Mechanisms of aromatase inhibitor resistance

Oestrogen receptor-positive (ER(+)) breast cancer is a major cause of cancer death in women. Although aromatase inhibitors suppress the function of ER and reduce the risk of recurrence, therapeutic resistance is common and essentially inevitable in advanced disease. This Review considers both genomic and cell biological explanations as to why ER(+) breast cancer cells persist, progress and cause an incurable, lethal, systemic disease. The design and outcomes of clinical trials are considered with the perspective that resistance mechanisms are heterogeneous, and therefore biomarker and somatic mutation-based stratification and eligibility will be essential for improvements in patient outcomes.

Expression of MAGE-A3, NY-ESO-1, LAGE-1 and PRAME in urothelial carcinoma

BACKGROUND

The potential for cancer-testis (CT) antigens as targets for immunotherapy in cancer patients has been heavily investigated, and currently cancer vaccine trials based on the CT antigens, MAGE-A3 and NY-ESO-1, are being carried out.

METHODS

We used specific q-RT-PCR assays to analyse the expression of the CT genes MAGE-A3, NY-ESO-1 (CTAG1B), LAGE-1 (CTAG2) and PRAME in a panel of bladder tumours from 350 patients with long-term follow-up and detailed treatment information.

RESULTS

Overall, 43% of the tumours expressed MAGE-A3, 35% expressed NY-ESO-1, 27% expressed LAGE-1 and 20% expressed PRAME. In all, 56% of the tumours expressed at least one of the CT genes analysed. Univariate Cox regression analysis of CT gene expression in non-muscle-invasive tumours showed that expression of MAGE-A3 (P=0.026), LAGE-1 (P=0.001) and NY-ESO-1 (P=0.040) was significantly associated with a shorter progression-free survival. In addition, we found that patients with tumours expressing PRAME responded poorly to chemotherapy (P=0.02, χ(2)-test).

CONCLUSION

Cancer-testis genes are frequently expressed in bladder cancer and especially in tumours of high stage and grade. In addition, the CT gene expression may have both prognostic and predictive value. Development of specific immunotherapy against the CT antigens in bladder cancer may ultimately increase patient survival.

Analysis of molecular intra-patient variation and delineation of a prognostic 12-gene signature in non-muscle invasive bladder cancer; technology transfer from microarrays to PCR

Background:

Multiple clinical risk factors and genetic profiles have been demonstrated to predict progression of non-muscle invasive bladder cancer; however, no easily clinical applicable gene signature has been developed to predict disease progression independent of disease stage and grade.

Methods:

We measured the intra-patient variation of an 88-gene progression signature using 39 metachronous tumours from 17 patients. For delineation of the optimal quantitative reverse transcriptase PCR panel of markers, we used 115 tumour samples from patients in Denmark, Sweden, UK and Spain.

Results:

Analysis of intra-patient variation of the molecular markers showed 71% similar classification results. A final panel of 12 genes was selected, showing significant correlation with outcome. In multivariate Cox regression analysis, we found that the 12-gene signature was an independent prognostic factor (hazard ratio=7.4 (95% confidence interval: 3.4–15.9), P<0.001) when adjusting for stage, grade and treatment. Independent validation of the 12-gene panel and the determined cut-off values is needed and ongoing.

Conclusion:

Intra-patient marker variation in metachronous tumours is present. Therefore, to increase test sensitivity, it may be necessary to test several metachronous tumours from a patient’s disease course. A PCR-based 12-gene signature significantly predicts disease progression in patients with non-muscle invasive bladder cancer.

Global Breast Cancer Research: Moving Forward

Breast cancer is a major global health problem and major cause of mortality. Although mortality trends are declining in high-income countries, trends are increasing in low- and middle-income countries (LMICs). Addressing global breast cancer research is a challenging endeavor, as notable disparities and extremely heterogeneous realities exist in different regions across the world. Basic global cancer health care needs have been addressed by the World Health Organization's (WHO) proposed list of essential medicines and by resource-stratified guidelines for screening and treatment. However, specific strategies are needed to address disparities in access to health care, particularly access to new therapies. Discussions about global research in breast cancer should take into account the ongoing globalization of clinical trials. Collaboration fostered by well-established research organizations in North America and Europe is essential for the development of infrastructure and human resources in LMICs so that researchers in these countries can begin to address regional questions. Specific challenges that impact the future of global breast cancer research include increasing the availability of trials in LMICs, developing strategies to increase patient participation in clinical trials, and creation of clear guidelines for the development of real-world evidence-based research. The main objective of this review is to encourage the discussion of challenges in global breast cancer research with the hope that collectively we will be able to generate workable proposals to advance the field.

