Cytogenetic Screening for Monosomy 7

Diagnostic Testing and Risk Stratification

The European LeukemiaNet recommends conventional cytogenetic analysis (G-banding) of bone marrow aspirate with analysis of at least 20 metaphases to detect monosomy 7, as this abnormality is one of the most critical prognostic factors determining treatment strategy 1, 2, 3
The International Prognostic Scoring System (IPSS) classifies monosomy 7 in the adverse risk category, and the European LeukemiaNet (ELN) 2017 guidelines for AML also consider monosomy 7 as a high-risk feature 2, 3
The presence of monosomy 7 provides presumptive evidence of myelodysplastic syndrome (MDS) even in the absence of definitive morphologic features, with a strength of evidence level of high 3
FISH analysis for monosomy 7 is mandatory in specific clinical scenarios where conventional cytogenetics fails or rapid results are needed, with a sensitivity of 80-90% 1, 3

The American Society of Hematology recommends allogeneic hematopoietic stem cell transplantation (HSCT) as the only potentially curative therapy for most patients with monosomy 7, with a level of evidence of 1A 6
Intensive chemotherapy alone has historically shown poor outcomes in monosomy 7 cases, with frequent treatment resistance and early relapse, and should not be considered definitive therapy, with a level of evidence of 1B 6

The National Comprehensive Cancer Network (NCCN) recommends serial somatic gene panels from bone marrow specimens at baseline and with each subsequent evaluation for patients with germline predisposition syndromes, including Fanconi Anemia, GATA2 deficiency, and severe congenital neutropenia 6
High-resolution molecular HLA typing (classes I and II) should be performed at diagnosis for patients aged <55 years who are candidates for allogeneic HSCT, with a level of evidence of 2A 6

In pediatric patients, monosomy 7 is a critical marker of malignant transformation, and FISH for monosomy 7 detection is specifically recommended due to the prognostic value of this aberration, with a level of evidence of 2B 1
In patients with germline predisposition syndromes, such as GATA2 deficiency and Fanconi Anemia, monosomy 7 is a high-risk feature strongly associated with malignant transformation, and allogeneic HSCT is recommended, with a level of evidence of 1A 6