Nab-paclitaxel weekly versus dose-dense solvent-based paclitaxel followed by dose-dense epirubicin plus cyclophosphamide in high-risk HR+/HER2- early breast cancer: results from the neoadjuvant part of the WSG-ADAPT-HR+/HER2- trial.

BACKGROUND: In high-risk hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC), nanoparticle albumin-bound (nab)-paclitaxel showed promising efficacy versus solvent-based (sb)-paclitaxel in neoadjuvant trials; however, optimal patient and therapy selection remains a topic of ongoing research. Here, we investigate the potential of Oncotype DX® recurrence score (RS) and endocrine therapy (ET) response (low post-endocrine Ki67) for therapy selection. PATIENTS AND METHODS: Within the WSG-ADAPT trial (NCT01779206), high-risk HR+/HER2- EBC patients were randomized to (neo)adjuvant 4× sb-paclitaxel 175 mg/m2 q2w or 8× nab-paclitaxel 125 mg/m2 q1w, followed by 4× epirubicin + cyclophosphamide (90 mg + 600 mg) q2w; inclusion criteria: (i) cN0-1, RS 12-25, and post-ET Ki67 >10%; (ii) cN0-1 with RS >25. Patients with cN2-3 or (G3, baseline Ki67 ≥40%, and tumor size >1 cm) were allowed to be included without RS and/or ET response testing. Associations of key factors with pathological complete response (pCR) (primary) and survival (secondary) endpoints were analyzed using statistical mediation and moderation models. RESULTS: Eight hundred and sixty-four patients received neoadjuvant nab-paclitaxel (n= 437) or sb-paclitaxel (n = 427); nab-paclitaxel was superior for pCR (20.8% versus 12.9%, P = 0.002). pCR was higher for RS >25 versus RS ≤25 (16.0% versus 8.4%, P = 0.021) and for ET non-response versus ET response (15.1% versus 6.0%, P = 0.027); no factors were predictive for the relative efficacy of nab-paclitaxel versus sb-paclitaxel. Patients with pCR had longer distant disease-free survival [dDFS; hazard ratio 0.42, 95% confidence interval (CI) 0.20-0.91, P = 0.024]. Despite favorable prognostic association of RS >25 versus RS ≤25 with pCR (odds ratio 3.11, 95% CI 1.71-5.63, P ≤ 0.001), higher RS was unfavorably associated with dDFS (hazard ratio 1.03, 95% CI 1.01-1.05, P = 0.010). CONCLUSIONS: In high-risk HR+/HER2- EBC, neoadjuvant nab-paclitaxel q1w appears superior to sb-paclitaxel q2w regarding pCR. Combining RS and ET response assessment appears to select patients with highest pCR rates. The disadvantage of higher RS for dDFS is reduced in patients with pCR. These are the first results from a large neoadjuvant randomized trial supporting the use of RS to help select patients for neoadjuvant chemotherapy in high-risk HR+/HER2- EBC.

Adjuvant abemaciclib combined with endocrine therapy for high-risk early breast cancer: updated efficacy and Ki-67 analysis from the monarchE study.

BACKGROUND: Adjuvant abemaciclib combined with endocrine therapy (ET) previously demonstrated clinically meaningful improvement in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS) in hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer at the second interim analysis, however follow-up was limited. Here, we present results of the prespecified primary outcome analysis and an additional follow-up analysis. PATIENTS AND METHODS: This global, phase III, open-label trial randomized (1 : 1) 5637 patients to adjuvant ET for ≥5 years ± abemaciclib for 2 years. Cohort 1 enrolled patients with ≥4 positive axillary lymph nodes (ALNs), or 1-3 positive ALNs and either grade 3 disease or tumor ≥5 cm. Cohort 2 enrolled patients with 1-3 positive ALNs and centrally determined high Ki-67 index (≥20%). The primary endpoint was IDFS in the intent-to-treat population (cohorts 1 and 2). Secondary endpoints were IDFS in patients with high Ki-67, DRFS, overall survival, and safety. RESULTS: At the primary outcome analysis, with 19 months median follow-up time, abemaciclib + ET resulted in a 29% reduction in the risk of developing an IDFS event [hazard ratio (HR) = 0.71, 95% confidence interval (CI) 0.58-0.87; nominal P = 0.0009]. At the additional follow-up analysis, with 27 months median follow-up and 90% of patients off treatment, IDFS (HR = 0.70, 95% CI 0.59-0.82; nominal P < 0.0001) and DRFS (HR = 0.69, 95% CI 0.57-0.83; nominal P < 0.0001) benefit was maintained. The absolute improvements in 3-year IDFS and DRFS rates were 5.4% and 4.2%, respectively. Whereas Ki-67 index was prognostic, abemaciclib benefit was consistent regardless of Ki-67 index. Safety data were consistent with the known abemaciclib risk profile. CONCLUSION: Abemaciclib + ET significantly improved IDFS in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer, with an acceptable safety profile. Ki-67 index was prognostic, but abemaciclib benefit was observed regardless of Ki-67 index. Overall, the robust treatment benefit of abemaciclib extended beyond the 2-year treatment period.