Determinants of COVID-19 Mortality in Patients With Cancer From a Community Oncology Practice in Brazil

PURPOSE

The COVID-19 pandemic remains a public health emergency of global concern. Determinants of mortality in the general population are now clear, but specific data on patients with cancer remain limited, particularly in Latin America.

MATERIALS AND METHODS

A longitudinal multicenter cohort study of patients with cancer and confirmed COVID-19 from Oncoclínicas community oncology practice in Brazil was conducted. The primary end point was all-cause mortality after isolation of the SARS-CoV-2 by Real-Time Polymerase Chain Reaction (RT-PCR) in patients initially diagnosed in an outpatient environment. We performed univariate and multivariable logistic regression analysis and recursive partitioning modeling to define the baseline clinical determinants of death in the overall population.

RESULTS

From March 29 to July 4, 2020, 198 patients with COVID-19 were prospectively registered in the database, of which 167 (84%) had solid tumors and 31 (16%) had hematologic malignancies. Most patients were on active systemic therapy or radiotherapy (77%), largely for advanced or metastatic disease (64%). The overall mortality rate was 16.7% (95% CI, 11.9 to 22.7). In univariate models, factors associated with death after COVID-19 diagnosis were age ≥ 60 years, current or former smoking, coexisting comorbidities, respiratory tract cancer, and management in a noncurative setting (P < .05). In multivariable logistic regression and recursive partitioning modeling, only age, smoking history, and noncurative disease setting remained significant determinants of mortality, ranging from 1% in cancer survivors under surveillance or (neo)adjuvant therapy to 60% in elderly smokers with advanced or metastatic disease.

CONCLUSION

Mortality after COVID-19 in patients with cancer is influenced by prognostic factors that also affect outcomes of the general population. Fragile patients and smokers are entitled to active preventive measures to reduce the risk of SARS-CoV-2 infection and close monitoring in the case of exposure or COVID-19-related symptoms.

Unraveling the potential clinical utility of circulating tumor DNA detection in colorectal cancer-evaluation in a nationwide Danish cohort

BACKGROUND

Increasingly, circulating tumor DNA (ctDNA) is proposed as a tool for minimal residual disease (MRD) assessment. Digital PCR (dPCR) offers low analysis costs and turnaround times of less than a day, making it ripe for clinical implementation. Here, we used tumor-informed dPCR for ctDNA detection in a large colorectal cancer (CRC) cohort to evaluate the potential for post-operative risk assessment and serial monitoring, and how the metastatic site may impact ctDNA detection. Additionally, we assessed how altering the ctDNA-calling algorithm could customize performance for different clinical settings.

PATIENTS AND METHODS

Stage II-III CRC patients (N = 851) treated with a curative intent were recruited. Based on whole-exome sequencing on matched tumor and germline DNA, a mutational target was selected for dPCR analysis. Plasma samples (8 ml) were collected within 60 days after operation and-for a patient subset (n = 246)-every 3-4 months for up to 36 months. Single-target dPCR was used for ctDNA detection.

RESULTS

Both post-operative and serial ctDNA detection were prognostic of recurrence [hazard ratio (HR) = 11.3, 95% confidence interval (CI) 7.8-16.4, P < 0.001; HR = 30.7, 95% CI 20.2-46.7, P < 0.001], with a cumulative ctDNA detection rate of 87% at the end of sample collection in recurrence patients. The ctDNA growth rate was prognostic of survival (HR = 2.6, 95% CI 1.5-4.4, P = 0.001). In recurrence patients, post-operative ctDNA detection was challenging for lung metastases (4/21 detected) and peritoneal metastases (2/10 detected). By modifying the cut-off for calling a sample ctDNA positive, we were able to adjust the sensitivity and specificity of our test for different clinical contexts.

