Contributions
Abstract: PB1860
Type: Publication Only
Background
Hairy cell leukemia (HCL) is an uncommon form of mature B-cell neoplasm that originates from activated late B-cells. BRAF mutation associated with all cases of HCL, and 40 % papillary thyroid (PTC) cancer.
Aims
BRAF mutation is well known finding in both HCL and PTC. Although the association of both cancers (HCL &PTC) with BRAF mutation is well established in the literature, up to our knowledge, this specific combination has not been previously reported in one patient.
Methods
48-year old male, presented with bilateral hip pain found to have lytic bone lesions on both x-ray and MRI. His CBC were normal and abdominal US didn’t show any splenomegaly.Bone marrow examination and flow cytometry results confirmed the diagnosis of HCL. The patient treated with cladrabine.Responded but continue to have fever, PET CT showed abnormal uptake in thyroid.
PTC diagnosis confirmed underwent total thyroidectomy followed up with RAI 30 micori BRAF from both bone marrow biopsy and thyroid tissue which turn out positive in both.
Results
The case is unique for several reasons
1- Patient did not present with pancytopenia, which is common at presentation and reported in 50% to 70% of patients with HCL
2- He did not have splenomegaly. Splenomegaly is the most common physical finding in HCL and is reported in 70%> 100% of cases
3- HCL presenting as a lytic lesion is very uncommon
Most important the association of BRAF-positive papillary thyroid cancer.
Finding of the activating point mutation in the kinase-encoding BRAF gene in all patients with classical HCL The mutation results in substitution of adenine for thymine at position 1799 in exon 15 of the BRAF that replaces Valine (V) by glutamate (E) at amino acid 600(BRAF V600E).
Although the BRAF V600E mutation is frequently present in different neoplasms, including PTC. The BRAFV600E mutation is found to be highly specific for HCL and testing for this mutation is particularly useful in differentiating classic HCL from other B- cell neoplasm with overlapping features, such as HCL variant.
Conclusion
The presence of BRAF mutation in both papillary thyroid cancer and HCL may raise the possibility of common pathogenesis or BRAF maybe driving mutation
Session topic: 5. Chronic lymphocytic leukemia and related disorders – Biology & Translational Research
Abstract: PB1860
Type: Publication Only
Background
Hairy cell leukemia (HCL) is an uncommon form of mature B-cell neoplasm that originates from activated late B-cells. BRAF mutation associated with all cases of HCL, and 40 % papillary thyroid (PTC) cancer.
Aims
BRAF mutation is well known finding in both HCL and PTC. Although the association of both cancers (HCL &PTC) with BRAF mutation is well established in the literature, up to our knowledge, this specific combination has not been previously reported in one patient.
Methods
48-year old male, presented with bilateral hip pain found to have lytic bone lesions on both x-ray and MRI. His CBC were normal and abdominal US didn’t show any splenomegaly.Bone marrow examination and flow cytometry results confirmed the diagnosis of HCL. The patient treated with cladrabine.Responded but continue to have fever, PET CT showed abnormal uptake in thyroid.
PTC diagnosis confirmed underwent total thyroidectomy followed up with RAI 30 micori BRAF from both bone marrow biopsy and thyroid tissue which turn out positive in both.
Results
The case is unique for several reasons
1- Patient did not present with pancytopenia, which is common at presentation and reported in 50% to 70% of patients with HCL
2- He did not have splenomegaly. Splenomegaly is the most common physical finding in HCL and is reported in 70%> 100% of cases
3- HCL presenting as a lytic lesion is very uncommon
Most important the association of BRAF-positive papillary thyroid cancer.
Finding of the activating point mutation in the kinase-encoding BRAF gene in all patients with classical HCL The mutation results in substitution of adenine for thymine at position 1799 in exon 15 of the BRAF that replaces Valine (V) by glutamate (E) at amino acid 600(BRAF V600E).
Although the BRAF V600E mutation is frequently present in different neoplasms, including PTC. The BRAFV600E mutation is found to be highly specific for HCL and testing for this mutation is particularly useful in differentiating classic HCL from other B- cell neoplasm with overlapping features, such as HCL variant.
Conclusion
The presence of BRAF mutation in both papillary thyroid cancer and HCL may raise the possibility of common pathogenesis or BRAF maybe driving mutation
Session topic: 5. Chronic lymphocytic leukemia and related disorders – Biology & Translational Research