Abemaciclib pharmacology and interactions in the treatment of HR+/HER2- breast cancer: a critical review

Abemaciclib (ABE) in combination with endocrine therapy represents the mainstay treatment for either endocrine-resistant metastatic or high-risk early-stage HR+/HER2- breast cancer patients. Hence, an adequate knowledge of this agent pharmacodynamic, pharmacokinetic, and of its drug-drug interactions (DDIs) is crucial for an optimal patients management. Additionally, ABE interference with food and complementary/alternative medicines should be taken into account in the clinical practice. Several online tools allow to freely check DDIs and can be easily consulted before prescribing ABE. According to one of this instruments, ABE display the lowest number of interactions among the available cyclin-dependent kinase 4/6 inhibitors. Still, clinicians should be aware that online tools cannot replace the technical datasheet of the drug as well as a comprehensive clinical assessment for each patient. Here we critically review the main pharmacological features of ABE, then focusing on its potential interactions with drugs, food, and alternative medicine, in order to provide a guide for its optimal use in the treatment of HR+/HER2- breast cancer patients.

A review and metanalysis of metronomic oral single-agent cyclophosphamide for treating advanced ovarian carcinoma in the era of precision medicine

OBJECTIVE

Oral metronomic cyclophosphamide has been used as a single agent or in combination with other drugs for several solid tumors with interesting results in disease palliation and mild to moderate toxicity, notably in patients with recurrent epithelial ovarian cancer (EOC) progressing after systemic chemotherapy. In this paper, we report a review and a metanalysis of heterogeneous data published up to date.

DATA SOURCES

The literature search was restricted to single-agent MOC. The analysis was conducted through March 2023 by consulting PubMed, Embase, Google Scholar, and The Cochrane Library databases. Research string and Medical Subject Headings included "ovarian tumor," "ovarian carcinoma," or "ovarian cancer," "fallopian tube cancer," "primary peritoneal cancer," "oral chemotherapy," and "metronomic cyclophosphamide." All articles were assessed for quality by at least two investigators independently, and a < 18 patients sample size cutoff was chosen as a lower limit with a Cohen's kappa statistical coefficient for accuracy and reliability. Metanalysis of selected papers was carried out according to a fixed model.

DATA SUMMARY

The percentage of agreement between investigators on literature study selection was very high, reaching 96.9% with a Cohen's k of 0.929. MOC pooled objective response rate (ORR) and disease control rate for recurrent or platinum-refractory ovarian cancer were 18.8% (range 4-44%) and 36.2% (range 16-58.8%), respectively. The mean progressive-free survival and overall survival were 3.16 months (range 1.9 to 5.0 months) and 8.7 months (range 8 to 13 months), respectively. The fixed model metanalysis of selected studies showed a 16% median ORR (12-20% CI, p < 0.001).

CONCLUSIONS

Single-agent oral cyclophosphamide in EOC holds promise as a treatment option, even in the era of precision medicine. Genetic factors, such as DNA repair gene polymorphisms, may influence treatment response. Combining cyclophosphamide with biological agents such as PARP inhibitors or immunotherapy agents is an area of active investigation.

A retrospective, real-life analysis of metronomic oral single-agent cyclophosphamide for the treatment of platinum-pretreated advanced ovarian carcinoma in Italy

INTRODUCTION

Metronomic oral cyclophosphamide (MOC) presents many potential advantages, such as significantly less severe side effects than standard regimens, ease of administration, and the delivery of a dose-dense but not necessarily dose-intense treatment. These observations prompted us to evaluate in a retrospective, multicenter study the efficacy and toxicity of MOC in a real-life series of pretreated cancer patients.

METHODS

The study is a multicenter, retrospective analysis of the activity of single-agent MOC in patients with recurrent or residual epithelial ovarian, fallopian tube, or primary. Eligible patients were continuously treated with MOC at 50 mg/day until progression, toxicity, or death. Overall response rate (ORR), stable disease (SD), and disease control rate (DCR) were reported.

RESULTS

The study included 62 patients. Three patients reached a complete response rate (5%), 11 had a partial response rate (18), and 15 had stabilization of disease (24) for an ORR of 23% and a DCR of 47%. Patients with low-grade indolent tumors showed an ORR and an SD rate higher than that observed in non-indolent ones (33% vs. 18% and 28% vs. 14%, respectively). Overall, progression-free survival was 3.5 months (range 1-9 months).