Co-expression of transcription factor AP-2beta (TFAP2B) and GATA3 in human mammary epithelial cells with intense, apicobasal immunoreactivity for CK8/18.

AP-2ß is a new mammary epithelial differentiation marker and its expression is preferentially retained and enhanced in lobular carcinoma in situ and invasive lobular breast cancer. In normal breast epithelium AP-2ß is expressed in a scattered subpopulation of luminal cells. So far, these cells have not been further characterized. Co-expression of AP-2ß protein and luminal epithelium markers (GATA3, CK8/18), hormone receptors [estrogen receptor (ER), androgen receptor (AR)] and candidate stem cells markers (CK5/14, CD44) were assessed by double-immunofluorescence staining in normal mammary gland epithelium. The subpopulation of AP-2ß-positive mammary epithelial cells showed an almost complete, superimposable co-expression with GATA3 and a peculiar intense, ring-like appearing immunoreactivity for CK8/18. Confocal immunofluorescence microscopy revealed an apicobasal staining for CK8/18 in AP-2ß-positive cells, which was not seen in in AP-2ß-negative cells. Furthermore, AP-2ß-positive displayed a partial co-expression with ER and AR, but lacked expression of candidate stem cell markers CK5/14 and CD44. In summary, AP-2ß is a new luminal mammary epithelial differentiation marker, which is expressed in the GATA3-positive subpopulation of luminal epithelial cells. These AP-2ß-positive/GATA3-positive cells also show a peculiar CK8/18-expression which may indicate a previously unknown functionally specialized mammary epithelial cell population.

[Bone marrow fibrosis in primary myelofibrosis in relation to myelodysplasia- and age-related mutations of hematopoietic cells]. / Knochenmarkfibrose bei primärer Myelofibrose in Abhängigkeit von myelodysplasie- und altersassoziierten Mutationen der Hämatopoese.

Besides histopathological findings, there are no indicators of increased risk for fibrotic progression in myeloproliferative neoplasms (MPNs). Age-related clonal hematopoiesis (ARCH) or clonal hematopoiesis of indetermined potential (CHIP) are frequent findings in the elderly and combinations with MPN driver mutations (JAK2, MPL, and CALR) have been described. To determine the impact of ARCH/CHIP-related mutations for the development of fibrosis in primary myelofibrosis (PMF), the mutational status of cases with fibrotic progression from grade 0 to grade 2/3 (n = 77) as evidenced by follow-up bone marrow biopsies (median 6.2 years) was compared to prefibrotic PMF samples without the development of fibrosis (n = 27; median follow-up 7.3 years). Frequent ARCH/CHIP-associated mutations (TET2, ASXL1, DNMT3A) demonstrable at presentation were not connected with fibrotic progression. However, mutations that are rarely found in ARCH/CHIP (SRSF2, U2AF1, SF3B1, IDH1/2, and EZH2) were present in 24.7% of cases with later development of fibrosis and not detectable in cases staying free from fibrosis (P = 0.0028). Determination of tumor mutational burden (TMB) in a subgroup of cases (n = 32) did not show significant differences (7.68 mutations/MB vs. 6.85 mutations/MB). We conclude that mutations rarely found in ARCH/CHIP provide an independent risk factor for rapid fibrotic progression (median 2.0 years) when already manifest at first presentation.

