S1-Guideline: Microscopically controlled surgery.

Microscopically controlled surgery (MCS) comprises various methods allowing histologically proven complete resection of malignant tumors while at the same time sparing the tumor-free tissue in the immediate vicinity as much as possible. All procedures subsumed under MCS have in common the marking of the excised tissue for topographical orientation, which provides an assignment of remaining tumor remnants. Indications for MCS are malignant skin tumors in problem localizations as well as aggressive subtypes of skin tumors. Established indications for MCS include basal cell carcinoma, cutaneous squamous cell carcinoma, Bowen's disease as well as Bowen's carcinoma, dermatofibrosarcoma protuberans, melanoma in chronically light-damaged skin as well as acral lentiginous melanoma and Merkel cell carcinoma. For other tumors such as extramammary Paget's disease and various cutaneous sarcomas, evidence exists that MCS has demonstrated benefits, such as local recurrence rates. In addition, MCS is indicated when it is foreseeable that a complex closure technique is required and complete resection of the tumor must be assured. Various methods of MCS have been described, including 3D histology, horizontal method and Mohs surgery. A close cooperation of qualified surgeons and (dermato)pathologists as well as laboratory staff is essential for the successful application of MCS.

Effective Initial Treatment of Diffuse Pulmonary Lymphangiomatosis with Sirolimus and Propranolol: A Case Report.

Diffuse pulmonary lymphangiomatosis (DPL), an exceptionally rare disease, mainly occurs in children and young adults of both sexes. Even though DPL is considered to be a benign disease, its prognosis is relatively poor. Because of its rarity, little guidance on diagnosis and treatment is available, which makes working with patients with DPL challenging for clinicians. We present here a case of a young man with DPL in whom treatment with sirolimus and propranolol rapidly achieved positive radiological and clinical effects.

RREB1-MKL2 fusion in a spindle cell sinonasal sarcoma: biphenotypic sinonasal sarcoma or ectomesenchymal chondromyxoid tumor in an unusual site?

Biphenotypic sinonasal sarcoma (BSNS) is a rare, low grade spindle cell sarcoma, recently recognized in the WHO classification of head and neck tumors, which is characterized by a dual myogenic and neural differentiation and recurrent gene fusions, often involving PAX3-MAML3, and less commonly PAX3 fusions with other partners such as NCOA1, NCOA2, or WWTR1. Yet, in about 4% of tumors no gene rearrangements are identified. Herein, we describe a RREB1-MKL2 fusion in a BSNS lesion occurring in a 73-year-old female patient with a right maxillo-ethmoidal angle lesion. The polypoid, moderately cellular tumor with infiltrative submucosal growth was composed of fascicles of relatively bland spindle cells embedded in a loose collagenous matrix. The tumor cells showed moderate amounts of eosinophilic cytoplasm with indistinct borders and uniform, pale, ovoid to slender nuclei. The slowly proliferating neoplastic cells co-expressed smooth muscle actin and S100, and showed focal nuclear positivity for ß-catenin, while lacking staining for cytokeratins, desmin, myogenin, caldesmon, glial fibrillary acid protein, and SOX-10. Molecular analysis by targeted RNA-based next-generation sequencing identified an in-frame fusion between exon 8 of RREB1 and exon 11 of MKL2, a genetic event that was reported to be a molecular hallmark of ectomesenchymal chondromyxoid tumor. Gene rearrangements in both genes were independently verified by fluorescence in situ hybridization (FISH). To evaluate its recurrent potential an additional group of 15 fusion negative BSNS were tested for abnormalities in RREB1 and MKL2 genes by FISH, but no additional positive cases were identified.

Rationale and design of the German-speaking myeloma multicenter group (GMMG) trial HD6: a randomized phase III trial on the effect of elotuzumab in VRD induction/consolidation and lenalidomide maintenance in patients with newly diagnosed myeloma.

