Research autopsy programmes in oncology: shared experience from 14 centres across the world.

While there is a great clinical need to understand the biology of metastatic cancer in order to treat it more effectively, research is hampered by limited sample availability. Research autopsy programmes can crucially advance the field through synchronous, extensive, and high-volume sample collection. However, it remains an underused strategy in translational research. Via an extensive questionnaire, we collected information on the study design, enrolment strategy, study conduct, sample and data management, and challenges and opportunities of research autopsy programmes in oncology worldwide. Fourteen programmes participated in this study. Eight programmes operated 24 h/7 days, resulting in a lower median postmortem interval (time between death and start of the autopsy, 4 h) compared with those operating during working hours (9 h). Most programmes (n = 10) succeeded in collecting all samples within a median of 12 h after death. A large number of tumour sites were sampled during each autopsy (median 15.5 per patient). The median number of samples collected per patient was 58, including different processing methods for tumour samples but also non-tumour tissues and liquid biopsies. Unique biological insights derived from these samples included metastatic progression, treatment resistance, disease heterogeneity, tumour dormancy, interactions with the tumour micro-environment, and tumour representation in liquid biopsies. Tumour patient-derived xenograft (PDX) or organoid (PDO) models were additionally established, allowing for drug discovery and treatment sensitivity assays. Apart from the opportunities and achievements, we also present the challenges related with postmortem sample collections and strategies to overcome them, based on the shared experience of these 14 programmes. Through this work, we hope to increase the transparency of postmortem tissue donation, to encourage and aid the creation of new programmes, and to foster collaborations on these unique sample collections. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

[Fertility preservation in female cancer patients.] / Daganatos nobetegek termékenységének megorzése.

In Hungary, an average of 2066 women under the age of 40 are diagnosed with cancer each year according to data from the National Cancer Registry. Approximately two-thirds of these patients require gonadotoxic treatment for their disease, which could potentially reduce their chances of future conception and childbirth. Currently, there are no professional guidelines on fertility preservation in Hungary, however, it is important to inform patients about their options. In our previous paper, we presented the gonadotoxic effects of oncotherapies and the currently available fertility preservation techniques. This second paper provides current treatment methods and recommends fertility preservation techniques in different cancer types. The success of an oncofertility program relies heavily on the effective communication and collaboration between oncologists and reproductive specialists involved in fertility preservation. This paper may be the first step in elaborating a guideline towards improving access to oncofertility services and ultimately improving the quality of life for young cancer survivors in Hungary. Orv Hetil. 2023; 164(29): 1134-1145.

Covid-19 és az onkológiai beteg − a 21. századi Szkülla és Kharübdisz.

The COVID-19 pandemic has had tremendous impact worldwide but possibly no other patient subset has been impacted as much as patients with a cancer diagnosis. Significantly increased morbidity and mortality was defined amongst identifiable subsets of cancer patients, such as the elderly, patients with co-morbid illnesses and certain malignancy types and therapies. In addition, major compromises in cancer care and drastic drop-offs in cancer screening rates have led to significant further setbacks in recent advances in cancer care. Emerging information as to the benefit of COVID-19 vaccinations, including booster vaccines that can benefit even the most immune suppressed along with novel anti-COVID antibodies preemptively reduce the risk of infection. Antiviral and other therapeutics mitigating the severity of COVID-19 infections now offer major insights, new and effective options and hope for being able to optimize cancer care even in the face of the ongoing pandemic.

Circulating ACE2 activity predicts mortality and disease severity in hospitalized COVID-19 patients.

OBJECTIVES: Angiotensin-converting enzyme 2 (ACE2) represents the primary receptor for SARS-CoV-2 to enter endothelial cells. Here we investigated circulating ACE2 activity to predict the severity and mortality of COVID-19. METHODS: Serum ACE2 activity was measured in COVID-19 (110 critically ill and 66 severely ill subjects at hospital admission and 106 follow-up samples) and in 32 non-COVID-19 severe sepsis patients. Associations between ACE2, inflammation-dependent biomarkers, pre-existing comorbidities, and clinical outcomes were studied. RESULTS: Initial ACE2 activity was significantly higher in critically ill COVID-19 patients (54.4 [36.7-90.8] mU/L) than in severe COVID-19 (34.5 [25.2-48.7] mU/L; P<0.0001) and non-COVID-19 sepsis patients (40.9 [21.4-65.7] mU/L; P=0.0260) regardless of comorbidities. Circulating ACE2 activity correlated with inflammatory biomarkers and was further elevated during the hospital stay in critically ill patients. Based on ROC-curve analysis and logistic regression test, baseline ACE2 independently indicated the severity of COVID-19 with an AUC value of 0.701 (95% CI [0.621-0.781], P<0.0001). Furthermore, non-survivors showed higher serum ACE2 activity vs. survivors at hospital admission (P<0.0001). Finally, high ACE2 activity (≥45.4 mU/L) predicted a higher risk (65 vs. 37%) for 30-day mortality (Log-Rank P<0.0001). CONCLUSIONS: Serum ACE2 activity correlates with COVID-19 severity and predicts mortality.

