Reduced humoral immune response after BNT162b2 coronavirus disease 2019 messenger RNA vaccination in cancer patients under antineoplastic treatment.

BACKGROUND: Cancer patients are at a higher risk of developing severe coronavirus disease 2019 (COVID-19). However, the safety and efficacy of COVID-19 vaccination in cancer patients undergoing treatment remain unclear. PATIENTS AND METHODS: In this interventional prospective multicohort study, priming and booster doses of the BNT162b2 COVID-19 vaccine were administered 21 days apart to solid tumor patients receiving chemotherapy, immunotherapy, targeted or hormonal therapy, and patients with a hematologic malignancy receiving rituximab or after allogeneic hematopoietic stem cell transplantation. Vaccine safety and efficacy (until 3 months post-booster) were assessed. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD) antibody levels were followed over time (until 28 days after the booster) and in vitro SARS-CoV-2 50% neutralization titers (NT50) toward the wild-type Wuhan strain were analyzed 28 days after the booster. RESULTS: Local and systemic adverse events (AEs) were mostly mild to moderate (only 1%-3% of patients experienced severe AEs). Local, but not systemic, AEs occurred more frequently after the booster dose. Twenty-eight days after the booster vaccination of 197 cancer patients, RBD-binding antibody titers and NT50 were lower in the chemotherapy group {234.05 IU/ml [95% confidence interval (CI) 122.10-448.66] and 24.54 (95% CI 14.50-41.52), respectively} compared with healthy individuals [1844.93 IU/ml (95% CI 1383.57-2460.14) and 122.63 (95% CI 76.85-195.67), respectively], irrespective of timing of vaccination during chemotherapy cycles. Extremely low antibody responses were seen in hematology patients receiving rituximab; only two patients had RBD-binding antibody titers necessary for 50% protection against symptomatic SARS-CoV-2 infection (<200 IU/ml) and only one had NT50 above the limit of detection. During the study period, five cancer patients tested positive for SARS-CoV-2 infection, including a case of severe COVID-19 in a patient receiving rituximab, resulting in a 2-week hospital admission. CONCLUSION: The BNT162b2 vaccine is well-tolerated in cancer patients under active treatment. However, the antibody response of immunized cancer patients was delayed and diminished, mainly in patients receiving chemotherapy or rituximab, resulting in breakthrough infections.

The exploding tumour on breast magnetic resonance imaging: an infected skin comedo.

A 61-year-old woman with a histologically proven invasive lobular carcinoma entered a clinical trial, which involved repeat magnetic resonance imaging (MRI). The protocol of the repeated MRI described a T4 breast cancer with involvement of the skin (Fig 1). There were only 17 days between the first and second MRI and during this short time it appeared that there had been rapid disease progression. On the initial MRI, a skin comedo could be seen in the left breast close to the tumour. The patient had squeezed the skin comedo, which had become infected. The second MRI captured the infected skin comedo, which had the appearance of an extensive breast cancer with skin involvement. The patient could be mismanaged if the clinician does not correlate the clinical findings with the radiological findings.

The smooth and bumpy road of trastuzumab administration: from intravenous (IV) in a hospital to subcutaneous (SC) at home.

Trastuzumab has become standard of care in the treatment of early and metastatic HER2-positive breast cancer. Initially trastuzumab could only be administered intravenously (IV), however since a few years there is also a subcutaneous (SC) formulation. The efficacy and the safety profile of both formulations is the comparable. The administration logistics however have an impact on the patients, the health care professionals (HCPs), the hospital and the government. The preference for the patients (89%) and the HCPs (77%) is in favour of the SC formulation. The patient chair time per cycle, as defined by the time between entry and exit of infusion chair, is between 53 and 122 minutes shorter for SC administration. Also, the time actively dedicated by the HCP on preparation and administration SC, is between 17 and 50 minutes shorter per cycle. These time savings may increase the capacity of an oncological day clinic and reduce waiting lists. An additional benefit is that the use of SC formulation reduces the consumables and the waste. When the SC form was given at home instead of in the hospital the safety profile remained the same, but the satisfaction rate improved further for both the patients and the HCPs. The next and final step will be potentially to invest in teaching the patients to self-administer the medication. The home administration and the education of the patients and the HCPs will have a cost price and it will be interesting to see how the hospital financial authorities and the government will deal with this situation in the time of budgetary restrictions.