CONCLUSIONS

The presented results from 851 stage II-III CRC patients demonstrate that our personalized dPCR approach effectively detects MRD after operation and shows promise for serial ctDNA detection for recurrence surveillance. The ability to adjust sensitivity and specificity shows exciting potential to customize the ctDNA caller for specific clinical settings.

Efficacy of Anti-HER2 Agents in Combination With Adjuvant or Neoadjuvant Chemotherapy for Early and Locally Advanced HER2-Positive Breast Cancer Patients: A Network Meta-Analysis

BACKGROUND

Several (neo)adjuvant treatments for patients with HER2-positive breast cancer have been compared in different randomized clinical trials. Since it is not feasible to conduct adequate pairwise comparative trials of all these therapeutic options, network meta-analysis offers an opportunity for more detailed inference for evidence-based therapy.

METHODS

Phase II/III randomized clinical trials comparing two or more different (neo)adjuvant treatments for HER2-positive breast cancer patients were included. Relative treatment effects were pooled in two separate network meta-analyses for overall survival (OS) and disease-free survival (DFS).

RESULTS

17 clinical trials met our eligibility criteria. Two different networks of trials were created based on the availability of the outcomes: OS network (15 trials: 37,837 patients); and DFS network (17 trials: 40,992 patients). Two studies-the ExteNET and the NeoSphere trials-were included only in this DFS network because OS data have not yet been reported. The concept of the dual anti-HER2 blockade proved to be the best option in terms of OS and DFS. Chemotherapy (CT) plus trastuzumab (T) and lapatinib (L) and CT + T + Pertuzumab (P) are probably the best treatment options in terms of OS, with 62.47% and 22.06%, respectively. In the DFS network, CT + T + Neratinib (N) was the best treatment option with 50.55%, followed by CT + T + P (26.59%) and CT + T + L (20.62%).

CONCLUSION

This network meta-analysis suggests that dual anti-HER2 blockade with trastuzumab plus either lapatinib or pertuzumab are probably the best treatment options in the (neo)adjuvant setting for HER2-positive breast cancer patients in terms of OS gain. Mature OS results are still expected for the Aphinity trial and for the sequential use of trastuzumab followed by neratinib, the treatment that showed the best performance in terms of DFS in our analysis.

Access to high-cost drugs for advanced breast cancer in Latin America, particularly trastuzumab

Provision of high-level healthcare is a challenge for all low- to middle-income countries (LMICs) since healthcare systems are heterogeneous, face many challenges such as inadequate funding, inequitable distribution of resources and services and usually are not adequately equipped to deal with a huge problem such as breast cancer. The development of anti-HER2 therapies can be considered one of the most important examples of the translation of molecular biology knowledge into clinical benefits for cancer patients. While a variety of novel therapeutic strategies are emerging, current treatment regimens remain focussed on targeted therapy with monoclonal antibodies, mainly trastuzumab, the first agent developed in this field. While these results have revolutionised the outcome of HER2+ patients in clinical trials and in high-income countries where they are widely available, results have not impacted the natural history of this aggressive disease in most of the world. Unfortunately, the availability of these drugs is far from universal in many LMICs, and in Latin America, in particular, patients with HER2+ breast cancer are treated exclusively with standard chemotherapy, a more toxic and less efficient therapy. While the complexity of the situation and the multiple factors that have an impact in this scenario are recognised, we need to map the future and develop feasible strategies to address possible solutions to the problem of drug access. A clear and unbiased diagnosis of the situation is a good starting point. Defining healthcare priorities and a clear strategy for the allocation of resources is difficult but mandatory. In this article, we will discuss current and future challenges regarding access (and lack of access) to high-cost cancer drugs in Latin America, with a focus on anti-HER2 therapies.