[Neuroendocrine differentiation in breast cancer]. / Neuroendokrine Differenzierung beim Mammakarzinom.

To classify as breast cancer with neuroendocrine differentiation a growth pattern as encountered in well differentiated (G1, G2) neuroendocrine tumors (NET) of the gastrointestinal tract and the lung must be present in addition to the immunohistochemical expression of neuroendocrine markers (chromogranin, synaptophysin). The majority of breast cancers fulfilling these criteria show hormone receptor positivity and with regard to prognosis resemble luminal type of breast cancer from which they are not fundamentally different. Despite lacking clinical relevance the up-coming WHO classification of breast cancer will nevertheless introduce the new category of NET luminal type. Immunohistochemical detection of neuroendocrine marker alone cannot be considered as sufficient for classification because it can frequently be encountered in other types of breast cancer (e.g. mucinous, solid papillary). From low grade NET with good differentiation those with poor differentiation and most frequently small cell appearance have to be differentiated. Poorly differentiated NET can primarily originate in the breast, which may be indicated by intraductal growth and co-expression of GATA3 but in these cases metastasis of extra mammary cancers has to be considered and correlation with the clinical findings is required for correct classification.

[Donor liver histology : Joint recommendations of the DGP, DTG and DSO]. / Histologische Diagnostik bei Spenderlebern : Gemeinsame Empfehlungen von DGP, DTG und DSO.

BACKGROUND: The indications, implementation and reporting of liver biopsies for deceased organ donation are not mandatory or regulated. Reliable data on outcome quality and prognostic relevance are therefore not available. Defined standards are thus required to enable meaningful studies and to ensure high data quality of a national transplantation registry. OBJECTIVE: Presentation of a synopsis of available studies and literature-based recommendations. RESULTS AND CONCLUSION: Against the background of an organ shortage and a growing number of older donors, pretransplantation liver histology is of significant relevance to guide clinical decision making. With the joint recommendations of the German Transplantation Society (DTG), the German Society of Pathology (DGP) and the German Organ Transplantation Foundation (DSO) standardized procedures are defined for the first time.

[Ki67: biological intertumor variance versus variance of assay]. / Ki67-Tumorheterogenität vs. Assayheterogenität.

Since its first description at the Institute of Pathology in Kiel more than 34 years ago, the immunohistochemical proliferation marker Ki67 has been shown to be of prognostic significance in a huge number of retrospective and even some prospective trials on malignant tumours of various tissue derivation. Lack of standardization in the evaluation provides potential sources of variance in assessment. Tumour area to be assessed, minimum number of cells to be analyzed, tedious counting cell by cell or semiquantitative eyeballing, choice of immunohistochemical techniques represent nonstandardized issues that potentially lead to considerable assay heterogeneity. In addition, interpretation is not homogeneous, in particular with regard to thresholds between high and low proliferative activity. Due to these numerous potential methodological limitations, for a long time Ki67 was not generally accepted as a prognostic marker, in particular outside Germany and by nonpathologists. However, in recent years a shift has taken place. Despite the challenge that biological heterogeneity may be hidden by differences in assay performance, Ki67 now plays an important auxiliary role in grading of malignant neoplasms such as breast cancer, neuroendocrine tumours and malignant lymphomas. In this context it is applied in clinical diagnostics as well as in clinical trials for the purpose of stratification. Because of its widespread use, it is of utmost importance to raise awareness of the potential methodological limitations in order to use Ki67 in a meaningful way.

[Ectopia of mammary tissue]. / Ektopien des Mammagewebes.

Ectopic breast tissue may represent the complete breast (accessory breast), glandular tissue without areola or nipple (aberrant breast tissue), or exclusively the nipple (polythelia). Localization is along the embryonic milk ridge extending from the axilla to the vulva. Only rarely, is ectopic tissue found outside of the milk ridge. Most frequently affected are the axilla, the breast itself, and its close neighbourhood. Ectopic breast tissue may rarely give rise to tumours such as fibroadenoma or carcinoma.

[Possibilities and limitations of molecular pathology in dermatohistology]. / Möglichkeiten und Grenzen der Molekularpathologie in der Dermatohistologie.