Heterogeneity of Circulating Tumor Cell-Associated Genomic Gains in Breast Cancer and Its Association with the Host Immune Response.

Tumor cells that preferentially enter circulation include the precursors of metastatic cancer. Previously, we characterized circulating tumor cells (CTC) from patients with breast cancer and identified a signature of genomic regions with recurrent copy-number gains. Through FISH, we now show that these CTC-associated regions are detected within the matched untreated primary tumors of these patients (21% to 69%, median 55.5%, n = 19). Furthermore, they are more prevalent in the metastases of patients who died from breast cancer after multiple rounds of treatment (70% to 100%, median 93%, samples n = 41). Diversity indices revealed that higher spatial heterogeneity for these regions within primary tumors is associated with increased dissemination and metastasis. An identified subclone with multiple regions gained (MRG clone) was enriched in a posttreatment primary breast carcinoma as well as multiple metastatic tumors and local breast recurrences obtained at autopsy, indicative of a distinct early subclone with the capability to resist multiple lines of treatment and eventually cause death. In addition, multiplex immunofluorescence revealed that tumor heterogeneity is significantly associated with the degree of infiltration of B lymphocytes in triple-negative breast cancer, a subtype with a large immune component. Collectively, these data reveal the functional potential of genetic subclones that comprise heterogeneous primary breast carcinomas and are selected for in CTCs and posttreatment breast cancer metastases. In addition, they uncover a relationship between tumor heterogeneity and host immune response in the tumor microenvironment. SIGNIFICANCE: As breast cancers progress, they become more heterogeneous for multiple regions amplified in circulating tumor cells, and intratumoral spatial heterogeneity is associated with the immune landscape.

The impact of communication style on patient satisfaction.

BACKGROUND: Communication between patients and health providers influences patient satisfaction, but it is unknown whether similarity in communication styles results in higher patient satisfaction. METHODS: This study was conducted in the Smilow Cancer Hospital Breast Center. During routine follow-up visits, patients completed a Communication Styles Assessment (CSA), health survey (SF-12), Princess Margaret Hospital Satisfaction with Doctor Questionnaire, and brief demographic form. Physicians and Advanced Practice Providers were also asked to complete the CSA. Patients and providers were blinded to each other's responses. A communication styles concordance score was calculated as the Pearson correlation between 80 binary CSA items for each provider/patient pair. Factors affecting patient satisfaction scores were assessed in mixed-effects models. RESULTS: In total, 330 patients were invited to participate; of these 289 enrolled and 245 returned surveys. One hundred seventy-four completed all survey components, and 18 providers completed the CSA. Among the factors considered, physical health score (effect size = 0.0058, 95% CI 0.00051 to 0.0011, p = 0.032) and employment status (0.12, 95% CI - 0.0094 to 0.25, p = 0.069) had the greatest impact on patient satisfaction. However, patients who were not employed and less physically healthy had significantly elevated satisfaction scores when their communication style was more similar to their provider's (1.52, 95% CI 0.66 to 2.38, p = 0.0016). CONCLUSIONS: Patients who were physically healthy and employed were generally more satisfied with their care. The similarity in communication styles of patients and providers had a greater impact on patient satisfaction for patients who were less physically healthy and not employed.

Tumor-Infiltrating Lymphocytes and PD-L1 Expression in Pre- and Posttreatment Breast Cancers in the SWOG S0800 Phase II Neoadjuvant Chemotherapy Trial.

