Automated detection of residual cells after sex-mismatched stem-cell transplantation - evidence for presence of disease-marker negative residual cells

Amenorrhoea with XY karyotype postbone marrow transplant

A 17-year-old girl presented with secondary amenorrhoea. She developed normal age-appropriate secondary sexual characteristics and attained menarche at the age of 13 years. One year following her menarche, she was diagnosed with acute myeloid leukaemia and was treated with chemotherapy, total body radiation and bone marrow transplant with complete remission. The matched donor was her elder male sibling. Her evaluation for secondary amenorrhoea included full hormonal analysis and pelvic ultrasound scan. These suggested hypergonadotrophic hypogonadism with a normal uterus and ovaries. Peripheral leucocyte karyotype as part of routine hypogonadism workup was found to be 46 XY. The differential diagnosis of Swyer syndrome, which entails surgical removal of gonads due to the high risk of gonadoblastoma, was raised initially before reviewing the laboratory results of previous chromosomal analysis. Considering her medical history, the amenorrhoea was finally attributed to ovarian insufficiency due to chemotherapy and radiotherapy. The 46 XY karyotyping could be explained by the bone marrow transplant received from her donor brother. Hypogonadism causing amenorrhoea is commonly encountered after chemoradiotherapy. Pretreatment and post-treatment chromosomal analysis is essential in such cases. Karyotyping could be misleading especially if the patient suffered from graft-versus-host reaction post gender mismatched bone marrow transplant.

The current state of molecular cytogenetics in cancer diagnosis

Cytogenetics and molecular cytogenetics are and will continue to be indispensable tools in cancer diagnostics. Leukemia and lymphoma diagnostics are still emphases of routine (molecular) cytogenetics and corresponding studies of solid tumors gain more and more prominence. Here, first a historical perspective of molecular tumor cytogenetics is provided, which is followed by the basic principles of the fluorescence in situ hybridization (FISH) approach. Finally the current state of molecular cytogenetics in cancer diagnostics is discussed. Nowadays routine diagnostics includes basic FISH approaches rather than multicolor-FISH. The latter together with modern high-throughput methods have their impact on research to identify new tumor-associated genomic regions.

State-of-the-art FISHing: automated analysis of cytogenetic aberrations in interphase nuclei

Interphase fluorescence in situ hybridization (i-FISH) is a powerful tool for visualizing various molecular targets in non-dividing cells. Manual scoring of i-FISH signals is a labor intensive, time-consuming, and error-prone process liable to subjective interpretation. Automated evaluation of signal patterns provides the opportunity to overcome these difficulties. The first report on automated i-FISH analysis has been published 20 years ago and since then several applications have been introduced in the fields of oncology, and prenatal and fertility screening. In this article, we provide an insight into the automated i-FISH analysis including its course, brief history, clinical applications, and advantages and challenges. The lack of guidelines for describing new automated i-FISH methods hampers the precise comparison of performance of various applications published, thus, we make a proposal for a panel of parameters essential to introduce and standardize new applications and reproduce previously described technologies.