BACKGROUND: Despite major advances in therapy, multiple myeloma is still an incurable malignancy in the majority of patients. To increase survival, deeper remissions (i.e. CR) translating into longer PFS need to be achieved. Incorporation of new drugs (i.e. bortezomib and lenalidomide) as induction and maintenance treatment in an intensified treatment concept, including high dose melphalan (200 mg/m2), has resulted in increased CR rates, and is considered the standard of care for younger patients. Elotuzumab in combination with lenalidomide and dexamethasone has given better results as lenalidomide and dexamethasone alone in a phase III trial. The GMMG-HD6 trial will be the first phase III trial investigating the role of elotuzumab in combination with bortezomib, lenalidomide and dexamethasone (VRD) induction/consolidation and lenalidomide maintenance within a high dose concept. METHODS: GMMG-HD6 is a randomized, open, multicenter phase III trial. The planned recruitment number is 564 NDMM patients. All patients will receive 4 VRD cycles as induction and undergo peripheral blood stem cell mobilization and harvesting. Thereafter they will be treated with high dose melphalan therapy plus autologous stem cell transplantation followed by 2 cycles of VRD consolidation and lenalidomide maintenance. Patients in arm B1 + B2 will additionally receive elotuzumab in the induction phase, whereas patients in A2 + B2 will be treated with elotuzumab added to consolidation and maintenance. The primary endpoint of the trial is PFS. Secondary objectives and endpoints are OS, CR rates after induction therapy comparing the two arms VRD (A1 + A2) vs VRD + elotuzumab (B1 + B2), CR rates after consolidation treatment, best response to treatment during the study, time to progression (TTP), duration of response (DOR), toxicity and quality of life. RESULTS: Since this is the publication of a study protocol of an ongoing study, no results can be presented. DISCUSSION: This phase III trial is designed to evaluate whether the addition of elotuzumab to an intensified treatment concept with high dose melphalan chemotherapy plus autologous stem cell transplantation and induction, consolidation and maintenance treatment with bortezomib and lenalidomide is able to improve PFS compared to the same concept without elotuzumab. TRIAL REGISTRATION: NCT02495922 on June 24th, 2015.

Influence of Regioselectively Sulfated Cellulose on in Vitro Vascularization of Biomimetic Bone Matrices.

Vascularization is essential for the regeneration of bone tissue within composite material. We measured the effect of regioselectively modified cellulose/hemicellulose as an additive for porous scaffolds of collagen/hydroxyapatite nanocomposite on the tubule formation of human vascular endothelial cells. Using a coculture of endothelial cells and fibroblasts, endothelial cells formed a network of tubules within an incubation time of 14 to 24 days. A cellulose sulfate with irregular sulfation pattern along the polysaccharide backbone (13-TACS-01) led to an additional increase in vascular endothelial growth factor (VEGF)-induced tubule formation, as observed in an in vitro angiogenesis assays. In contrast with structurally different heparin, these cellulose sulfates have no apparent affinity to VEGF. Their impact on endothelial function may possibly be due to interactions with cell surface receptors/soluble factors not yet defined.

Oncogene-induced senescence: a potential breakpoint mechanism against malignant transformation in plasma cell disorders.

Oncogene-induced senescence (OIS) is a cellular tumor-suppressive mechanism present in several premalignant conditions. Here, we analyze the possible impact of OIS on malignant transformation in plasma cell disorders. Tumor samples from 125 patients with different disease stages were analyzed immunohistochemically for expression of senescence markers. Protein expression of cyclin-dependent kinase inhibitor p21Cip1/Waf1 was significantly higher in smoldering multiple myeloma (SMM) compared to monoclonal gammopathy of undetermined significance (MGUS) (p = .02) or symptomatic multiple myeloma (MM) (p = .005). SMM plasma cells expressing p21Cip1/Waf1 were negative for Ki67, consistent with senescence. While p27Kip1 was highly expressed in healthy controls, MGUS and SMM, expression decreased significantly in MM (p = .02). SMM plasma cells displayed a mutually exclusive expression of p21Cip1/Waf1/p27Kip1 suggesting compensatory mechanisms of senescence. In conclusion, we found markers of cellular senescence differentially expressed in SMM compared to MGUS and MM supporting the hypothesis of OIS as a breakpoint mechanism against malignant transformation in plasma cell disorders.