Our aim was to examine the association of pretreatment tumor-infiltrating lymphocyte (TIL) count and PD-L1 levels with pathologic complete response (pCR) and assess immune marker changes following treatment in tumor specimens from the S0800 clinical trial, which randomized patients to bevacizumab + nab-paclitaxel, followed by doxorubicin/cyclophosphamide (AC) versus two control arms without bevacizumab (varying sequence of AC and nab-paclitaxel). TILs were assessed in 124 pre- and 62 posttreatment tissues (including 59 pairs). PD-L1 was assessed in 120 pre- and 43 posttreatment tissues (including 39 pairs) using the 22C3 antibody. Baseline and treatment-induced immune changes were correlated with pCR and survival using estrogen receptor (ER) and treatment-adjusted logistic and Cox regressions, respectively. At baseline, the mean TIL count was 17.4% (17% had zero TILs, 9% had ≥50% TILs). Posttreatment, mean TIL count decreased to 11% (5% had no TILs, 2% had >50% TILs). In paired samples, the mean TIL change was 15% decrease. Baseline PD-L1 was detected in 43% of cases (n = 5 in tumor cells, n = 29 stroma, n = 18 tumor + stroma). Posttreatment, PD-L1 expression was not significantly lower (33%). Higher baseline TIL count and PD-L1 positivity rate were associated with higher pCR rate even after adjustment for treatment and ER status (P = 0.018). There was no association between TIL counts, PD-L1 expression, and survival due to few events. In conclusion, TIL counts, but not PD-L1 expression, decreased significantly after treatment. Continued PD-L1 expression in some residual cancers raises the possibility that adjuvant immune checkpoint inhibitor therapy could improve survival in this patient population. Mol Cancer Ther; 17(6); 1324-31. ©2018 AACR.

Comparison of Residual Risk-Based Eligibility vs Tumor Size and Nodal Status for Power Estimates in Adjuvant Trials of Breast Cancer Therapies.

IMPORTANCE: Many large adjuvant clinical trials end up underpowered because of fewer than expected events in the control arm. Ensuring a minimum number of events would result in more informative trials. OBJECTIVE: To calculate individualized residual risk estimates using residual risk prediction software and assess whether defining eligibility based on a minimum residual risk threshold could increase the reliability of clinical trial power calculations compared with eligibility criteria based on tumor size and nodal status. DESIGN, SETTING, AND PARTICIPANTS: We estimated residual risk in 443 consecutive patients with early-stage breast cancer and assessed clinical trial power as a function of residual risk distribution among the accrued patients. We defined residual risk as the risk of recurrence that remains despite receipt of standard-of-care therapy; this risk is determined by baseline prognostic risk and by the improvement from adjuvant therapy. We performed trial simulations to examine how the power of a 2-arm, 1:1 randomized clinical trial would change as the residual risk distribution of the trial population that met eligibility criteria based on tumor size and nodal status changes. We also simulated trials that use a minimum residual risk value as eligibility criterion. MAIN OUTCOMES AND MEASURES: Residual risk; clinical trial power as a function of residual risk distribution among the patients. RESULTS: In the 443 patients (mean [SD] age, 56.1 [12.3] years; range, 23-89 years), baseline prognostic and residual risks differed substantially: 328 (74%) patients had more than 20% baseline risk of recurrence; however, after adjustment for treatment effect only 12 (27%) had more than 20% residual risk. We assessed residual risk distribution in patient cohorts that met tumor size- and nodal status-based eligibility criteria for 3 currently accruing randomized adjuvant trials; the median residual risks were 28% (interquartile range [IQR], 25%-31%), 22% (IQR, 15%-28%), and 22% (IQR, 15%-28%), respectively, indicating that the power of these trials could vary unpredictably. Simulations showed that trials that use anatomical risk-based eligibility criteria can become underpowered if they accrue patients with low residual risk despite all participants meeting eligibility requirements. Using a minimum required residual risk threshold as eligibility criterion produced more reliable power calculations. CONCLUSIONS AND RELEVANCE: When tumor size and nodal status are used to determine trial eligibility, the residual risk of recurrence can vary broadly, leading to unstable power estimates. The success of future adjuvant trials could be improved by defining patient eligibility based on a minimal residual risk of recurrence, and these trials can achieve a prespecified power with smaller sample sizes.

Erratum: Phylogenetic analysis of metastatic progression in breast cancer using somatic mutations and copy number aberrations.

This corrects the article DOI: 10.1038/ncomms14944.

Phylogenetic analysis of metastatic progression in breast cancer using somatic mutations and copy number aberrations.