CONCLUSION

Single-agent MOC is active and very well tolerated in a significant fraction of patients with refractory, recurrent, or residual epithelial ovarian, fallopian tube, or primary peritoneal cancer. In the vision of a practical approach, single-agent MOC may be a useful palliative treatment option for patients with poor tolerance to high-dose regimens or widely pretreated. Further studies are needed better to characterize the role of such an approach in clinical practice.

Abemaciclib-associated Diarrhea: An Exploratory Analysis of Real-life Data

BACKGROUND/AIM

Abemaciclib is a cyclin-dependent kinase 4/6 inhibitor approved in combination with endocrine therapy for treating hormone receptor-positive and human epidermal growth factor receptor 2-negative early and advanced breast cancer patients. The safety profile of abemaciclib is characterized by frequent gastrointestinal toxicity, especially diarrhea. Therefore, we performed an exploratory analysis of clinical factors that may be potentially associated with diarrhea in patients treated with abemaciclib plus endocrine therapy.

PATIENTS AND METHODS

Factors potentially predisposing to diarrhea were selected, such as age ≥70 years, concomitant medications and diseases, diet, and use of laxatives. These variables were correlated with the onset of grade 2/3 diarrhea in a cohort of patients treated with abemaciclib from advanced breast cancer. Univariate and multivariate analysis was performed. Sensitivity and specificity were tested using the ROC curve.

RESULTS

Eighty women with advanced breast cancer were included in the study. The univariate analysis found a statistically significant correlation between grade 2/3 diarrhea and age ≥70 years, polypharmacy, and concomitant gastrointestinal diseases (p<0.05). In the multivariate analysis, the number of risk factors significantly correlated with the outcome of interest (p<0.0001). ROC analysis showed our model's 82% sensitivity and 75% specificity.

CONCLUSION

Taking into account specific pre-existing factors, it is possible to estimate the risk of diarrhea in hormone receptor-positive and human epidermal growth factor receptor 2-negative - advanced breast cancer patients, candidates for abemaciclib plus endocrine therapy. In these subjects, implementing proactive prevention and adopting a dose-escalation strategy may represent practical approaches to decrease the abemaciclib toxicity burden.

New potential therapeutic-sequence strategies of TDM1 in the revolutionary era of metastatic HER2-positive breast cancer treatment: A monocentric retrospective experience

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Background: EMILIA study showed benefits in terms of both progression free survival (PFS) and overall survival (OS) administering Ado-trastuzumab emtansine (T-DM1) vs lapatinib-capecitabine in HER2+ mBC patients (pts) treated at least with a previous trastuzumab-taxane-based therapy. However a paucity of data is available on TDM1 efficacy after dual anti HER2 blockade with pertuzumab and trastuzumab (PT). Instead TH3RESA trial revealed the positive impact on OS of T-DM1 also in heavily pre-treated (at least 2 lines of T, lapatinib and taxanes regimens) pts. We conducted a retrospective analysis reporting innovative findings on the sequence of anti-HER2 treatments and how it could be potentially optimized. Methods: Between June 15, 2014 and January 31, 2020 we identified HER2+ (IHC: 3+ or 2+/FISH amplified) mBC pts treated with T-DM1, either as second-line after progression on dual blockade PT (Cohort PT) or after ≤ 3 anti her2-combined regimens (trastuzumab o lapatinib plus chemotherapy) (Cohort T). 74 pts received T-DM1: Cohort T n = 34 (all females, median age = 52,7), Cohort PT n = 40 (39 females, 1 male, median age = 52,2). Within Cohort T: 64,7 % of pts (n = 22) received T-DM1 after 1 previous anti her2-combined regimen, 20,6 % (n = 7) and 14,7 % (n = 5) in third and fourth lines, respectively. Instead, the whole Cohort PT received second line T-DM1 after pertuzumab/trastuzumab. Results: Median progression- free survival was 10,2 in Cohort T and 3,7 months in Cohort PT. As regards the best response rate, 8,8 % (n = 3/34) and 52,5 % (n = 21/40) of pts reported a progressive disease (PD) into the Cohorts T and PT, respectively: stable disease (SD) 38,2 % (n = 13/34) versus 15 % (n = 6/40); partial response (PR) 23,5 % (n = 8/34) vs 15 % (n = 6/40); complete response (CR) 23,5 % (n = 8/34) vs 12,5 % (n = 5/40). Almost 2/3 (n = 21/34) of Cohort T and half (n = 20/40) of Cohort PT pts had a 3+ IHC status. Conclusions: Our data suggest a lower efficacy of T-DM1 after progression on dual HER2-blockade PT. After all, EMILIA trial did not robustly evaluate the role of T-DM1 in this specific subset of pts. Obviously, larger prospective studies are necessary in order to optimize the best sequence strategy in the treatment of metastatic HER2+ BC, in light of the increasingly innovative anti-HER2 agents.