Malignant tumours, infections caused by microorganisms or genodermatoses are diagnosed with additional help of molecular pathology methods. Polymerase chain reaction (PCR), sequencing and in situ hybridisations play an important role. It remains to be seen if methods such as "liquid biopsies" or "single cell genomics" can be developed as routine diagnostics. High technical efforts, high costs and no possibility for resistency testing is accompanied by fast verification, high sensitivity and high specificity. Overall, molecular pathology results have to be combined with the clinical picture, histology or immunohistochemistry and culturing results to achieve a correct diagnosis for the patient.

[Clinical and pathological characteristics of intravascular lymphomas]. / Klinische und pathologische Charakteristika intravaskulärer Lymphome.

Intravascular B­cell lymphomas (IVL) are rare neoplasms that can manifest at any age (mean age ~62-63 years). About half of the cases are associated with Epstein-Barr virus. The most common sites of manifestation are the brain, skin, and bone marrow. The diagnosis is difficult due to unspecific clinical presentation and laboratory changes. FACS (fluorescence-activated cell sorting) and clonality analysis from peripheral blood and radiological findings are often not diagnostic. The most sensitive and most specific diagnostic method is the histopathological and immunohistochemical evaluation of a tissue biopsy. Because of the rarity of this disease, little is known about therapy and prognosis, whereby therapy is mainly similar to non-IVL lymphomas. The prognosis is poor; median survival after diagnosis is approximately one year.

De-escalation strategies in HER2-positive early breast cancer (EBC): final analysis of the WSG-ADAPT HER2+/HR- phase II trial: efficacy, safety, and predictive markers for 12 weeks of neoadjuvant dual blockade with trastuzumab and pertuzumab ± weekly paclitaxel.

BACKGROUND: Response rates in HER2-overexpressing EBC treated with neoadjuvant chemotherapy and trastuzumab (T) have been improved by addition of pertuzumab (P). The prospective, phase II, neoadjuvant WSG-ADAPT HER2+/HR- trial assessed whether patients with strong early response to dual blockade alone might achieve pathological complete response (pCR) comparable to that of patients receiving dual blockade and chemotherapy. PATIENTS AND METHODS: Female patients with HER2+/HR- EBC (M0) were randomized (5:2) to 12 weeks of T + P ± weekly paclitaxel (pac) at 80 mg/m2. Early response was defined as proliferation decrease ≥30% of Ki-67 (versus baseline) or low cellularity (<500 invasive tumor cells) in the 3-week biopsy. The trial was designed to test non-inferiority for pCR in early responding patients of the T + P arm versus all chemotherapy-treated patients. RESULTS: From February 2014 to December 2015, 160 patients were screened, 92 were randomized to T + P and 42 to T + P+pac. Baseline characteristics were well balanced (median age 54 versus 51.5 years, cT2 51.1 versus 52.4%, cN0 54.3 versus 61.9%); 91.3% of patients completed T + P per protocol and 92.9% T + P+pac. The pCR rate in the T + P+pac arm was 90.5%, compared with 36.3% in the T + P arm as a whole. In the T + P arm, 24/92 were classified as non-responders, and their pCR rate was only 8.3% compared with 44.7% in responders (38/92) and 42.9% in patients with unclassified early response (30/92). No new safety signals were observed in the study population. CONCLUSION: Addition of taxane monotherapy to dual HER2 blockade in a 12-week neoadjuvant setting substantially increases pCR rates in HER2+/HR- EBC compared with dual blockade alone, even within early responders to dual blockade. Early non-response under dual blockade strongly predicts failure to achieve pCR.

[Analysis of therapy-relevant receptors in bone marrow carcinosis : Comparison of pathological and clinical parameters]. / Untersuchung von therapierelevanten Rezeptoren bei Knochenmarkkarzinosen : Ein Vergleich pathologischer und klinischer Parameter.