Several studies using genome-wide molecular techniques have reported various degrees of genetic heterogeneity between primary tumours and their distant metastases. However, it has been difficult to discern patterns of dissemination owing to the limited number of patients and available metastases. Here, we use phylogenetic techniques on data generated using whole-exome sequencing and copy number profiling of primary and multiple-matched metastatic tumours from ten autopsied patients to infer the evolutionary history of breast cancer progression. We observed two modes of disease progression. In some patients, all distant metastases cluster on a branch separate from their primary lesion. Clonal frequency analyses of somatic mutations show that the metastases have a monoclonal origin and descend from a common 'metastatic precursor'. Alternatively, multiple metastatic lesions are seeded from different clones present within the primary tumour. We further show that a metastasis can be horizontally cross-seeded. These findings provide insights into breast cancer dissemination.

New Therapeutic Strategies for Triple-Negative Breast Cancer.

Relatively few clinically important therapeutic advances have occurred in the treatment of triple-negative breast cancer (TNBC) since the introduction of taxanes as adjuvant therapy over 20 years ago. However, this is rapidly changing due to a variety of conceptually important clinical trials and emerging new options such as immune checkpoint inhibitors and antibody-drug conjugates. Evidence also increasingly supports that platinum drugs and inhibitors of poly (ADP-ribose) polymerase, or PARP, are particularly effective in the treatment of germline BRCA-mutant cancers, including TNBC. An important development in early-stage TNBC was the recognition that extensive residual cancer after neoadjuvant chemotherapy identifies patients who remain at high risk for recurrence. This has led to the design of two ongoing adjuvant trials (one testing pembrolizumab, the other investigating platinum drugs and capecitabine) that offer a "second chance" to improve the survival of patients with residual cancer after neoadjuvant chemotherapy. Genomic analysis of TNBC has revealed large-scale transcriptional, mutational, and copy number heterogeneity, without any frequently recurrent mutations, other than TP53. Consistent with this molecular heterogeneity, most targeted agents, so far, have demonstrated low overall activity in unselected TNBC, but important "basket" trials are ongoing.

Breast carcinoma subtypes show different patterns of metastatic behavior.

The aim of our retrospective study was to analyze patterns of subtype specific metastatic spread and to identify the time course of distant metastases. A consecutive series of 490 patients with breast cancer who underwent surgery and postoperative treatment at Semmelweis University, Hungary, and diagnosed between the years 2000 and 2007 was identified from the archives of the 2nd Department of Pathology, Hungary. Molecular subtypes were defined based on the 2011 St. Gallen recommendations. Statistical analysis was performed with SPSS Statistics for Windows, Version 22.0. Distant metastasis free survival (DMFS) was defined as the time elapsed between the first pathological diagnosis of the tumor and the first distant metastasis detection. Distant metastases were detected in 124 patients. Mean time to develop metastasis was 29 months (range 0-127 months). The longest DMFS was observed in the Luminal A (LUMA) subtype (mean 39 months) whereas the shortest was seen in the HER2-positive (HER2+) subtype (mean 21 months; p = 0.012). We confirmed that HER2+ tumors carry a higher risk for distant metastases (42.1%). LUMA-associated metastases were found to be solitary in 59% of cases, whereas HER2+ tumors showed multiple metastases in 79.2% of cases. LUMA tumors showed a preference for bone-only metastasis as compared with HER2+ and triple negative breast cancer (TNBC) cases, which exhibited a higher rate of brain metastasis. The most frequent second metastatic sites of hormone receptor (HR) positive tumors were the lung and liver, whereas the brain was the most affected organ in HR-negative (HR-) cases. Tumor subtypes differ in DMFS and in pattern of distant metastases. HER2+ tumors featured the most aggressive clinical course. Further identification of subtype-specific factors influencing prognosis might have an impact on clinical care and decision-making.

Deciphering and Targeting Oncogenic Mutations and Pathways in Breast Cancer.