The prognostic significance of combined androgen receptor, E-Cadherin, Ki67 and CK5/6 expression in patients with triple negative breast cancer

Background

Triple Negative Breast Cancer (TNBC) represents a heterogeneous group of tumors with poor prognosis owing to aggressive tumor biology and lack of targeted therapies. No clear prognostic biomarkers have been identified to date for this subgroup.

Materials and Methods

In this retrospective study we evaluated the prognostic role of 4 different molecular determinants, including androgen receptor (AR), E-cadherin (CDH1), Ki67 index, and basal cytokeratins (CKs) 5/6, in a cohort of 99 patients with TNBC. All patients received neo/adjuvant chemotherapy (mostly anthracycline/taxane-based). Immunohistochemistry (IHC) was performed in formalin-fixed paraffin-embedded primary tumor samples. CDH1 expression was considered positive as ≥ 30% of the membrane cells staining. AR positivity was defined as > 10% of positive tumor cells. High Ki67 was defined as ≥20% positive tumor cells. CK5/6 expression was judged positive if the score was ≥1.

Results

The absence of AR expression was significantly associated with highly undifferentiated tumors. Univariate analyses showed that lack of expression of CDH1, tumor size and nodal status were significantly correlated with worse RFS and OS (p< 0.05). AR expression and low Ki67 showed a trend towards better RFS and OS. Patients with absent CK5/6 expression in univariate and multivariate analyses had poorer RFS (p=0.02 and p=0.002, respectively) and OS (p=0.05 and p=0.02, respectively). Multivariate analysis showed an independent association between CDH1 expression and better RFS and OS (p< 0.05) beyond tumor size, nodal status, and grade. The Kaplan-Meier curves showed that patients with AR and CDH1 negative expression and high Ki-67 levels have a significant correlation with poor outcome.

Conclusions

Our study supports the use of IHC expression of AR, CDH1, Ki67, and CK5/6 as prognostic markers in TNBCs and suggests a link between their expression and prognosis and may help to stratify TNBC patients in different prognostic classes.

Salivary miRNA-210 involvement in medication-related osteonecrosis of the jaws

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Background: Improved survival rates from cancer have increased the need to understand the health related problems of cancer treatment. Persistent oral health related problems significantly affect patient's quality of life. Medication-related osteonecrosis of the jaws (MR-ONJ) is an oral complication of antiresorptive medications, denosumab and other medications that target angiogenesis for the management of metastatic bone cancer. The purpose of this pilot study, is to investigate, for the first time, microRNAs expression in MR-ONJ. Recent studies reported the miRNA-210 (a specific angiogenic-related miRNA) demethylation in the Osteonecrosis of the Femoral Head. We hypothesized that MiRNA-210 could also be involved in MR-ONJ development. Primary objective of the study is to investigate the role of miRNA-210 in MR-ONJ pathogenesis. Secondary objective is to investigate the feasibility of salivary miRNAs detection as potential non invasive biomarkers for MR-ONJ. Methods: A case-and-control study has been designed. Inclusion criteria are malignant tumors with ongoing treatment or previous history of anti-resorptive or anti-angiogenic medications. The predictor variable is the presence or absence of MR-ONJ. Oral examination and dental x-ray examinations suggestive of MR-ONJ will be performed. Saliva sample will be collected according to the protocol by Navazesh. The methylation status of miRNA-210 will be investigated using quantitative PCR (Q-PCR). Values will be compared between case and control group. Results: The main expected results are to enroll approximatively twenty patients in case group and sixty patients in control group within a one year recruitment period, validate that saliva is a medium for the identification of biomarkers associated with MR-ONJ and confirm the hypothesis that miRNA-210 is involved in MR-ONJ development. Conclusions: Results acquired within this project would represent a contribute to the understanding of the molecular mechanisms driving to the development of MR-ONJ lesions. MiRNA-210 demethylation could serve as a potential therapeutic target for the treatment of MR-ONJ through stimulation of angiogenesis.

Efficacy of trastuzumab in unselected patients with HER2-positive metastatic breast cancer: a retrospective analysis

AIMS AND BACKGROUND

The addition of trastuzumab to chemotherapy for HER2-positive metastatic breast cancer has significantly improved progression-free survival and overall survival, although most patients develop resistance or have a primarily resistant disease. The aim of the study was to describe the efficacy and safety of a first-line treatment in unselected metastatic HER2-positive breast cancer patients, treated according to clinical practice.