Amyloid in bone marrow smears in systemic light-chain amyloidosis.

We performed a prospective sensitivity analysis to detect amyloid in bone marrow (BM) smears stained with Congo red (CR) and according to Pappenheim of patients with systemic light-chain (AL) amyloidosis. Results were directly compared to routine BM histology and fat aspiration. We analysed 198 BM smears from patients with the diagnosis or suspicion of systemic AL amyloidosis. Ultimately, the diagnosis could be established for 168 patients. Amyloid was detected on BM smears with CR in 33% (56/168). All patients suspicious for amyloid on Pappenheim staining (n = 39) showed substantial amyloid infiltration on CR. No patient without systemic AL amyloidosis stained positive. Sensitivity for routine BM histology was 57% (74/129) and for fat aspiration 96% (134/140). Patients with amyloid on BM smears had significantly more hepatic (42 vs. 9%, p < .001), renal (78 vs. 43%, p < .001) and gastrointestinal involvement (40 vs. 22%, p < .01) and less commonly cardiac involvement (58 vs. 76%, p < .03) and consecutively no adverse prognosis. CR staining of BM smears cannot be recommended as a primary screening tool for systemic AL as its overall sensitivity is far inferior to BM histology and fat aspiration. However, we recommend using the technique when suspecting amyloid on Pappenheim staining to establish the diagnosis of systemic AL amyloidosis.

Incremental value of cardiac magnetic resonance for the evaluation of cardiac tumors in adults: experience of a high volume tertiary cardiology centre.

To assess the value of cardiac magnetic resonance imaging (CMR) in evaluating cardiac tumours in a tertiary cardiology centre. Between 2004 and 2014, 125 patients (pts.) from a total of 17000 who received a CMR examination in our institution were referred with the suspicion of cardiac tumours. A dedicated protocol was used that included standard cine SSFP acquisitions as well as tissue characterization using T1 and T2 black-blood (T1 BB and T2 BB respectively) with and without fat suppression, perfusion of the structure and late gadolinium enhancement. Patients' files were retrospectively analysed and data related to clinical status, results from other examinations (echocardiography), therapeutic approach and histology results, when performed, were collected. In 65 pts., a diagnosis of cardiac tumour was reached. 45 Pts had a biopsy. The CMR examination was concordant with the histology results in 35 (76%) pts. superior to that showed by echocardiography, 26 (58%) pts., p = 0.03. Forty-two (65%) pts. had a benign tumour and 23 (35%) a malignant process. Myxoma was the most frequent benign tumour, 27 (65%) and cardiac metastases were the most frequent form of malignancies, 21 (91%), with B cell non-Hodgkin lymphoma being the most frequent one, 4 (19%). Benign tumours were mostly located in the left atrium, 27 (64%) versus 6 (26%), p = 0.007, whereas malignant tumours had a predilection for the right atrium und left ventricle [11 (48%) vs. 3 (7%), p = 0.001 and 8 (35%) vs. 3 (7%), p = 0.03]. All benign cardiac tumours were single and did not show signs of infiltration. Conversely, malignant cardiac tumours were larger (43 ± 35 vs. 24 ± 16, p = 0.007) with a significant proportion (65%) showing myocardial infiltration. Pts with malignant cardiac tumours had a higher proportion of LGE (82 vs. 60%, p = 0.05) and exhibited more frequently an isointense signal in T1 BB images (78 vs. 61%, p = 0.04). Both groups showed similar proportion of perfusion and signal intensity in the T2 BB acquisitions (p = NS). CMR is a valuable tool in evaluating cardiac tumours, proving superior to echocardiography in establishing the type of cardiac tumour.

Targeted sequencing of refractory myeloma reveals a high incidence of mutations in CRBN and Ras pathway genes.

