Limits...
PCR clonality detection in Hodgkin lymphoma.

Hebeda KM, Van Altena MC, Rombout P, Van Krieken JH, Groenen PJ - J Hematop (2009)

Bottom Line: A clonal population was found in 13 cases with the IGH FR1 and/or FR2/FR3 PCRs.Our results indicate that the present routine PCR methods are sensitive enough to detect small numbers of malignant cells in cHL.Therefore, the presence of a clonal B-cell population does not differentiate between cHL and NHL.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology 812, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands, k.hebeda@pathol.umcn.nl.

ABSTRACT
B-cell clonality detection in whole tissue is considered indicative of B-cell non-Hodgkin lymphoma (NHL). We tested frozen tissue of 24 classical Hodgkin lymphomas (cHL) with a varying tumor cell load with the multiplex polymerase chain reaction (PCR) primer sets for IGH and IGK gene rearrangement (BIOMED-2). A clonal population was found in 13 cases with the IGH FR1 and/or FR2/FR3 PCRs. Using the IGK-VJ and IGK-DE PCRs, an additional six cases had a dominant clonal cell population, resulting in a detection rate of 79% in frozen tissue. Of 12 cases, also the formalin-fixed and paraffin-embedded (FFPE) tissue was tested. Surprisingly, in eight of the 12 FFPE cases with acceptable DNA quality (allowing PCR amplification of >200 nt fragments), the IGK multiplex PCRs performed better in detecting clonality (six out of eight clonal IGK rearrangements) than the IGH PCRs (four out of nine clonal rearrangements), despite a rather large amplicon size. There was no evidence of B-cell lymphoma during follow-up of 1 to 6 years and no correlation was found between the presence of a clonal result and Epstein-Barr virus in the tumor cells. Our results indicate that the present routine PCR methods are sensitive enough to detect small numbers of malignant cells in cHL. Therefore, the presence of a clonal B-cell population does not differentiate between cHL and NHL.

No MeSH data available.


Related in: MedlinePlus

Clonality assessment. GeneScan results of the gene rearrangement profile of a cHL frozen biopsy sample (patient 12) showing clonal Ig rearrangements with multiple primer sets in a polyclonal background of B cells (a) and a polyclonal tonsil biopsy control (b)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2713492&req=5

Fig2: Clonality assessment. GeneScan results of the gene rearrangement profile of a cHL frozen biopsy sample (patient 12) showing clonal Ig rearrangements with multiple primer sets in a polyclonal background of B cells (a) and a polyclonal tonsil biopsy control (b)

Mentions: The results of the PCRs for the different target genes on frozen tissue and FFPE are summarized in Table 3. An example of GeneScan results for different targets in a control sample and a patient sample (case 12) is given in Fig. 2. Overall, 19 cases showed clonally rearranged IGH and/or IGK genes, including case 6 with a T-cell phenotype of the HRS cells. This case did not show TCR rearrangement (data not shown). Five cases remained polyclonal for all targets, and these were cases with an estimated HRS cell percentage below 10%, two even below 5%. Ten other cases with an estimated tumor cell percentage from 5% to 10% had a clonal population. Of the five polyclonal cases, four were EBV-positive (cases 20–23). The four clonal EBV-positive cHL (cases 2, 7, 12, and 14) did not show a difference in IGH or IGK detection rate compared to EBV-negative cases. All cases showed a polyclonal background in some targets, confirming the presence of reactive B cells. Analysis of the different targets revealed that 13 of the 19 clonal cases would have been detected by testing only IGH FR1–3, and FR3 was positive in only seven of these cases. Clonal IGK rearrangements were detected in six additional cases, with one clonal IGK-VJ and six clonal IGK-DE rearrangements identified. IGH-DJ showed a clonal rearrangement in two cases but was always accompanied by other rearrangements. The detection rate of clonal rearrangements in this study was 79% providing sufficient DNA quality. In 11 of the 19 clonal cHL cases, multiple (two or more) clonally rearranged targets were found. The eight cases with isolated clonal rearrangements showed either IGH FR2 (two cases), FR3 (one case), or IGK-DE (five cases).Fig. 2


PCR clonality detection in Hodgkin lymphoma.