Overall survival and progression-free survival with endocrine therapy for hormone receptor-positive, HER2-negative advanced breast cancer: review

We reviewed randomized phase II/III trials comparing first- or second-line endocrine therapy as monotherapy or in combination with targeted therapies for treatment of postmenopausal patients with hormone receptor-positive advanced breast cancer. First-line was defined as treatment for endocrine therapy-naïve advanced breast cancer or advanced disease treated with endocrine therapy in the adjuvant/neoadjuvant setting. Second-line was defined as endocrine therapy for advanced breast cancer following disease progression on endocrine therapy for advanced disease. Publications reporting progression-free survival (PFS)/time to progression (TTP) or overall survival (OS) for FDA-approved agents anastrozole, exemestane, fulvestrant 250 mg, fulvestrant 500 mg, letrozole (0.5 and 2.5 mg), megestrol acetate, and tamoxifen as monotherapy, or in combination with everolimus, palbociclib or ribociclib, were assessed. First-line monotherapy with anastrozole, fulvestrant 500 mg or letrozole 2.5 mg significantly improved PFS/TTP versus comparator endocrine therapy; however, only fulvestrant 500 mg improved OS. For endocrine therapy in combination with targeted therapies, palbociclib plus letrozole 2.5 mg, and ribociclib plus letrozole 2.5 mg significantly improved PFS versus letrozole 2.5 mg alone first-line. For second-line monotherapies, exemestane, fulvestrant 500 mg and letrozole 2.5 mg significantly improved PFS/TTP versus comparator endocrine therapy; only fulvestrant 500 mg and letrozole 2.5 mg improved OS. For second-line combination therapies, everolimus plus exemestane, and palbociclib plus fulvestrant 500 mg, improved PFS versus endocrine therapy alone. In both first- and second-line settings, aromatase inhibitors demonstrated PFS benefits versus comparator endocrine therapy; however, fulvestrant 500 mg was the only endocrine therapy included in our review to show both PFS and OS advantages compared with other endocrine therapies. Targeted agents in combination with endocrine therapy have demonstrated PFS improvements both first- and second-line; OS data are awaited.

Current Status of Neoadjuvant Endocrine Therapy in Early Stage Breast Cancer

OPINION STATEMENT

Neoadjuvant endocrine therapy (NET) with Ki67-based response monitoring is a practical, cost-effective approach to the management of clinical stage II and III estrogen receptor-positive (ER+) breast cancer. In addition to marked improvements in rates of breast conservation, the identification of extreme responders on the basis of the preoperative endocrine prognostic index (PEPI) provides a rationale to avoid chemotherapy on the basis of highly favorable prognosis in some patients. Finally, samples accrued from patients treated with neoadjuvant therapy are providing valuable insights into the molecular basis for intrinsic resistance to endocrine therapy and promise a more rational basis and precise approach to the systemic treatment of ER+ breast cancer.

Clinical implication of low estrogen receptor (ER-low) expression in breast cancer

Breast cancer is a heterogeneous disease, and the estrogen receptor (ER) remains the most important biomarker in breast oncology. Most guidelines set a positive expression threshold of 1% staining in immunohistochemistry (IHC) to define ER positivity. However, different expression levels may be associated with diverse degrees of sensitivity to endocrine therapy as ER expression may impact breast cancer molecular biology as a continuous variable. ER-lo tumors, defined as those with 1-10% ER expression, represent a relatively small subgroup of breast cancer patients, with an estimated prevalence of 2-7%. These tumors are similar to ERneg disease in their molecular landscape, clinicopathological characteristics, prognosis, and response to therapy. Nevertheless, a proportion may retain some degree of ER signaling dependency, and the possibility of responding to some degree to endocrine therapy cannot be completely ruled out. This review article discusses the most important considerations regarding the definition of ER positivity, pathology assessment, prognosis, and therapeutic implication of ERlo breast cancer from the medical oncology perspective.

Estimation of Premature Deaths From Lack of Access to Anti-HER2 Therapy for Advanced Breast Cancer in the Brazilian Public Health System

Purpose

Patients with human epidermal growth factor receptor 2 (HER2) -positive metastatic tumors treated in the public health system in Brazil do not have access to trastuzumab. This study aimed to estimate the impact of the lack of access to anti-HER2 therapies on the mortality of these patients.

Methods

On the basis of published data, the number of patients with HER2-positive advanced breast cancer in 2016 who should receive anti-HER2 targeted therapy was estimated. Three different treatment groups were considered for this hypothetical cohort: chemotherapy alone, chemotherapy plus trastuzumab, and chemotherapy plus trastuzumab and pertuzumab. The number of patients alive after 2 years of follow-up was estimated on the basis of the efficacy results of the pivotal trials considering these interventions.

