Considering the growing interest in matched cancer treatment, our aim was to evaluate the ability of a comprehensive genomic profiling (CGP) assay to propose at least one targeted therapy given an ...identified genomic alteration or signature (actionability), and to collect the treatment modifications based on the CGP test results in clinical practise for solid tumors. This retrospective, multicentre French study was conducted among 25 centres that participated in a free of charge program between 2017 and 2019 for a tissue CGP test. Data were collected on the patient, disease, tumor genomic profile, treatment suggested in the report (related to the genomic profile results) and subsequent therapeutic decisions according to the physician's declaration. Among the 416 patients, most had lung cancer (35.6%), followed by biliary tract cancer (11.5%) or rare cancers (11.1%); 75% had a metastatic disease. The actionability was 75.0% (95% CI 70.6%-78.9%) for all patients, 85.1% and 78.4%, respectively in lung cancer and metastatic patients. After exclusion of clinical trial suggestions, the actionability decreased to 62.3% (95% CI 57.5%-66.8%). Treatment modification based on the test results was observed in 17.3% of the patients and was more frequent in metastatic disease (OR = 2.73, 95% CI 1.31-5.71, p = 0.007). The main reasons for no treatment modification were poor general condition (33.2%) and stable disease or remission (30.2%). The genomic-directed treatment changes were performed mostly during the first six months after the CGP test, and interestingly a substantial part was observed from six to 24 months after the genomic profiling. This French study provides information on the real-life actionability of a CGP test based on tissue samples, and trends to confirm its utility in clinical practice across the course of the disease, in particularly for patients with lung cancer and/or advanced disease.
IntroductionConsidering the growing interest in matched cancer treatment, our aim was to evaluate the ability of a comprehensive genomic profiling (CGP) assay to propose at least one targeted therapy ...given an identified genomic alteration or signature (actionability), and to collect the treatment modifications based on the CGP test results in clinical practise for solid tumors.MethodsThis retrospective, multicentre French study was conducted among 25 centres that participated in a free of charge program between 2017 and 2019 for a tissue CGP test. Data were collected on the patient, disease, tumor genomic profile, treatment suggested in the report (related to the genomic profile results) and subsequent therapeutic decisions according to the physician's declaration.ResultsAmong the 416 patients, most had lung cancer (35.6%), followed by biliary tract cancer (11.5%) or rare cancers (11.1%); 75% had a metastatic disease. The actionability was 75.0% (95% CI 70.6%-78.9%) for all patients, 85.1% and 78.4%, respectively in lung cancer and metastatic patients. After exclusion of clinical trial suggestions, the actionability decreased to 62.3% (95% CI 57.5%-66.8%). Treatment modification based on the test results was observed in 17.3% of the patients and was more frequent in metastatic disease (OR = 2.73, 95% CI 1.31-5.71, p = 0.007). The main reasons for no treatment modification were poor general condition (33.2%) and stable disease or remission (30.2%). The genomic-directed treatment changes were performed mostly during the first six months after the CGP test, and interestingly a substantial part was observed from six to 24 months after the genomic profiling.ConclusionThis French study provides information on the real-life actionability of a CGP test based on tissue samples, and trends to confirm its utility in clinical practice across the course of the disease, in particularly for patients with lung cancer and/or advanced disease.
This report summarizes a cumulative 4-year experience in polymerase chain reaction (PCR) analysis of immunoglobin heavy chain (IgH) and TcR-γ chain gene rearrangements in 525 cases of ...lymphoproliferative disorders. Because the sensitivity of the PCR methodology was found to be tissue dependent, in the study of the presence of clonal cell population in tissues containing a small number of polyclonal lymphocytes, such as skin and gastrointestinal biopsy specimens, we used the multiple–PCR run approach. In this latter methodology, we repeat the PCR reaction from the same sample at least three times to confirm the reproducibility of the results. In the study of 273 cases of B- or T-cell lymphomas with characteristic immunomorphological and clinical features, a clonal IgH or TcR-γ chain gene rearrangement was detected in approximately 80% of cases. A clonal rearrangement involving both IgH and TcR-γ chain genes was found in 10% of cases of both B-cell and T-cell lymphomas. The study of 167 cases of nonneoplastic lymphoid tissue samples showed the presence of clonally rearranged cell populations for IgH or TcR-γ genes in 3 and 9% of cases, respectively. We also applied PCR for the study of 85 cases of lymphoproliferations with no definite diagnosis (i.e., benign versus malignant) after immunomorphological analysis. In 65 cases (76%), the correlation of immunomorphological features with the presence (48 cases) or the absence (17 cases) of clonal lymphoid cell populations led to a definite diagnosis. In almost all these cases, the final diagnosis was found to be in agreement with the clinical course. In the 20 remaining cases (24%), no definite diagnosis could be made. We also assessed the value of PCR in detecting bcl-2/JH gene rearrangement as an additional clonal marker in the diagnosis of follicular lymphoma. Bcl-2/JH rearrangement and/or IgH gene rearrangement was found in approximately 85% (71/85) of follicular lymphoma cases studied.