UNLABELLED: : Advances in DNA and RNA sequencing revealed substantially greater genomic complexity in breast cancer than simple models of a few driver mutations would suggest. Only very few, recurrent mutations or copy-number variations in cancer-causing genes have been identified. The two most common alterations in breast cancer are TP53 (affecting the majority of triple-negative breast cancers) and PIK3CA (affecting almost half of estrogen receptor-positive cancers) mutations, followed by a long tail of individually rare mutations affecting <1%-20% of cases. Each cancer harbors from a few dozen to a few hundred potentially high-functional impact somatic variants, along with a much larger number of potentially high-functional impact germline variants. It is likely that it is the combined effect of all genomic variations that drives the clinical behavior of a given cancer. Furthermore, entirely new classes of oncogenic events are being discovered in the noncoding areas of the genome and in noncoding RNA species driven by errors in RNA editing. In light of this complexity, it is not unexpected that, with the exception of HER2 amplification, no robust molecular predictors of benefit from targeted therapies have been identified. In this review, we summarize the current genomic portrait of breast cancer, focusing on genetic aberrations that are actively being targeted with investigational drugs. IMPLICATIONS FOR PRACTICE: Next-generation sequencing is now widely available in the clinic, but interpretation of the results is challenging, and its impact on treatment selection is often limited. This work provides an overview of frequently encountered molecular abnormalities in breast cancer and discusses their potential therapeutic implications. This review emphasizes the importance of administering investigational targeted therapies, or off-label use of approved targeted drugs, in the context of a formal clinical trial or registry programs to facilitate learning about the clinical utility of tumor target profiling.

Comparison of Predictive Immunohistochemical Marker Expression of Primary Breast Cancer and Paired Distant Metastasis using Surgical Material: A Practice-Based Study.

Parallel studies of primary breast carcinomas and corresponding distant metastases samples reveal considerable differences. Our aim was to highlight this issue from another perspective and provide further data based on 98 patient samples: 69 primary breast carcinoma and 85 distant metastases from bone, central nervous system (CNS) and lung (56 paired). Two independent series of immunohistochemical reactions with different antibodies for estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (Her2), along with HER2 fluroscence in situ hybridization (FISH) were performed on tissue microarrays to classify breast carcinoma and distant metastases samples into Luminal A, Luminal B-proliferating, Luminal B-HER2+, HER2+ and triple negative (TNBC) surrogate breast cancer groups. Correlation and agreement between the two assessments of ER and PgR were fair-to-moderate, and almost perfect for HER2 and Ki67. There was 40% discordance concerning immunophenotype between breast carcinomas and distant metastases. Most common metastatic site of ER+ breast carcinoma was the skeletal system (59.2%), whereas that of TNBCs was the CNS (58.8%) and lungs (23.5%). Distant metastases in bones were mostly luminal (54.3%), in the CNS, Luminal B (53.2%), and in the lung, TNBC (37.5%). The change of drugable properties of primary breast cancers in the respective bone and CNS metastases suggests that characterization of the metastasis is necessary for appropriate treatment planning.

[Immunotherapy opportunities in breast cancer]. / Új immunterápiás lehetõségek az emlõrák kezelésében.

The prognostic value of tumor infiltrating lymphocytes in breast cancer has long been recognized by histopathologists. These observations were reaffirmed by recent immunohistochemistry and gene expression profiling studies that also revealed an association between greater chemotherapy sensitivity and extensive lymphocytic infiltration in early stage breast cancers treated with neoadjuvant chemotherapy. These results suggest that local anti-tumor immune response can at least partially control cancer growth and may mediate the antitumor effects of chemotherapy. However, until recently, there was no direct clinical evidence to demonstrate that enhancing anti-tumor immune response could lead to clinical benefit in breast cancer patients. The recent development of clinically effective immune checkpoint inhibitors made it possible to test the therapeutic impact of augmenting the local anti-tumor immune response. Two Phase I clinical trials using single agent anti-PD-1 (MK-3475, pembrolizumab) and anti-PD-L1 (MPDL3280A, atezolizumab) antibodies demonstrated close to 20% tumor response rates in heavily pretreated, metastatic, triple negative breast cancers. The most remarkable feature of the responses was their long duration. Several patients had disease control close to a year, or longer, which has not previously been seen with chemotherapy regimens in this patient population. A large number of clinical trials are currently underway with these and similar drugs in the neoadjuvant, adjuvant and metastatic settings to define the role of this new treatment modality in breast cancer.

AXL-associated tumor inflammation as a poor prognostic signature in chemotherapy-treated triple-negative breast cancer patients.