Mitochondrial epileptic encephalopathy, 3-methylglutaconic aciduria and variable complex V deficiency associated with TIMM50 mutations.

Mitochondrial encephalopathies are a heterogeneous group of disorders that, usually carry grave prognosis. Recently a homozygous mutation, Gly372Ser, in the TIMM50 gene, was reported in an abstract form, in three sibs who suffered from intractable epilepsy and developmental delay accompanied by 3-methylglutaconic aciduria. We now report on four patients from two unrelated families who presented with severe intellectual disability and seizure disorder, accompanied by slightly elevated lactate level, 3-methylglutaconic aciduria and variable deficiency of mitochondrial complex V. Using exome analysis we identified two homozygous missense mutations, Arg217Trp and Thr252Met, in the TIMM50 gene. The TIMM50 protein is a subunit of TIM23 complex, the mitochondrial import machinery. It serves as the major receptor in the intermembrane space, binding to proteins which cross the mitochondrial inner membrane on their way to the matrix. The mutations, which affected evolutionary conserved residues and segregated with the disease in the families, were neither present in large cohorts of control exome analyses nor in our ethnic specific exome cohort. Given the phenotypic similarity, we conclude that missense mutations in TIMM50 are likely manifesting by severe intellectual disability and epilepsy accompanied by 3-methylglutaconic aciduria and variable mitochondrial complex V deficiency. 3-methylglutaconic aciduria is emerging as an important biomarker for mitochondrial dysfunction, in particular for mitochondrial membrane defects.

Pictilisib PI3Kinase inhibitor (a phosphatidylinositol 3-kinase [PI3K] inhibitor) plus paclitaxel for the treatment of hormone receptor-positive, HER2-negative, locally recurrent, or metastatic breast cancer: interim analysis of the multicentre, placebo-controlled, phase II randomised PEGGY study.

BACKGROUND: Approximately 40% of hormone receptor-positive, HER2-negative breast cancers (BCs) are associated with activating mutations of the phosphatidylinositol 3-kinase (PI3K) pathway. Pictilisib, a potent and highly specific class I pan-PI3K inhibitor, demonstrated preclinical activity in BC cell lines and may potentiate the effect of taxanes, benefiting patients with or without aberrant activation of the PI3K pathway. PEGGY (NCT01740336), a randomised, placebo-controlled phase II trial, examined whether pictilisib augments the anti-tumour activity of paclitaxel in patients with hormone receptor-positive, HER2-negative locally recurrent or metastatic BC (mBC). We report results from the protocol-specified interim analysis. PATIENTS AND METHODS: One hundred and eighty-three eligible patients were randomised (1:1) to receive paclitaxel (90 mg/m2 weekly for 3 weeks in every 28-day cycle) with either 260 mg pictilisib or placebo (daily on days 1-5 every week). The primary end point was progression-free survival (PFS) in the intention-to-treat (ITT) population and patients with PIK3CA-mutated tumours. Secondary end points included overall response rate (ORR), duration of response, and safety. RESULTS: In the ITT population, the median PFS was 8.2 months with pictilisib (n = 91) versus 7.8 months with placebo (n = 92) [hazard ratio (HR) for progression or death, 0.95; 95% confidence interval (CI) 0.62-1.46; P = 0.83]. In patients with PIK3CA-mutated tumours, the median PFS was 7.3 months for pictilisib (n = 32) versus 5.8 months with placebo (n = 30) (HR, 1.06; 95% CI 0.52-2.12; P = 0.88). ORR was similar between treatment arms. The safety profile of pictilisib was consistent with previous reports, with no new safety signals. Proportions of patients with grade ≥3 adverse events (AEs), serious AEs, and dose reductions/discontinuations due to AEs were higher with pictilisib. CONCLUSIONS: PEGGY did not meet its primary end point, revealing no significant benefit from adding pictilisib to paclitaxel for patients with hormone receptor-positive, HER2-negative locally recurrent or mBC. CLINICAL TRIAL NUMBER: NCT01740336.

Poor concordance between CA-125 and RECIST at the time of disease progression in patients with platinum-resistant ovarian cancer: analysis of the AURELIA trial.