Results

It was calculated that 2,008 women will be diagnosed with advanced HER2-positive breast cancer in Brazil in 2016. It was estimated that only 808 women would be alive in 2018 if they receive only chemotherapy (which is the treatment offered by the public health system). On the other hand, the bar rises to 1,408 women alive in 2018 if they receive chemotherapy plus trastuzumab and 1,576 women alive in 2018 if they receive the gold standard of chemotherapy plus trastuzumab and pertuzumab.

Conclusion

Trastuzumab is included in the WHO’s list of essential medications, but the Brazilian public health system does not yet provide this treatment to its population with advanced disease. The introduction of trastuzumab and pertuzumab would have a positive effect, preventing premature deaths in women with metastatic HER2-positive breast cancer in Brazil.

Health-related quality of life before and during chemotherapy in patients with early-stage breast cancer

Objectives

Identify the main changes in the health-related quality of life (HRQoL) of women diagnosed with breast cancer (BC) undergoing chemotherapy.

Methods

Prospective cohort study that included 33 women diagnosed with clinical stages I–III BC and who underwent adjuvant chemotherapy. HRQoL was assessed using the EORTC QLQ-C30 and EORTC QLQ-BR23 instruments 1 week before the start of chemotherapy and during the third month of chemotherapy.

Results

There was a decline in the HRQoL scores of patients during treatment. Therefore, chemotherapy alters the patient’s perceptions of their HRQoL since there is a decrease in global health status/quality of life (QoL) and functional scales such as physical functioning, role functioning, emotional functioning, social functioning, body image, sexual function and sexual enjoyment. We also observed an increase in side effects related to the systemic therapy, fatigue, nausea and vomiting, insomnia, appetite loss and diarrhoea, despite a decrease in breast symptoms and arm symptoms.

Conclusions

HRQoL was negatively affected during chemotherapy. Even though HRQoL assessment is a useful method for optimising patients’ care, its implementation into clinical practice remains a challenge. Since side effects are very often underestimated, we consider that the evaluation of HRQoL parameters should be done for BC patients treated with chemotherapy.

Advanced Stage at Diagnosis and Worse Clinicopathologic Features in Young Women with Breast Cancer in Brazil: A Subanalysis of the AMAZONA III Study (GBECAM 0115)

PURPOSE

Breast cancer (BC) in young women is uncommon and tends to present with more aggressive characteristics. To better understand and characterize this scenario in Brazil through real-world data, we performed a subanalysis of AMAZONA III study (ClinicalTrials.gov identifier: NCT02663973).

METHODS

The AMAZONA III study (GBECAM 0115) is a prospective registry that included 2,950 women newly diagnosed with invasive BC in Brazil from January 2016 until March 2018 at 22 sites. Valid data were obtained from 2,888 patients regarding age at diagnosis and complete baseline information. To compare epidemiologic and clinicopathological features at the time of diagnosis, patients with BC were divided into two groups according to age: ≤ 40 years and > 40 years. Quantitative variables were described as means, and categorical variables were described as frequencies and percentages and compared using the Pearson’s χ² test.

RESULTS

Of 2,888 women diagnosed with BC, 486 (17%) were ≤ 40 years old. Young women had higher educational level, most were employed and a significant number were married (P < .001 for all associations). Younger patients were more symptomatic at BC diagnosis (P < .001), and they also presented more frequently with stage III, T3/T4, grade 3 tumors, HER-2–positive, luminal B, and triple-negative subtypes.

CONCLUSION

Brazilian women younger than age 40 years have unfavorable clinicopathological features of BC at diagnosis, with more aggressive subtypes and advanced stage when compared with older women. These differences are not explained by socioeconomic or ethnic imbalances. The causes of a higher prevalence of BC among young women in Brazil deserve additional investigation.

Sunitinib treatment in patients with advanced renal cell cancer: the Brazilian National Cancer Institute (INCA) experience

Purpose:

The aim of this study was to assess the impact of sunitinib treatment in a non-screened group of patients with metastatic renal cell cancer (mRCC) treated by the Brazilian Unified Health System (SUS) at a single reference institution.

