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Stephen J Qualman

Publications and source records attributed to Stephen J Qualman.

27 records · Page 2Linked to original sources

Children from ethnic minorities have benefited equally as other children from contemporary therapy for rhabdomyosarcoma: a report from the Intergroup Rhabdomyosarcoma Study Group.

PURPOSE: To define the clinical characteristics of rhabdomyosarcoma (RMS) occurring in children from ethnic minorities and determine whether these children have benefited equally from advances in therapy. PATIENTS AND METHODS: This was a retrospective cohort analysis of children treated on the Intergroup Rhabdomyosarcoma Study Group protocols between 1984 and 1997. The clinical features and outcomes of 336 African-American children and 286 children from other ethnic minorities were compared with those of white children (n = 1,721). RESULTS: African-American, other ethnic group, and white children enjoyed similar 5-year failure-free survivals (FFS) of 61%, 61%, and 66%, respectively, P =.15. Compared with white children, nonwhite patients more often had (1) invasive, T2 tumors (P =.03); (2) stage 2 or 3 tumors (P =.003); (3) large tumors (more than 5 cm, P <.006); and/or (4) tumors with positive regional nodes (ie, N1, P =.002). Using Cox proportional hazards analysis, seven patient risk categories were defined with significant differences in outcome. This model was then used to search for other factors associated with FFS after adjusting for these risk categories. Only T stage and age remained associated with FFS (P =.001 and P <.001, respectively). After adjusting for T stage, risk category, and age, we explored the relationship of ethnic group to FFS and found that, compared with whites, the relative risk of failure was 1.14 for African-American patients and 1.2 for other ethnic minority patients, values that are not significantly different. CONCLUSION: Patients from ethnic minority groups more often have larger, invasive tumors with positive lymph nodes. Nevertheless, they have benefited as equally as white children from the dramatic progress in therapy of RMS.

Black or African American↗

Genetic heterogeneity in the alveolar rhabdomyosarcoma subset without typical gene fusions.

Previous studies of the PAX3-FKHR and PAX7-FKHR gene fusions in alveolar rhabdomyosarcoma (ARMS) indicated that the corresponding fusiontranscripts are not detectable in 20% of ARMS cases. To investigate the genetic features of this ARMS subset, we identified 23 ARMS cases in which PAX3-FKHR and PAX7-FKHR transcripts were not detected by a standard sensitivity reverse transcription-PCR (RT-PCR) assay. Subsequent analysis with a high sensitivity RT-PCR assay identified low-level expression of PAX3-FKHR or PAX7-FKHR in three cases. Analysis with a Southern blot assay for PAX3 and PAX7 rearrangements and a fluorescence in situ hybridization assay for FKHR rearrangements identified three cases with variant fusions in which PAX3 or PAX7 is postulated to be joined to novel genomic loci. In one such case, RT-PCR analysis of candidate partners identified a fusion of PAX3 to AFX, which is highly similar in structure and function to FKHR. Additional fluorescence in situ hybridization analysis identified two cases in which a PAX3-FKHR or PAX7-FKHR genomic fusion is present but is not associated with a fusion transcript detectable by RT-PCR. Finally, our analyses of the PAX3, PAX7, and FKHR loci did not identify rearrangements in >50% of cases, consistent with the possibility that there is a true fusion-negative subset. In summary, our analysis of ARMS cases without characteristic PAX3-FKHR or PAX7-FKHR transcripts identified several genetically distinct subsets including low expression or atypical presentation of standard fusions, variant fusions with other genes, and possibly true fusion-negative cases.

Base Sequence↗

PAX3-FKHR and PAX7-FKHR gene fusions are prognostic indicators in alveolar rhabdomyosarcoma: a report from the children's oncology group.