BACKGROUND: Bone marrow carcinosis is a sign of advanced tumor stage with nonspecific clinical and hematological symptoms. Diagnosis is based on bone marrow biopsy and histopathology, but biopsies are not part of the standard work-up in oncological diseases and data on the correlation between clinical presentation and pathological findings are sparse. MATERIAL AND METHODS: In a retrospective single-center study, data from 20 tumor patients with bone marrow carcinosis were analyzed. Bone marrow biopsies were re-evaluated regarding quantity of tumor cells, fibrosis/necrosis, and bone changes. Immunohistochemistry of potential therapy-relevant receptors and PD-L1 was performed. RESULTS: The median age in these 20 patients (13 women, 7 men) was 65 years. The most frequent diagnoses were breast (n = 8) and lung cancer (n = 5). Anemia (94% of patients), thrombocytopenia (72%), and elevated LDH (83%) were frequent findings. The degree of bone marrow infiltration was highly variable and accounted for between 1 and 95% of biopsy space. Significant bone remodeling was present in 14/20 biopsies. No correlation could be found between histological and radiological findings. Treated patients showed some clinical and biochemical improvement, but the overall survival was poor (median 4.5 months, range < 0.5 to 21.5 months). DISCUSSION: Anemia and thrombocytopenia are frequently associated with bone marrow carcinosis, but are nonspecific. The extent of tumor cell infiltration and osteolytic/osteoblastic changes did not correlate with radiological findings. Therapy-relevant target factors should be evaluated, but therapeutic options are often limited and the prognosis is bad.

Quality assurance trials for Ki67 assessment in pathology.

Ki67 is a broadly used proliferation marker in surgical pathology with an obvious need for standardization to improve reproducibility of assessment. Here, we present results of the so far only existing round robin tests on Ki67, organized annually in Germany, Austria, and Switzerland from 2010 to 2015 with up to 160 participating laboratories (QuIP). In each quality assessment trial, eight probes from each breast cancer, neuroendocrine tumor, and malignant lymphoma were compiled on a tissue microarray (TMA). TMAs were stained in the participants' laboratories with antibodies and procedures also applied in their daily routine. Participating pathologists were expected to assign Ki67 values to one of four different categories for each tumor type. All local stainings and evaluations were reassessed by the organizing panel and compared to a preset standard. On average, 95% of participants reached the benchmark of over 80% concordance rates with the Ki67 category pre-established by the panel. Automatization and type of antibody did not affect the success rate. Concordance rates differed between tumor entities being highest in each tumor type with either very high or very low labeling indices. Lower rates were seen for intermediate Ki67 levels. Staining quality improved during the observation period as did inter-observer concordance with 85% of participants achieving excellent agreement (kappa > 0.8) in the first year and over 95% in 2015. In conclusion, regular external quality assurance trials have been established as a tool to improve the reproducibility and reliability of the prognostic and predictive proliferation marker Ki67.

Increased megakaryocytic proliferation, pro-platelet deposition and expression of fibrosis-associated factors in children with chronic myeloid leukaemia with bone marrow fibrosis.

Paediatric chronic myeloid leukaemia (ped-CML) is rare and ped-CML with fibre accumulation in the bone marrow (MF) is thought to be even rarer. In adults (ad-CML), fibrosis represents an adverse prognostic factor. So far, the pro-fibrotic changes in the bone marrow microenvironment have not been investigated in detail in ped-CML. From a total of 66 ped-CML in chronic phase, biopsies were analysable and 10 had MF1/2 (MF1, n=8/10; MF2, n=2/10). We randomly selected 16 ped-CML and 16 ad-CML cases with and without fibrosis (each n=8) as well as 18 non-neoplastic controls. Bone marrow samples were analysed with a real-time PCR-based assay (including 127 genes for paediatric cases) and by immunohistochemistry. We found increased expression of megakaryocytic genes in ped-CML. The number of megakaryocytes and pro-platelets are increased in CML patients, but the most significant increase was noted for ped-CML-MF1/2. Anti-fibrotic MMP9 expression was lower in children than in adults. Cell mobilisation-related CXCL12 was decreased in young and adult patients with CML but not the corresponding receptor CXCR4. In summary, fibre accumulation in ped-CML-MF1/2 is associated with increased megakaryocytic proliferation and increased interstitial pro-platelet deposition. Deregulated expression of matrix-modulating factors shifts the bone marrow microenvironment towards fibrosis.