Material and Methods:

Retrospective cohort study, which evaluated patients with mRCC who received sunitinib between May 2010 and December 2013.

Results:

Fifty-eight patients were eligible. Most patients were male 41 (71%), with a median age of 58 years. Nephrectomy was performed in 41 (71%) patients with a median interval of 16 months between the surgery and initiation of sunitinib. The most prevalent histological subtype was clear cell carcinoma, present in 52 (91.2%) patients. In 50 patients (86%), sunitinib was the first line of systemic treatment. The main adverse effects were fatigue (57%), hypothyroidism (43%), mucositis (33%) and diarrhea (29%). Grade 3 and 4 adverse effects were infrequent: fatigue (12%), hypertension (12%), thrombocytopenia (7%), neutropenia (5%) and hand-foot syndrome (5%). Forty percent of patients achieved a partial response and 35% stable disease, with a disease control rate of 75%. Median progression free survival was 7.6 months and median overall survival was 14.1 months.

Conclusion:

Sunitinib treatment was active in the majority of patients, especially those with low and intermediate risk by MSKCC score, with manageable toxicity. Survival rates were inferior in this non-screened population with mRCC treated in the SUS.

Highlights of the 17th St Gallen International Breast Cancer Conference 2021: customising local and systemic therapies

The 17th edition of the St Gallen International Breast Cancer Conference was held in March 2021 in an entirely virtual mode. More than 3,300 participants took part in this important bi-annual critical review of the ‘state of the art’ in the multidisciplinary care of early-stage breast cancer (BC). Seventy-four experts from all continents discussed and commented on the previously elaborated consensus questions as well as numerous interrogations on early-BC diagnosis and treatment asked by the audience. The theme of this year’s Conference was ‘Customising local and systemic therapies’. This paper summarises the results of the 2021 international panel votes as a quick news update. We discuss the most important issues on genetics, pathology, surgery, radiotherapy and systemic therapies presented and debated throughout the conference. We selected the topics based on applicability into the personalised care of BC patients and focused on questions that have a clear impact on our current clinical practice.

Multidisciplinary Approach to Neoadjuvant Endocrine Therapy in Breast Cancer: A Comprehensive Review

Breast cancer is the most common type of cancer and the leading cause of cancer-related death among women worldwide. Hormone receptor-positive (HR+) tumors represent the most common form of this disease, with more than 70% of breast cancers expressing these receptors. Response and benefit to neoadjuvant chemotherapy (NCT) varies according to HR expression, with lower responses in luminal tumors as compared with hormone receptor-negative (HR-) and human epidermal growth factor receptor 2-positive (HER2+) tumors. Neoadjuvant endocrine therapy (NET) is an option for selected patients with HR+ locally advanced breast cancer. Neoadjuvant endocrine therapy has a favorable toxicity profile, and is associated with benefits such as having low cost and being more easily available even for cancer care professionals outside major urban areas or tertiary centers. These factors are particularly relevant, as 70% of breast cancer deaths occur in women from low-income and middle-income countries. Additionally, NET is being increasingly explored, not simply to allow for less extensive surgery, but also as a scientific tool, with the use of biomarkers to predict outcomes in adjuvant trials and for the individual patient. This review details the current and most relevant evidence about NET for breast cancer as well as the future directions of this field.

Impact of the COVID-19 Pandemic on Cancer Staging: An Analysis of Patients With Breast Cancer From a Community Practice in Brazil

PURPOSE

A nationwide lockdown was enforced in Brazil starting in March 2020 because of the COVID-19 pandemic when cancer screening activities were reduced. In this study, we evaluated the impact of the COVID-19 pandemic on breast cancer (BC) diagnosis.

METHODS

We extracted data from the medical records of patients age older than 18 years who were diagnosed with BC and started treatment or follow-up in private oncology institutions in Brazil between 2018 and 2021. The primary objective was to compare the stage distribution during the COVID-19 pandemic (2020-2021) with a historical prepandemic control cohort (2018-2019). Early BC was defined as stage I-II and advanced disease as stage IV.

