics which are utilized to overcome therapeutic resistance will be described. We also discuss implication of emerging approaches involving single cell approaches and computer-aided drug delivery with high potential for meeting CRC medical needs.

The efficacy and safety of low-dose Apatinib in the management of stage IV luminal-type breast cancer: a case report and literature review

Advanced breast cancer (ABC) is incurable. Previous studies have shown that vascular endothelial growth factor (VEGF) inhibitors play a significant role in the angiogenesis of breast carcinoma. Apatinib, a highly selective orally administered small-molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor-2 (VEGFR2) has successfully been used as a second- and third-line agent in the management of ABC. There are also multiple reported cases where Apatinib was miraculously effective in the management of triple-negative and HER2-positive tumors. However, case reports of its effectiveness against luminal-type tumors are rare. Here, we report the case of a 34-year-old woman with hormone receptor-positive and HER2-negative ABC who was successfully treated with low-dose Apatinib. Owing to necrosis of the center of the tumor due to the effective anticancer effect of Apatinib, a large cavity formed rapidly in the primary lesion; thus, the quality of life of the patient was seriously affected. This report aims to caution physicians about this unique phenomenon when using Apatinib in clinical practice.

Continuous Low-Dose Apatinib Combined With WBRT Significantly Reduces Peritumoral Edema and Enhances the Efficacy of Symptomatic Multiple Brain Metastases in NSCLC

BACKGROUND

Symptomatic multiple brain metastases with peritumoral brain edema (PTBE) occur in non-small cell lung cancer patients (NSCLC) who are without driver mutations or are resistant to epidermal growth factor tyrosine kinase (EGFR-TKI) are often associated with an unfavorable prognosis. Whole brain radiation therapy (WBRT) which comes with many complications and unsatisfactory effects, is the only option for the treatment. Previous studies have shown that bevacizumab can reduce the volume of PTBE and improve efficiency of radiotherapy. This study evaluated the effects and safety of apatinib combined with WBRT in NSCLC patients with symptomatic multiple brain metastases and PTBE.

METHODS

We performed a retrospective review of 34 patients with symptomatic multiple brain metastases from NSCLC (number >4, and at least 1 measurable brain metastasis lesion with cerebral edema). Intracranial objective response rate (IORR), peritumoral edema and intracranial tumor volumetric measurement, Karnofsky performance status (KPS) and adverse events (AEs) were evaluated. Median intracranial progression-free survival (mIPFS) and median overall survival (mOS) were also analyzed.

RESULTS

Thirteen cases received apatinib (125 mg or 250 mg, QD, oral) combined with WBRT and 21 cases received chemotherapy combined with WBRT were inclued. Apatinib combination group can better reduce the volume of intracranial tumors and PTBE and total steroid dosage used. It was associated with a better IORR (84.6% vs 47.6%, P = 0.067), longer mIPFS (6.97 vs 4.77months; P = 0.014). There was no significant difference in mOS(7.70 vs 6.67 months; P = 0.14) between the 2 groups. The most common adverse events of apatinib combination WBRT included grade 1/2 nausea (4/13), fatigue (3/13), hypertension (2/13) and white blood cell decrease (2/13). No grade 3/4 AEs were observed.

CONCLUSION

Apatinib plus WBRT is well tolerated and may be a potential choice for relapsed or drug-resistant advanced NSCLC patients with symptomatic multiple brain metastases and PTBE.