BACKGROUND: Data on CA-125 as a predictor of disease progression (PD) in ovarian cancer come predominantly from patients with platinum-sensitive disease receiving chemotherapy alone. We assessed concordance between CA-125-defined and RECIST-defined PD using data from the Gynecologic Cancer InterGroup (GCIG) randomized phase III AURELIA trial in platinum-resistant ovarian cancer (PROC). PATIENTS AND METHODS: Patients with PROC were randomized to receive single-agent chemotherapy with or without bevacizumab. PD by CA-125 was defined according to GCIG criteria (except that confirmatory CA-125 measurement was not required). This exploratory analysis included patients with RECIST PD and a CA-125 reading ≤28 days before and ≤21 days after RECIST-defined PD. RESULTS: Of 218 eligible patients, only 94 (43%, 95% confidence interval 36% to 50%) had concordant RECIST and CA-125 PD status (42% in the chemotherapy-alone arm; 45% in the bevacizumab combination arm, P = 0.6). There was no evidence of CA-125-defined PD in the remaining 124 patients despite PD according to imaging. There were no significant differences in baseline characteristics between patients with PD defined by both RECIST and CA-125 and those with RECIST-only PD. CA-125 was even less sensitive in detecting PD in patients with early (<8 weeks after randomization) compared with later RECIST-defined PD (69% versus 53%, respectively, not meeting CA-125 criteria; P = 0.053). There was no significant difference in survival after PD in patients with concordant PD by RECIST and CA-125 versus those with PD only by RECIST. We validated our findings in an independent study population of PROC. CONCLUSIONS: In this platinum-resistant population, PD was typically detected earlier by imaging than by CA-125, irrespective of bevacizumab treatment. Disease status by CA-125 at the time of PD was not prognostic for overall survival. Regular radiologic assessment as well as symptom benefit assessment should be considered during PROC follow-up.

Molecular imaging as a tool to investigate heterogeneity of advanced HER2-positive breast cancer and to predict patient outcome under trastuzumab emtansine (T-DM1): the ZEPHIR trial.

BACKGROUND: Only human epidermal growth factor receptor (HER)2 status determined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) has been validated to predict efficacy of HER2-targeting antibody-drug-conjugate trastuzumab emtansine (T-DM1). We propose molecular imaging to explore intra-/interpatient heterogeneity in HER2 mapping of metastatic disease and to identify patients unlikely to benefit from T-DM1. PATIENTS AND METHODS: HER2-positive mBC patients with IHC3+ or FISH ≥ 2.2 scheduled for T-DM1 underwent a pretreatment HER2-positron emission tomography (PET)/computed tomography (CT) with (89)Zr-trastuzumab. [(18)F]2-fluoro-2-deoxy-D-glucose (FDG)-PET/CT was performed at baseline and before T-DM1 cycle 2. Patients were grouped into four HER2-PET/CT patterns according to the proportion of FDG-avid tumor load showing relevant (89)Zr-trastuzumab uptake (>blood pool activity): patterns A and B were considered positive (>50% or all of the tumor load 'positive'); patterns C and D were considered negative (>50% or all of the tumor load 'negative'). Early FDG-PET/CT was defined as nonresponding when >50% of the tumor load showed no significant reduction of FDG uptake (<15%). Negative (NPV) and positive predictive values (PPV) of HER2-PET/CT, early FDG response and their combination were assessed to predict morphological response (RECIST 1.1) after three T-DM1 cycles and time-to-treatment failure (TTF). RESULTS: In the 56 patients analyzed, 29% had negative HER2-PET/CT while intrapatient heterogeneity (patterns B and C) was found in 46% of patients. Compared with RECIST1.1, respective NPV/PPV for HER2-PET/CT were 88%/72% and 83%/96% for early FDG-PET/CT. Combining HER2-PET/CT and FDG-PET/CT accurately predicted morphological response (PPV and NPV: 100%) and discriminated patients with a median TTF of only 2.8 months [n = 12, 95% confidence interval (CI) 1.4-7.6] from those with a TTF of 15 months (n = 25, 95% CI 9.7-not calculable). CONCLUSIONS: Pretreatment imaging of HER2 targeting, combined with early metabolic response assessment holds great promise for improving the understanding of tumor heterogeneity in mBC and for selecting patients who will/will not benefit from T-DM1. CLINICALTRIALSGOV IDENTIFIER: NCT01565200.

