Marie-Francoise Dehou

Chronic lymphocytic leukemia mimicking recurrent carcinoma of the breast: Case report and review of the literature

Secondary localization of chronic lymphocytic leukemia (CLL) in breast is rare, while concurrent invasive ductal carcinoma and CLL manifesting as a collision tumor in breast is extremely rare. The observation of a CLL infiltration closely associated with a distinct breast neoplasm with the absence of any other localization for the leukemia is an indisputable argument for a relationship between the two diseases. The presence of both tumors is not simply due to chance. This association (CLL and carcinoma) has also been described in other organs. Hereafter, we report a second case of an 80 year-old woman in whom a leukemic infiltrate was confined to the region immediately surrounding poorly differentiated primary breast carcinoma, and we will discuss the association between CLL and carcinoma.

A Monoclonal Antibody (HAN-PC1), Reacting with a Maturation Antigen on Plasma Cells

Abstract A monoclonal antibody (moab) which reacts with plasma cells has been produced. Bone marrow plasma cells from a patient with multiple myeloma were used for the immunization of mice. After fusion, 672 hybridoma supernatants were screened by a cell binding assay. The interesting supernatants were screened by the surface/cytoplasm fluorescence microscopy assay. From the six moab reacting with plasma cells, only one (HAN-PC1) was cell specific. The expression of HAN-PCA1 was further studied on different polymorphic cell suspensions and lymphoid tissues. By this way was seen that HAN-PC1 shows a similar reactivity pattern as OKT10. Though immune precipitation followed by SDS-PAGE showed a different M.W. for HAN-PCA1 than that of OKT10. In summary, we describe a moab strongly reacting with a novel surface antigen on plasma cells.

Unusual Nonimmunoglobulin-Containing Inclusions in a Case of Follicular Large Cell Lymphoma

Intracytoplasmic inclusion bodies were found in a case of follicular large cell lymphoma. They did not react with anti-immunoglobulin antisera and showed no enzyme reactivity. On electron microscopy the inclusions consisted of loosely packed fibrillar material not surrounded by a membrane or by rough endoplasmic reticulum. They were found only in the large lymphomatous cells. Immunocytochemistry showed a reactivity of these cells with anti-HLA-Dr and the OKT10 monoclonal antibodies. The nature of the inclusions remains unknown. They differ significantly from those described in the literature in cases of B-cell lymphoproliferative disorders.

Clinical application of targeted next-generation sequencing for colorectal cancer patients: A multicentric Belgian experience

International guidelines made RAS (KRAS and NRAS) status a prerequisite for the use of anti-EGFR agents for metastatic colorectal cancer (CRC) patients. Daily, new data emerges on the theranostic and prognostic role of molecular biomarkers; this is a strong incentive for a validated, sensitive, and broadly available molecular screening test. Next-generation sequencing (NGS) has begun to supplant other technologies for genomic profiling. We report here our 2 years of clinical practice using NGS results to guide therapeutic decisions. The Ion Torrent AmpliSeq colon/lung cancer panel, which allows mutation detection in 22 cancer-related genes, was prospectively used in clinical practice (BELAC ISO 15189 accredited method). The DNA of 741 formalin-fixed paraffin-embedded CRC tissues, including primary tumors and metastasis, was obtained from 14 different Belgian institutions and subjected to targeted NGS. Of the tumors tested, 98% (727) were successfully sequenced and 89% (650) harbored at least one mutation. KRAS, BRAF and NRAS mutations were found in 335 (46%), 78 (11%) and 32 (4%) samples, respectively. These mutation frequencies were consistent with those reported in public databases. Moreover, mutations and amplifications in potentially actionable genes were identified in 464 samples (64%), including mutations in PIK3CA (14%), ERBB2 (0.4%), AKT1 (0.6%), and MAP2K1 (0.1%), as well as amplifications of ERBB2 (0.3%) and EGFR (0.3%). The median turnaround time between reception of the sample in the laboratory and report release was 8 calendar days. Overall, the AmpliSeq colon/lung cancer panel was successfully applied in daily practice and provided reliable clinically relevant information for CRC patients.