Hebeda KM, Van Altena MC, Rombout P, Van Krieken JH, Groenen PJ - J Hematop (2009)

Clonality assessment. GeneScan results of the gene rearrangement profile of a cHL frozen biopsy sample (patient 12) showing clonal Ig rearrangements with multiple primer sets in a polyclonal background of B cells (a) and a polyclonal tonsil biopsy control (b)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2713492&req=5

Fig2: Clonality assessment. GeneScan results of the gene rearrangement profile of a cHL frozen biopsy sample (patient 12) showing clonal Ig rearrangements with multiple primer sets in a polyclonal background of B cells (a) and a polyclonal tonsil biopsy control (b)
Mentions: The results of the PCRs for the different target genes on frozen tissue and FFPE are summarized in Table 3. An example of GeneScan results for different targets in a control sample and a patient sample (case 12) is given in Fig. 2. Overall, 19 cases showed clonally rearranged IGH and/or IGK genes, including case 6 with a T-cell phenotype of the HRS cells. This case did not show TCR rearrangement (data not shown). Five cases remained polyclonal for all targets, and these were cases with an estimated HRS cell percentage below 10%, two even below 5%. Ten other cases with an estimated tumor cell percentage from 5% to 10% had a clonal population. Of the five polyclonal cases, four were EBV-positive (cases 20–23). The four clonal EBV-positive cHL (cases 2, 7, 12, and 14) did not show a difference in IGH or IGK detection rate compared to EBV-negative cases. All cases showed a polyclonal background in some targets, confirming the presence of reactive B cells. Analysis of the different targets revealed that 13 of the 19 clonal cases would have been detected by testing only IGH FR1–3, and FR3 was positive in only seven of these cases. Clonal IGK rearrangements were detected in six additional cases, with one clonal IGK-VJ and six clonal IGK-DE rearrangements identified. IGH-DJ showed a clonal rearrangement in two cases but was always accompanied by other rearrangements. The detection rate of clonal rearrangements in this study was 79% providing sufficient DNA quality. In 11 of the 19 clonal cHL cases, multiple (two or more) clonally rearranged targets were found. The eight cases with isolated clonal rearrangements showed either IGH FR2 (two cases), FR3 (one case), or IGK-DE (five cases).Fig. 2

Bottom Line: A clonal population was found in 13 cases with the IGH FR1 and/or FR2/FR3 PCRs.Our results indicate that the present routine PCR methods are sensitive enough to detect small numbers of malignant cells in cHL.Therefore, the presence of a clonal B-cell population does not differentiate between cHL and NHL.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology 812, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands, k.hebeda@pathol.umcn.nl.

ABSTRACT
B-cell clonality detection in whole tissue is considered indicative of B-cell non-Hodgkin lymphoma (NHL). We tested frozen tissue of 24 classical Hodgkin lymphomas (cHL) with a varying tumor cell load with the multiplex polymerase chain reaction (PCR) primer sets for IGH and IGK gene rearrangement (BIOMED-2). A clonal population was found in 13 cases with the IGH FR1 and/or FR2/FR3 PCRs. Using the IGK-VJ and IGK-DE PCRs, an additional six cases had a dominant clonal cell population, resulting in a detection rate of 79% in frozen tissue. Of 12 cases, also the formalin-fixed and paraffin-embedded (FFPE) tissue was tested. Surprisingly, in eight of the 12 FFPE cases with acceptable DNA quality (allowing PCR amplification of >200 nt fragments), the IGK multiplex PCRs performed better in detecting clonality (six out of eight clonal IGK rearrangements) than the IGH PCRs (four out of nine clonal rearrangements), despite a rather large amplicon size. There was no evidence of B-cell lymphoma during follow-up of 1 to 6 years and no correlation was found between the presence of a clonal result and Epstein-Barr virus in the tumor cells. Our results indicate that the present routine PCR methods are sensitive enough to detect small numbers of malignant cells in cHL. Therefore, the presence of a clonal B-cell population does not differentiate between cHL and NHL.

No MeSH data available.


Related in: MedlinePlus