The socio-economical impact of intravenous (IV) versus subcutaneous (SC) administration of trastuzumab: future prospectives.

Trastuzumab was the first targeted therapy for HER2 positive breast cancer. It has become the standard of care for HER2 positive metastatic breast cancer since 2000 and in the adjuvant setting since 2006. Adjuvant it is given for a year and in patients with metastatic disease until progression. The standard mode of administration is intravenous. Recently a subcutaneous form has become available. A phase III study showed that there is no difference between the intravenous and subcutaneous form in terms of safety and efficacy. The patient's preference however significantly favoured the subcutaneous form. It is estimated that the use of the SC form could contribute to a cost saving between 758 and 2576 euro per annual course. For Belgium alone this could mean an estimated saving of 1.4 to 4.6 million euros per year. The potential benefit of the SC administration for healthcare facilities could be further increased when applied in a LEAN working day-care chemotherapy unit. After reviewing the existing literature we suggest to further validate the potential financial impact of SC trastuzumab compared to the traditional IV form and to introduce a scientific proposal incorporating the benefits of this formulation in a LEAN working healthcare unit.

Tuberculous mastitis presenting as a lump: a mimicking disease in a pregnant woman case report and review of literature.

Tuberculosis (TB) of the breast is a rare entity, and can be confused with many other breast disorders, like mamma carcinoma or inflammatory breast cancer. When finding granulomatous mastitis (GM) on histology, it is important to make a differential diagnosis and seek actively for clues on the presence of tuberculosis, sarcoidosis, Wegener's granulomatosis, or idiopathic granulomatous mastitis, since treatment strategies differ and maltreatment has major implications on morbidity and mortality. An extensive clinical evaluation, laboratory work up, and imaging will lead in most cases to the right diagnosis. Anti-tuberculous therapy is the core treatment for breast TB, and surgery is indicated for extensive or persistent residual disease. Here we present a case of tuberculous mastitis and a review of literature on GM.

Current view on ductal carcinoma in situ and importance of the margin thresholds: A review.

Ductal carcinoma in situ (DCIS) is a heterogeneous group of diseases that differ in biology and clinical behaviour. Until 1980, DCIS represented less than 1% of all breast cancer cases. With the increased utilization of mammography, DCIS now accounts for 15% to 25% of newly diagnosed breast cancer cases. The Van Nuys Prognostic Index (VPNI) is a commonly used tool for ductal carcinoma in situ (DCIS) treatment approach. Patient age, tumour size, tumour margins and pathological grade are used in order to stratify patients into three groups pertaining to risk of local recurrence: low-, intermediate- and high risk. Patients in the low-risk subgroup will always be treated with excision alone, while in the highest subgroup mastectomy is the safest option. Just like invasive breast cancer (IBC) there might be a curative dilemma in the intermediate-risk group. Many trials confirm that tumour margins are the most important prognostic factor of local recurrence for DCIS patients treated with breast conserving surgery alone or with breast conserving surgery plus radiotherapy. In this article we focused specifically on the literature concerning margin thresholds.

Benchmarking and audit of breast units improves quality of care.

Quality Indicators (QIs) are measures of health care quality that make use of readily available hospital inpatient administrative data. Assessment quality of care can be performed on different levels: national, regional, on a hospital basis or on an individual basis. It can be a mandatory or voluntary system. In all cases development of an adequate database for data extraction, and feedback of the findings is of paramount importance. In the present paper we performed a Medline search on "QIs and breast cancer" and "benchmarking and breast cancer care", and we have added some data from personal experience. The current data clearly show that the use of QIs for breast cancer care, regular internal and external audit of performance of breast units, and benchmarking are effective to improve quality of care. Adherence to guidelines improves markedly (particularly regarding adjuvant treatment) and there are data emerging showing that this results in a better outcome. As quality assurance benefits patients, it will be a challenge for the medical and hospital community to develop affordable quality control systems, which are not leading to excessive workload.

Desmoplastic small round cell tumor (DSRCT) arising in the ovary: report of a case diagnosed at an early stage and review of the literature.

