Search

The clinical impact of therapy-related acute leukemias is increasing with the extension of cancer-related survival; however, the origins remain largely unknown. Acute erythroleukemia (AEL), a rare unfavorable type of myeloid neoplasia, may also develop secondary to cytotoxic therapy. The disorder is featured by specific genetic alterations, most importantly multi-allelic mutations of the TP53 gene. While AEL might appear as a part of the therapy-related MDS/AML, spectrum information regarding the genetic complexity and progression is largely missing. We present two AEL cases arising after cytotoxic therapy and melphalan-based myeloablation/autologous peripheral stem cell transplantation due to multiple myeloma (MM). As stated, multiple pathogenic TP53 variants were present unrelated to preexisting MM, in parallel with uninvolved/wild-type hemopoiesis. Potential mechanisms of leukemic transformation are discussed, which include (1) preexisting preneoplastic hemopoietic stem cells (HSC) serving as the common origin for both MM and AEL, (2) the generation and intramedullary survival of p53-deficient post-chemotherapy HSCs, (3) reinoculation of mobilized autologous TP53 mutated HSCs, and (4) melphalan treatment-related late-onset myelodysplasia/leukemia with newly acquired TP53 mutations. [ABSTRACT FROM AUTHOR]

The co-occurrence of myasthenia gravis (MG) and paroxysmal nocturnal hemoglobinuria (PNH) is rare; only one case has been published so far. We report a 63-year-old Caucasian female patient who was diagnosed with MG at the age of 43. Thymoma was also detected, and so it was surgically resected, which resulted in reasonable disease control for nearly 20 years. Slight hemolysis began to emerge, and then myasthenia symptoms progressed, so immunosuppressive therapy was started. Due to progressive disease and respiratory failure, the patient underwent plasmapheresis, and ventilatory support was stopped. Marked hemolysis was present, and diagnostic tests confirmed PNH with type III PNH cells. Her myasthenia symptoms aggravated, mechanical ventilation had to be started again, and due to the respiratory acidosis, massive hemolysis occurred. After two plasmapheresis sessions, the patient received eculizumab at 600 mg, resulting in prompt hemolysis control. After the second dose of the treatment, the patient was extubated. Still, due to their inability to cough, she developed another respiratory failure and pneumonia–sepsis, resulting in the patient's death. This case highlights the rare association between these two serious diseases and similar immune-mediated pathophysiology mechanisms involving the complement system. [ABSTRACT FROM AUTHOR]

Background: Abortion and fetal death are common in fetuses with holoprosencephaly, so genetic examinations often have to be made in a post‐mortem setting. The efficiency of the conventional karyotyping using cultured fibroblasts in these situations is limited due to frequent culture failure. In the current study, archived cases of holoprosencephaly, where post‐mortem genetic evaluation was requested and sufficient frozen material was available, were reevaluated using the quantitative fluorescence polymerase chain reaction (QF‐PCR) technique. Methods: Testing for aneuploidies of chromosomes 13, 15, 16, 18, 21, 22, X, and Y with the QF‐PCR technique was carried out on DNA isolated from archived frozen chorionic villi in seven cases of holoprosencephaly. Results: QF‐PCR was successful in all seven cases. Two cases of trisomy 13, two cases of triploidy, and one case of trisomy 18 was found meaning a 71% diagnostic yield. The success rate of QF‐PCR (100%, 7/7) was superior compared to conventional karyotyping (43%, 3/7). Conclusions: Rapid aneuploidy testing using the QF‐PCR technique is a simple, reliable, time‐ and cost‐effective method sufficient to conclude the etiologic investigation in the majority of holoprosencephaly cases post‐mortem. [ABSTRACT FROM AUTHOR]

TP53 aberrations predict chemoresistance and represent a contraindication for the use of standard chemoimmunotherapy in chronic lymphocytic leukaemia (CLL). Recent next‐generation sequencing (NGS)‐based studies have identified frequent low‐burden TP53 mutations with variant allele frequencies below 10%, but the clinical impact of these low‐burden TP53 mutations is still a matter of debate. In this study, we aimed to scrutinise the subclonal architecture and clinical impact of TP53 mutations using a sensitive, NGS‐based mutation analysis in a 'real‐world' cohort of 901 patients with CLL. In total, 225 TP53 mutations were identified in 17.5% (158/901) of the patients; 48% of these alterations represented high‐burden mutations, while 52% were low‐burden TP53 mutations. Low‐burden mutations as sole alterations were identified in 39% (62/158) of all mutated cases with 82% (51/62) of these being represented by a single low‐burden TP53 mutation. Patients harbouring low‐burden TP53 mutations had significantly lower time to first treatment compared to patients with wild‐type TP53. Our study has expanded the knowledge on the frequency, clonal architecture, and clinical impact of low‐burden TP53 mutations. By demonstrating that patients with sole low‐burden TP53 variants represent more than one‐third of patients with TP53 mutations and have an increased risk for treatment initiation, our findings strengthen the need to redefine the threshold of TP53 variant reporting to below 10% in the routine diagnostic setting. [ABSTRACT FROM AUTHOR]

Endometrial carcinoma (ECa) is one of the most common neoplasia of the female genital tract. The phosphatase and tensin (PTEN) homolog is the most frequently mutated tumor suppressor gene in endometrial carcinoma. PTEN encodes a phosphatase, a key regulatory enzyme involved in a signal transduction pathway that regulates cell growth, migration and apoptosis. The study evaluates an association between the morphological appearance of endometrial hyperplasia and ECa, and the presence of PTEN variations, PTEN protein level and intracellular localization. A total of 67 archived formalin-fixed and paraffin-embedded human biopsy tissue specimens with normal proliferative and secretory endometrium, endometrial hyperplasia without atypia and endometrial atypical hyperplasia, endometrioid the grade G1 and G3 and serous subtype of ECa were evaluated by sequencing for the presence of mutations in coding regions of PTEN gene of endometrial epithelial cells. The PTEN gene expression and intercellular localization of PTEN protein were evaluated immunohistochemically by immunoreactive score (IRS). PTEN mutation spectrum in endometrial carcinoma was identified for Slovak population. Twenty-eight non-silent mutations were identified in PTEN, twelve of them being novel, not annotated in Catalogue of Somatic Mutations in Cancer. Higher frequency of PTEN mutations was observed in serous carcinoma compared to global average. No correlation was observed between samples IRS, PTEN cellular localization and identified mutations. PTEN sequencing can be beneficial for patients considering prognosis of disease and sensitivity to treatment. [ABSTRACT FROM AUTHOR]