METHODS

From 2000 to 2009, we conducted a retrospective multi-institutional analysis of 182 consecutive patients with HER2-positive metastatic breast cancer who underwent first-line treatment with trastuzumab. The primary end points were progression-free survival and overall survival; the secondary end points were survival after progression in patients treated with second-line chemotherapy with or without trastuzumab and safety. A total of 172 patients were analyzed.

RESULTS

Median progression-free survival and overall survival were 1.2 (95% CI, 1.1-1.4) and 4.4 years (95% CI, 3.6-5.4), respectively. For 100 patients who received second-line chemotherapy, median survival after progression was significantly longer in those who also received trastuzumab: 2.8 (95% CI, 2.1-4.0) versus 1.2 years (95% CI, 0.6-1.9).

CONCLUSIONS

Although based on retrospective data, the study confirms the role of trastuzumab as first-line treatment in metastatic breast cancer outside of a controlled trial. Moreover, information obtained on the use of trastuzumab beyond disease progression supports its use in this setting.

Retrast: Retreatment after adjuvant trastuzumab—Our regional southern Italy experience

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Background: Trastuzumab (T) is the standard of care for pts with HER2+ve BC. Relapse after adj T remains a rare event. Since the large use of T in adj setting, becomes crucial to evaluate advantages of retreatment with T for pts who relapsed after treatment in early stage. There is still lack of clinical evidence and poor data from CT to say that there is a benefit in T re-exposure after relapse following adj T. Methods: Since Jun 2006 and Dec 2011, we reviewed pts with early BC treated with T in adj therapy, relapsed and re-treated with T in first line therapy, in 10 departments of medical oncology in Sicily. We aimed to study feasibility, responses and treatment outcome. Results: 62 pts with HER2+ve fulfilled the criteria for this analysis and 47 were evaluated. Pts had a median age of 53 ys (29-79). ER/PgR-ve cases were 16 (34 %). Ki67 was > 20% in 34 pts (74%). 31 pts (64%) had >3 nodes+ve. All the pts received adj therapy with anthra+/-taxane. 55% of pts had >2 metastatic sites. 12 (25,5%) pts were revalued for HER2: 10 pts confirmed 3+ and two pts 2+ were FISH+. Median time from diagnosis to relapse was 25 mos (7 – 36). Median time from last dose of T to relapse was 10 ms (2 – 35). 33 (70,2%) pts and 14 pts (29,8%) had early (< 12 ms) and late progression (≥ 12 ms) respectively after adj T. First line of therapy was T in combination with mono/polychemotherapy in 42 pts (89,3%) and 5 pts (10,6%) respectively. 27 pts (57,4%) had objective responses (CR 5, PR 22) and 7 pts (14,8%) stable disease. 13 pts (27,6%) had progression: all of these pts had early progressive disease after adj T, 9 pts (69,2%) had Ki67>20%, 5 pts (38,4%) were ER/PgR-ve and 8 pts (61,5%) ER/PgR+ve. Median TTP was 4 mos (range 2-7). Median TTP for early and late relapses pts were respectively 3,7 and 4,8 mos, (p = 0,4). Median OS from relapse to death was 23 mos (r 12 – 37). LVSD G1 (EF < 60-50%) was observed only in 7 pts (14%). Conclusions: Our data confirm the feasibility and safety of treatment with T after adj T therapy and is active for a disease control rate in 72,4% of cases. These results demonstrate that relapses after adj T occurred early (<12 ms) in 70% of pts. However pts with primary resistance (27,6%) should be well categorized using biomolecular markers to receive up-front drugs that overcome the resistance to T.

Appropriate management of cutaneous adverse events maximizes compliance with sorafenib treatment: a single-center experience

Aims: This report describes a positive experience of adverse event (AE) management of a multidisciplinary clinical team and 18 patients with late-stage renal cell carcinoma and hepatocellular carcinoma attending the Day Hospital Unit of the ‘Centro Catanese di Oncologia Humanitas’ (Italy) over a 2-year period. Methods: The management strategy was based on preventive measures for reducing the development of cutaneous AEs, including pain, risk of infection and patient discomfort, while avoiding the discontinuation or the reduction of the sorafenib dosage. Results: As of July 2011, eight patients were still under treatment with sorafenib; seven patients experienced cutaneous AEs and two reported severe cutaneous AEs. Conclusion: Our treatment approach seemed to reduce the incidence and/or severity of AEs, keeping patients in treatment, which is essential for good treatment outcomes.