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a rare sarcoma tumor affecting mainly young adult males. It rarely has an ovarian involvement. CASE: A 29-year-old woman presented to her gynecologist for amenorrhoea. The laboratory results demonstrated a menopausal status and the ultrasound revealed a large mass of the right ovary. The right ovary was completely removed by laparoscopy. Pathology, cytology and immunochemistry revealed a DSRCT. In January 2009 a left salpingo-oophorectomy and a right salpingectomy were performed via laparoscopy. After 35 months from diagnosis there was no clinical evidence of disease recurrence. CONCLUSION: DSRCT is a rare ovarian tumor in adolescence with a general poor outcome. Every ovarian mass regardless of age should be approached with caution.

Novel mutations in the HPS1 gene among Puerto Rican patients.

Hermansky-Pudlak syndrome (HPS) is a disorder of oculocutaneous albinism (OCA) and platelet storage pool deficiency. Eight different disease-causing genes have been identified, whose gene products are thought to be involved in the biogenesis of lysosome-related organelles. HPS type 1 (HPS-1) is the most common HPS subtype in Puerto Rico, with a frequency of 1:1800 in the northwest of the island due to a founder mutation, i.e. a 16-bp duplication in exon 15 of the HPS1 gene (c.1472_1487dup16; p.H497QfsX90). We identified three Puerto Rican HPS-1 patients who carried compound heterozygous HPS1 mutations. One patient was heterozygous for c.937G>A, causing a missense mutation (p.G313S) at the 3 splice junction of exon 10. This mutation resulted in activation of a cryptic intronic splice site causing an aberrantly spliced HPS1 mRNA that included 144-bp of intronic sequence, producing 11 novel amino acids followed by a stop codon. The other two patients were heterozygous for the previously reported c.972delC in HPS1, resulting in a frameshift and a premature stop codon (p.M325WfsX6). These findings indicate that, among Puerto Ricans, other HPS1 mutations apart from the 16-bp duplication should be considered in the analysis of this population.

Clinical features, lectin staining, and a novel GNE frameshift mutation in hereditary inclusion body myopathy.

We present a comprehensive report of two siblings with hereditary inclusion body myopathy (HIBM). The clinical features and histological characteristics of the muscle biopsies showed the typical pattern of predominantly distal vacuolar myopathy with quadriceps sparing. This was confirmed by muscle MRI. PNA lectin staining showed an increased signal at the sarcolemma in patient muscle sections compared to control muscle, indicating reduced sialylation of glycoconjugates. Mutation analysis revealed compound heterozygous mutations in the GNE gene, encoding the key enzyme in sialic acid synthesis UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase: a missense mutation (c.2086G > A; p.V696M) previously described in HIBM patients of Indian origin, and a novel frame shift mutation (c.1295delA; p.K432RfsX17) leading to a premature stopcodon. These findings confirmed the diagnosis of HIBM on the histological, molecular and biochemical level.

Clinical and cellular characterisation of Hermansky-Pudlak syndrome type 6.

BACKGROUND: In the last decade, Hermansky-Pudlak syndrome (HPS) has arisen as an instructive disorder for cell biologists to study the biogenesis of lysosome related organelles (LROs). Of the eight human HPS subtypes, only subtypes 1 through 5 are well described. AIM: To characterise extensively the HPS-6 subtype, caused by defects in HPS6, a subunit of the biogenesis of lysosome related organelles complex-2 (BLOC-2). METHODS: Mutation analysis for the HPS6 gene was performed on DNA from our group of unclassified HPS patients. The clinical phenotype of patients with HPS6 mutations was then carefully ascertained, and their cultured dermal melanocytes were employed for cellular immunofluorescence studies. RESULTS: Molecular studies showed a variety of mutations in the single exon HPS6 gene, including frame shift, missense, and nonsense mutations as well as a approximately 20 kb deletion spanning the entire HPS6 genomic region. Cellular studies revealed that the melanogenic proteins tyrosinase and tyrosinase related protein 1 failed to be efficiently delivered to the melanosomes of HPS-6 patients, explaining their hypopigmentation. Clinical studies indicated that HPS-6 patients exhibit oculocutaneous albinism and a bleeding diathesis. Importantly, granulomatous colitis and pulmonary fibrosis, debilitating features present in HPS subtypes 1 and 4, were not detected in our HPS-6 patients. CONCLUSION: The HPS-6 subtype resembles other BLOC-2 defective subtypes (that is, HPS-3 and HPS-5) in its molecular, cellular and clinical findings. These findings are not only important for providing a prognosis to newly diagnosed HPS-6 patients, but also for further elucidation of HPS function in the biogenesis of LROs.