The expression of the apoptosis-regulating genes Bcl-2, Bcl-x, Bax, Mcl-1, and p53 analyzed in 4 cases of human immunodeficiency virus (HIV)-associated Hodgkin's disease, in 36 cases of HIV-related ...non-Hodgkin's lymphomas (NHLs), and in 109 cases of non-HIV-related NHLs by using immunohistochemistry. HIV-associated Hodgkin's disease samples were positive for all markers. For the HIV-related NHL samples, 36, 66, 88, 100, and 94% of the cases were Bcl-2, Bcl-x, Bax, Mcl-1, and p53 were found to be expressed in 69, 65, 82, 83, and 42%, respectively. No significant differences were observed in Bax and Mcl-1 staining between HIV-unrelated NHLs of B cell and T cell types. In contrast, Bcl-2 was positive in 66/79 (83%) and 10/30 (33%) of B cell and T cell HIV-unrelated NHLs, respectively (P2 < 0.001). Peculiar patterns were observed for hairy cell leukemia (Bax+, Bcl-2+, Mcl-1-) and for anaplastic large cell lymphoma (Bax+, Mcl-1+, Bcl-2-) in HIV-unrelated NHLs. Of interest, all cases with a positive expression of Bax were also found to express either Mcl-1 and/or Bcl-2, suggesting that Mcl-1 and Bcl-2 may counteract the pro-apoptosis function of Bax in vivo by protein-protein interaction within the tumor cell, as demonstrated previously in vitro. These results suggest that apoptosis regulation may have a role in the pathogenesis of some HIV-related and HIV-unrelated NHLs.
In the search of B‐cell lymphoma/leukaemia dissemination to cerebrospinal fluid (CSF), we used the highly sensitive semi‐nested PCR (snPCR) for the analysis of IgH gene rearrangements. This method ...detects a rearranged IgH gene from a single B lymphocyte which may or may not represent the neoplastic B‐cell population. We therefore performed multiple snPCR (three to five) experiments on the same CSF sample, postulating that the detection of a band of the same size and sequence in different PCR runs was highly indicative of a clonal population. 17 consecutive cases with a differential diagnosis of primary (PcnsL) (n=10) or secondary (ScnsL) (n=7) CNS lymphoma or leukaemia were investigated by the new strategy. The clonal nature of the B‐cell population was confirmed in 3/10 of suspected PcnsL, and in six other cases the PCR study was indicative of reactive lymphocytosis. One case revealed a clonal B‐cell population in the clinical context of an autoimmune disorder. Evidence of clonal B‐cell population was found in 4/7 of suspected ScnsL. In one of these cases the detected band and its sequence proved identical to that of the primary nodal lymphoma. We believe that the evaluation of B‐cell clonality in CSF requires multiple snPCR amplification on the same sample to compare the size of the products and, if necessary, the DNA sequences to ascertain the diagnosis of malignancy in equivocal cytologic and clinical findings.
Follicular lymphomas are often associated with t(14;18) chromosomal translocation. The rearrangement site (bcl-2/JH junctional region) between the two chromosomes is hypervariable regarding its size ...and DNA sequence, and is a potential specific marker for the neoplastic clone of each patient. We report the use of the polymerase chain reaction (PCR) technique for detecting and sequencing clonal bcl-2/JH rearrangements in lymph nodes and/or bone marrow specimens from patients with follicular lymphoma. 53 patients at diagnosis (n = 40) or at relapse (n = 13) were studied. 25 of these 53 cases were found to have the t(14;18) translocation involving either the major breakpoint region (MBR) (n = 21) or the minor cluster region (mcr) (n = 4). Since our PCR technique could detect the translocation in 1/10(6) cells we had to distinguish malignant cells from possible t(14;18)-bearing non-malignant cells which could be present during and after treatment. The bcl-2/JH junctional regions were therefore sequenced in order to synthesize an anti-junction oligonucleotide probe specific for each patient's malignant clone (clonospecific probe). Using these clonospecific probes for hybridization it was possible to detect one malignant cell mixed with 10(6) normal cells. 28 patients with advanced stage (stage III and IV), had been enrolled for treatment with myeloablative chemoradiotherapy and autologous bone marrow transplantation (ABMT). In 12 of these patients bcl-2/MBR translocation was found at diagnosis and used as a marker to detect the presence of residual lymphoma cells in serial bone marrow (BM) and peripheral blood (PB) samples. In three relapsed patients (with available tissue samples at diagnosis and relapse), clonospecific probes clearly demonstrated the same bcl-2/JH junction, thus confirming that the relapse occurred from the same malignant clone, and which remained stable without any clonal evolution of its junctional region throughout the course of the disease. These results demonstrate the value of the t(14;18) clonospecific probes as a diagnostic tool in the detection of minimal residual disease and relapses in patients with follicular lymphoma.