RESULTS

We collected data for 11,753 patients with an initial diagnosis of BC, with 6,493 patients in the pandemic (2020-2021) and 5,260 patients in the prepandemic period (2018-2019). We observed a lower prevalence of early-stage BC (63.6% v 68.4%) and a higher prevalence of advanced-stage BC (16.9 v 12.7%), after the onset of the pandemic (both P < .01). This pattern was similar for both estrogen receptor-positive/human epidermal growth factor receptor 2-negative and human epidermal growth factor receptor 2-positive tumors: significantly decreased in the early stage from 69% to 67% and 68% to 58%, respectively, and a considerable increase in advanced-stage disease from 13% to 15% and 13% to 20%, respectively. For triple-negative BC, there was a significantly higher percentage of patients with advanced-stage disease during the pandemic (17% v 11%). Overall, age 50 years or older and postmenopausal status were associated with a greater risk of advanced stage at diagnosis during the pandemic period.

CONCLUSION

We observed a substantial increase in the number of cases of advanced-stage BC in Brazil during the COVID-19 pandemic.

New Routes to Silicic Acid Containing Inorganic-Organic Hybrid Precursors and Polymers

In view of the outstanding role that silicic acids (sa.) play in inorganic materials a survey will be presented regarding the possibilities of the integration of sa. in organic matrices via chemical reactions. The objective is to combine the advantageous properties of the silicic acid with those of the organic compounds in order to generate novel materials. The reactions of silicic acids with organic molecules, as studied by 29Si NMR spectroscopy, are described using the silicic acid H8Si8O20 with a defined double four-ring structure as an example. By silylation of the hydrophilic H8Si8O20 its functional organophilic derivatives were synthesized. The s.a. derivatives with epoxy-, alkoxy-, HSi-, ketoester or unsaturated groups are capable of condensation, polymerization, complexation or additive reactions leading to reactive inorganic-organic precursors or polymers with the defined silicic acid unit. The synthesis and structure of the following s.a. containing precursors and polymers will be reported, (a) inorganic-organic polymers with a high content of silanol groups, (b) microporous polymers free of silanol groups and (c) metal (Al, Zr) alkoxide complexes attached to defined silicic acid units. The model reactions of the double four-ring silicic acid derivatives can be transferred to technical silicic acid solutions prepared from water glass. The presented reaction pathways are a basis for the preparation of a great variety of new inorganic-organic compounds with tailor-made structures and properties which can be used for highly homogeneous and stoichiometric materials.

Lack of access to CDK4/6 inhibitors for premenopausal patients with metastatic breast cancer in Brazil: estimation of the number of premature deaths

Purpose

A CDK4/6 inhibitor (CDK4/6i) combined with endocrine therapy is the standard of care for patients with hormone receptor-positive (HR+) and HER2-negative (HER2-) metastatic breast cancer (MBC). However, the incorporation of these agents into clinical practice remains challenging. This study aims to estimate the impact of the lack of access to ribociclib on mortality of premenopausal patients with MBC in Brazil.

Methods

Based on published epidemiological studies and national cancer registries, we estimated the number of premenopausal patients with potential indication of ribociclib as first-line treatment for MBC. Efficacy estimates were based on results from the Monaleesa-7 trial. Our analysis is made under the unrealistic assumption that all premenopausal MBC patients would be candidates for the treatment. To estimate the number of yearly premature deaths that could be prevented, we considered the largest absolute effect on mortality when sequentially applying the observed hazard ratio.

Results

We estimated an annual incidence of 4,294 premenopausal HR+, HER2- MBC patients in Brazil. Considering these patients, at 12, 24 and 60 months, the number of surviving subjects would be 3,504, 2,859 and 1,553 for endocrine therapy (ET) alone; and 3,717, 3,217 and 2,086 for ET plus ribociclib. The largest difference between both groups was observed at the end of the sixth year when the use of ribociclib would prevent 538 premature deaths (survival of 1,805 versus 1,267 patients by the 72nd month).

Conclusion

We estimate that lack of access to CDK4/6i for patients with HR+, HER2-, MBC will cause the premature death of a significant number of premenopausal women with MBC. The unavailability of effective therapies has measurable consequences. Progress in this area demands a concerted effort to prevent further loss of lives.