A subgroup of triple-negative breast cancer (TNBC) shows epithelial-to-mesenchymal transition (EMT) features, which are sustained by the interaction between cancer cells and tumor-associated macrophages (TAMs). In this study, the clinical relevance of 30 EMT-related kinases and the potential cross-talk with TAMs were investigated in a cohort of 203 TNBC patients treated with adjuvant chemotherapy. The prognostic value of the evaluated markers was validated in two independent cohorts of TNBC patients treated with adjuvant chemotherapy (N=95; N=137). In vitro, we investigated the potential synergism between cancer cells and TAMs. We found that the EMT-related kinase AXL showed the highest correlation with the frequency of CD163-positive macrophages (rS=0.503; P<0.0001). Relapsing TNBC patients presented high expression of AXL (P<0.0001) and CD163 (P<0.018), but only AXL retained independent prognostic significance in multivariate analysis (relapse-free survival, P=0.002; overall survival P=0.001). In vitro analysis demonstrated that AXL-expressing TNBC cells were able to polarize human macrophages towards an M2-like phenotype, and modulate a specific pattern of pro-tumor cytokines and chemokines. Selective AXL inhibition impaired the activity of M2-like macrophages, reducing cancer cell invasiveness, and restoring the sensitivity of breast cancer cells to chemotherapeutic drugs. These data suggest that the EMT-related kinase AXL overexpressed in cancer cells has prognostic significance, and contributes to the functional skewing of macrophage functions in TNBC. AXL inhibition may represent a novel strategy to target cancer cells, as well as tumor-promoting TAMs in TNBC.

[Clinico-pathologically focused breast cancer research]. / Klinikopatológiai szemléletû emlõrákkutatások.

In the second half of the 20th century research focusing to breast carcinomas at the Semmelweis University had been mostly linked to the 2nd Department of Pathology. Nowadays, following the rapidly improving treatment modalities in breast cancer there is an increasing need for defining new predictive and prognostic markers. The modern molecular pathological approach helps tremendously in mapping the biological behavior of individual cases of breast cancers and meanwhile, it is one of the prerequisites of a more efficient treatment both in neoadjuvant and adjuvant settings, as well as in metastatic disease. We provide a brief review of the relevant results we have obtained in breast cancer research between 2000 and 2015.

[Autoimmune haemolytic anaemia: a review and report of four cases]. / Az autoimmun haemolyticus anaemiáról négy eset kapcsán.

Treatment of autoimmune haemolytic anaemia is still a challenge to clinicians. Even today it may be lethal. Half of the cases are secondary due to an underlying disease, and the others are primary or idiopathic cases. According to the specificity and type of autoantibodies there are warm and cold type forms of autoimmune haemolytic anaemia. The hallmark of the diagnosis is to detect the presence of haemolysis by clinical and laboratory signs and detect the underlying autoantibodies. Treatment of autoimmune haemolytic anaemia is still a challenge to clinicians. We still loose patients due to excessive haemolysis or severe infections caused by immunosuppression. First line treatment is corticosteroids. Other immunosuppressive agents like: cyclophosphamide, azathioprine, cyclosporine or the off label rituximab can be used in case of corticosteroid refractoriness. Splenectomy is a considerable option in selective cases. The authors discuss treatment options and highlight difficulties by presenting 4 cases.

Breast- and salivary gland-derived adenoid cystic carcinomas: potential post-transcriptional divergencies. A pilot study based on miRNA expression profiling of four cases and review of the potential relevance of the findings.

Adenoid cystic carcinoma (ACC) is a malignant tumor of the salivary glands but identical tumors can also arise from the breast. Despite their similar histomorphological appearance the salivary gland- and the breast-derived forms differ in their clinical features: while ACC of the salivary glands (sACC) have an aggressive clinical course, the breast-derived form (bACC) shows a very favourable clinical outcome. To date no exact molecular alterations have yet been identified which would explain the diverse clinical features of the ACCs of different origin. In our pilot experiment we investigated the post-transcriptional features of ACC cases by performing microRNA-profiling on 2-2 bACC and sACC tissues and on 1-1 normal breast and salivary gland tissue. By comparing the microRNA-profiles of the investigated samples we identified microRNAs which were expressed differently in bACC and sACC cases according to their normal controls: 7 microRNAs were overexpressed in sACC cases and downexpressed in bACC tumors (let-7b, let-7c, miR-17, miR-20a, miR-24, miR-195, miR-768-3) while 9 microRNAs were downexpressed in sACC cases and overexpressed in bACC tissues (let-7e, miR-23b, miR-27b, miR-193b, miR-320a, miR-320c, miR-768-5p, miR-1280 and miR-1826) relative to their controls. We also identified 8 microRNAs which were only expressed in sACCs and one microRNA (miR-1234) which was only absent in sACC cases. By target predictor online databases potential targets of the these microRNAs were detected to identify genes that may play central role in the diverse clinical outcome of bACC and sACC cases.