This report summarizes a cumulative 4-year experience in polymerase chain reaction (PCR) analysis of immunoglobin heavy chain (IgH) and TcR-gamma chain gene rearrangements in 525 cases of ...lymphoproliferative disorders. Because the sensitivity of the PCR methodology was found to be tissue dependent, in the study of the presence of clonal cell population in tissues containing a small number of polyclonal lymphocytes, such as skin and gastrointestinal biopsy specimens, we used the multiple-PCR run approach. In this latter methodology, we repeat the PCR reaction from the same sample at least three times to confirm the reproducibility of the results. In the study of 273 cases of B- or T-cell lymphomas with characteristic immunomorphological and clinical features, a clonal IgH or TcR-gamma chain gene rearrangement was detected in approximately 80% of cases. A clonal rearrangement involving both IgH and TcR-gamma chain genes was found in 10% of cases of both B-cell and T-cell lymphomas. The study of 167 cases of nonneoplastic lymphoid tissue samples showed the presence of clonally rearranged cell populations for IgH or TcR-gamma genes in 3 and 9% of cases, respectively. We also applied PCR for the study of 85 cases of lymphoproliferations with no definite diagnosis (i.e., benign versus malignant) after immunomorphological analysis. In 65 cases (76%), the correlation of immunomorphological features with the presence (48 cases) or the absence (17 cases) of clonal lymphoid cell populations led to a definite diagnosis. In almost all these cases, the final diagnosis was found to be in agreement with the clinical course. In the 20 remaining cases (24%), no definite diagnosis could be made. We also assessed the value of PCR in detecting bcl-2/J(H) gene rearrangement as an additional clonal marker in the diagnosis of follicular lymphoma. Bcl-2/J(H) rearrangement and/or IgH gene rearrangement was found in approximately 85% (71/85) of follicular lymphoma cases studied.
This report summarizes a cumulative 4-year experience in polymerase chain reaction (PCR) analysis of immunoglobin heavy chain (IgH) and TcR-g chain gene rearrangements in 525 cases of ...lymphoproliferative disorders. Because the sensitivity of the PCR methodology was found to be tissue dependent, in the study of the presence of clonal cell population in tissues containing a small number of polyclonal lymphocytes, such as skin and gastrointestinal biopsy specimens, we used the multiple-PCR run approach. In this latter methodology, we repeat the PCR reaction from the same sample at least three times to confirm the reproducibility of the results. In the study of 273 cases of B- or T-cell lymphomas with characteristic immunomorphological and clinical features, a clonal IgH or TcR-g chain gene rearrangement was detected in approximately 80% of cases. A clonal rearrangement involving both IgH and TcR-g chain genes was found in 10% of cases of both B-cell and T-cell lymphomas. The study of 167 cases of nonneoplastic lymphoid tissue samples showed the presence of clonally rearranged cell populations for IgH or TcR-g genes in 3 and 9% of cases, respectively. We also applied PCR for the study of 85 cases of lymphoproliferations with no definite diagnosis (i.e., benign versus malignant) after immunomorphological analysis. In 65 cases (76%), the correlation of immunomorphological features with the presence (48 cases) or the absence (17 cases) of clonal lymphoid cell populations led to a definite diagnosis. In almost all these cases, the final diagnosis was found to be in agreement with the clinical course. In the 20 remaining cases (24%), no definite diagnosis could be made. We also assessed the value of PCR in detecting bcl-2/J sub(H) gene rearrangement as an additional clonal marker in the diagnosis of follicular lymphoma. Bcl-2/J sub(H) rearrangement and/or IgH gene rearrangement was found in approximately 85% (71/85) of follicular lymphoma cases studied.Mod Pathol 2000; 13(12):1269-1279
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