In this study, targeted sequencing to screen 50 multidrug refractory multiple myeloma (rMM) patients was performed by using the Multiple Myeloma Mutation Panel. Patients were pretreated with both immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs), and 88%, 78%, and 68% were refractory to an IMiD, a PI, or both, respectively. The majority of patients had progressive (82%) or refractory (78%) disease immediately before sampling, with 43% being IMiD refractory and 46% being PI refractory in the most recent line of therapy. Compared with newly diagnosed MM, an increased prevalence of mutations in the Ras pathway genes KRAS, NRAS, and/or BRAF (72%), as well as TP53 (26%), CRBN (12%), and CRBN pathway genes (10%) was observed. Longitudinal analyses performed in 3 patients with CRBN mutations at time of IMiD resistance confirmed that these mutations were undetectable at earlier, IMiD-sensitive time points. Furthermore, the functional introduction of these mutations in MM cells conferred lenalidomide resistance in vitro. These data indicate a differential genetic landscape in rMM associated with drug response.

Expression of CDKN1C in the bone marrow of patients with myelodysplastic syndrome and secondary acute myeloid leukemia is associated with poor survival after conventional chemotherapy.

We tested the hypothesis that proliferative activity of hematopoietic stem cells has impact on survival in newly diagnosed patients with myelodysplastic syndrome (MDS) and secondary acute myeloid leukemia (AML). RNA expression profiles of CD34(+) cells were analyzed in 125 MDS patients and compared to healthy controls. Prognostic impact on overall survival (OS) of mRNA proliferation signatures established for solid tumor cells was analyzed retrospectively. For validation on the protein level, immunofluorescence and immunohistochemistry analyses in bone marrow (BM) biopsies were performed, and an independent cohort of 223 MDS and secondary AML patients was investigated. Lower proliferative activity correlated with the expression of cyclin-dependent kinase inhibitor 1C (CDKN1C) and with shorter OS (p < 0.001). In multivariable analysis, higher CDKN1C expression was associated with worse OS (p = 0.02). On the BM level, a total of 84 (38%) patients showed CDKN1C protein expression before start of treatment. Patient, disease and treatment characteristics did not differ between CDKN1C-positive and -negative patients. Positive CDKN1C BM status was associated with shorter OS in multivariable analysis (HR 1.54, p = 0.04). There was an interaction between CDKN1C BM status and subsequent treatment with negative impact on OS being most pronounced in patients receiving conventional cytotoxic chemotherapy (n = 83, 2-year OS 30% versus 58%, p = 0.002). In conclusion, low-proliferative phenotype and CDKN1C expression were associated with shorter OS. CDKN1C protein expression in the BM of newly diagnosed, treatment-naïve MDS and secondary AML patients was identified as a prognostic factor for poor survival in patients treated with antiproliferative chemotherapy.

Flow cytometry-based characterization of underlying clonal B and plasma cells in patients with light chain amyloidosis.

Systemic amyloid light chain (AL) amyloidosis is a life-threatening protein deposition disorder; however, effective therapy can dramatically improve the prognosis of AL patients. Therefore, accurate diagnosis of the underlying hematologic disease is important. Multi-parameter flow cytometry (MFC) is a reliable method to analyze lymphatic neoplasias and to detect even a small lymphatic clone. We analyzed the presence of clonal plasma cell (PC) and B cells in the bone marrow of 63 patients with newly diagnosed AL amyloidosis by MFC. We compared the results with the levels of monoclonal protein, the histopathology and cytogenetic results. As reference of light chain restriction, we used the immunohistochemical results of κ or λ positive amyloid deposits in various tissues. MFC identified underlying clonal lymphatic cells in all but two patients (61 of 63, 97%). Sixty-one patients harbored malignant PCs, whereas B-cell lymphomas were identified in two patients. Furthermore, MFC indicated at least one putative immunotherapeutical target (CD20, CD38, CD52, or SLAMF7) on malignant PCs in all but one patient. These results demonstrate that MFC is a reliable tool for an accurate diagnosis of the underlying hematologic disease and the detection of potential immunotherapeutical targets in patients with AL amyloidosis.