Cerebellar ataxia with elevated cerebrospinal free sialic acid (CAFSA).

In order to identify new metabolic abnormalities in patients with complex neurodegenerative disorders of unknown aetiology, we performed high resolution in vitro proton nuclear magnetic resonance spectroscopy on patient cerebrospinal fluid (CSF) samples. We identified five adult patients, including two sisters, with significantly elevated free sialic acid in the CSF compared to both the cohort of patients with diseases of unknown aetiology (n = 144; P < 0.001) and a control group of patients with well-defined diseases (n = 91; P < 0.001). All five patients displayed cerebellar ataxia, with peripheral neuropathy and cognitive decline or noteworthy behavioural changes. Cerebral MRI showed mild to moderate cerebellar atrophy (5/5) as well as white matter abnormalities in the cerebellum including the peridentate region (4/5), and at the periventricular level (3/5). Two-dimensional gel analyses revealed significant hyposialylation of transferrin in CSF of all patients compared to age-matched controls (P < 0.001)--a finding not present in the CSF of patients with Salla disease, the most common free sialic acid storage disorder. Free sialic acid content was normal in patients' urine and cultured fibroblasts as were plasma glycosylation patterns of transferrin. Analysis of the ganglioside profile in peripheral nerve biopsies of two out of five patients was also normal. Sequencing of four candidate genes in the free sialic acid biosynthetic pathway did not reveal any mutation. We therefore identified a new free sialic acid syndrome in which cerebellar ataxia is the leading symptom. The term CAFSA is suggested (cerebellar ataxia with free sialic acid).

Initial experience with conservative treatment in cancer patients with osteonecrosis of the jaw (ONJ) and predictors of outcome.

BACKGROUND: Overall survival (OS) and outcome of cancer patients with bisphosphonate-associated osteonecrosis of the jaw (ONJ) using conservative treatment (chlorhexidine 0.12% rinse, intermittent antibiotics, and careful sequestrectomy) are unknown. DESIGN: In all, 33 ONJ patients were studied for OS and ONJ outcome. RESULTS: Median duration of bisphosphonate treatment was 27 months (range 4-115) and was stopped in 25 (76%) patients. Nine (27%) cases presented with stage 1, 21 (64%) with stage 2, and 3 (9%) with stage 3 disease. During median follow-up of 23 months, 11 patients (33%) died (median survival 39 months), with no ONJ-related fatalities. Out of 30 assessable patients, 53% no longer had exposed bone, 37% had stable lesions, and 10% showed progressive necrosis. The hazard ratio for healing with doubling of bisphosphonate exposure was 0.419 [95% confidence interval (CI) 0.178-0.982; P = 0.045], stage 2 versus stage 1 disease 0.216 (95% CI 0.063-0.738; P = 0.015), and stage 3 versus stage 1 disease 0.084 (95% CI 0.008-0.913; P = 0.042). Cessation of bisphosphonate treatment did not influence outcome. CONCLUSIONS: Conservative treatment of ONJ leads to mucosal closure in 53% of patients. Doubling the exposure time to bisphosphonates and higher stages of ONJ significantly reduce ONJ healing rates.

Tolerance of adjuvant letrozole outside of clinical trials.

Recently aromatase inhibitors have become a standard care as an adjuvant treatment for many postmenopausal patients with hormone receptor positive early breast cancer. Adjuvant letrozole was made available either immediately postoperative, after 2-3 years of tamoxifen, or as an extended treatment after 5 years of tamoxifen. Between October 2003 and October 2005, we analyzed the subjective tolerance in 185 postoperative early breast cancer patients receiving letrozole outside of a clinical trial. The most prominent toxicity was musculoskeletal pain. In addition hot flushes, increased fatigue, nausea, vomiting, anorexia, mood disturbances, vaginal dryness, hair loss and rash were also recorded. In contrast to the prospective randomized clinical trials, a high drop-out rate of 20% was documented, mainly due to aromatase inhibitor-associated arthralgia syndrome interfering significantly with the daily life of our patients. Although adjuvant aromatase inhibitors have proven to be generally superior to tamoxifen in the adjuvant setting, it is important to focus attention on the tolerance during the adjuvant therapy and to balance this against the potential benefit in individual patients. Alternative options including switching to tamoxifen remain available.