BRAF inhibition in hairy cell leukemia with low-dose vemurafenib.

The activating mutation of the BRAF serine/threonine protein kinase (BRAF V600E) is the key driver mutation in hairy cell leukemia (HCL), suggesting opportunities for therapeutic targeting. We analyzed the course of 21 HCL patients treated with vemurafenib outside of trials with individual dosing regimens (240-1920 mg/d; median treatment duration, 90 days). Vemurafenib treatment improved blood counts in all patients, with platelets, neutrophils, and hemoglobin recovering within 28, 43, and 55 days (median), respectively. Complete remission was achieved in 40% (6/15 of evaluable patients) and median event-free survival was 17 months. Response rate and kinetics of response were independent of vemurafenib dosing. Retreatment with vemurafenib led to similar response patterns (n = 6). Pharmacodynamic analysis of BRAF V600E downstream targets showed that vemurafenib (480 mg/d) completely abrogated extracellular signal-regulated kinase phosphorylation of hairy cells in vivo. Typical side effects also occurred at low dosing regimens. We observed the development of acute myeloid lymphoma (AML) subtype M6 in 1 patient, and the course suggested disease acceleration triggered by vemurafenib. The phosphatidylinositol 3-kinase hotspot mutation (E545K) was identified in the AML clone, providing a potential novel mechanism for paradoxical BRAF activation. These data provide proof of dependence of HCL on active BRAF signaling. We provide evidence that antitumor and side effects are observed with 480 mg vemurafenib, suggesting that dosing regimens in BRAF-driven cancers could warrant reassessment in trials with implications for cost of cancer care.

Individualized medicine and demographic change as determining workload factors in pathology: quo vadis?

The advent of individualized medicine with novel guidelines, extended quality assessment as well as intensified conventional, immunohistochemical, and molecular characterization of diseases has led to a substantial increase of pathologists' workload. Furthermore, in industrialized countries, we are facing the challenges of demographic change with an aging population. This raises the question of how pathology will be affected by these developments in the future. We extracted German population data and data on the number of board-certified physicians and pathologists from official sources. These data were reviewed in the light of data on caseload, case complexity, auxiliary diagnostic procedures, and matching patient data from a large German pathology department serving as a sector independent regional service provider. The refinement of diagnostic procedures over the last decade has resulted in a 60 % increase in slide numbers per case, doubling of immunohistochemistry procedures, and more than tripling of molecular analyses. Correlation of this development to demographics suggests that an aging population will further increase the caseload and case complexity in the coming decades since patient age is tightly linked to both parameters. This development is currently not accompanied by a sufficient increase in the number of pathologists. Our data point toward an imbalance between the increase in pathology workload and the number of pathologists. Extrapolations suggest a further aggravation of this development in the future. Thus, healthcare systems need to address this problem urgently in order to cope with these challenges.

Consensus diagnostic histopathological criteria for acute gastrointestinal graft versus host disease improve interobserver reproducibility.

Graft versus host disease (GvHD) is a clinically important complication after allogeneic hematopoietic stem cell transplantation (HSCT). Its diagnosis relies on clinical and histopathological findings. In order to evaluate and improve inter-institutional diagnostic agreement on histological diagnosis and grading of acute gastrointestinal GvHD, we conducted a round robin test, which included 33 biopsies from 23 patients after HSCT. Five pathologists from different institutions independently evaluated the original sections from the biopsies submitted for diagnosis. Based on their results, consensus qualitative criteria for the assessment of typical histological features of GvHD (e.g., apoptosis, crypt destruction, mucosa denudation) were proposed, including detailed descriptions as well as histological images. In a second round robin test with involvement of the same pathologists, the reproducibility of both diagnosis and grading had improved. Remaining differences were mostly related to differential diagnostic considerations, including viral infection or toxic side effects of medication, which should be resolved by integrating histopathological findings with proper clinical information.