PURPOSE: Alveolar rhabdomyosarcoma (ARMS) is an aggressive soft tissue malignancy of children and adolescents. Most ARMS patients express PAX3-FKHR or PAX7-FKHR gene fusions resulting from t(2;13) or t(1;13) translocations, respectively. We wished to confirm the diagnostic specificity of gene fusion detection in a large cohort of RMS patients and to evaluate whether these alterations influence clinical outcome in ARMS. PATIENTS AND METHODS: We determined PAX3-FKHR or PAX7-FKHR fusion status in 171 childhood rhabdomyosarcoma (RMS) patients entered onto the Intergroup Rhabdomyosarcoma Study IV, including 78 ARMS patients, using established reverse transcriptase polymerase chain reaction assays. All patients received central pathologic review and were treated using uniform protocols, allowing for meaningful outcome analysis. We examined the relationship between gene fusion status and clinical outcome in the ARMS cohort. RESULTS: PAX3-FKHR and PAX7-FKHR fusion transcripts were detected in 55% and 22% of ARMS patients, respectively; 23% were fusion-negative. All other RMS patients lacked transcripts, confirming the specificity of these alterations for ARMS. Fusion status was not associated with outcome differences in patients with locoregional ARMS. However, in patients presenting with metastatic disease, there was a striking difference in outcome between PAX7-FKHR and PAX3-FKHR patient groups (estimated 4-year overall survival rate of 75% for PAX7-FKHR v 8% for PAX3-FKHR; P =.0015). Multivariate analysis demonstrated a significantly increased risk of failure (P =.025) and death (P =.019) in patients with metastatic disease if their tumors expressed PAX3-FKHR. Among metastatic ARMS, bone marrow involvement was significantly higher in PAX3-FKHR-positive patients. CONCLUSION: Not only are PAX-FKHR fusion transcripts specific for ARMS, but expression of PAX3-FKHR and PAX7-FKHR identifies a very high-risk subgroup and a favorable outcome subgroup, respectively, among patients presenting with metastatic ARMS.

Adolescent↗

Genomic gains and losses are similar in genetic and histologic subsets of rhabdomyosarcoma, whereas amplification predominates in embryonal with anaplasia and alveolar subtypes.

In this investigation, we selected PAX3/FKHR and PAX7/FKHR fusion transcript-positive and -negative alveolar rhabdomyosarcomas (ARMSs) and embryonal rhabdomyosarcomas (ERMSs) with and without anaplastic features, to ascertain genomic imbalance differences and/or similarities within these histopathologic and genetic rhabdomyosarcoma (RMS) variants. Comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) studies were performed on 45 rhabdomyosarcoma specimens consisting of 23 ARMSs and 22 ERMSs (12 ERMS cases were included from an earlier study). The anaplastic variant of RMS has not previously been subjected to CGH analysis. Overall, the most prominent imbalances were gain of chromosomes or chromosomal regions 2/2q (40%), 7/7q (31%), 8/8p (53%), 11/11q (31%), 12q13-15 (49%), 13q14 (22%), and 20/20p (31%), and loss of 1p36 (27%), 3p14-21 (22%), 9q21-22 (33%), 10q22-qter (18%), 16q (27%), 17p (22%), and 22 (22%). These gains and losses were distributed equally between ARMS and ERMS histologic subtypes (excluding 7/7q and 11/11q gain that were observed chiefly in ERMS), demonstrating that these entities are similar with respect to recurrent genomic imbalances. Moreover, genomic imbalances were also evenly distributed among the ARMS fusion transcript subtypes, providing evidence for a genetic kinship despite the absence of a fusion transcript in some cases. Genomic amplification was detected in 26% and 23% of the ARMS and ERMS cases, respectively (with nearly all of the latter subset exhibiting anaplastic features). One amplicon, involving 15q25-26, corresponds to the locus of the insulin-like growth factor type I receptor (IGF1R) gene. Amplification of IGF1R was confirmed molecularly in the cases exhibiting a 15q25-26 amplicon. In summary, these results indicate that genomic gains and losses involve alike chromosomes with similar frequencies within the histopathologic and genetic subtypes of rhabdomyosarcoma, that genomic amplification is frequent not only in the alveolar histologic subtype of rhabdomyosarcoma but also in ERMS with anaplasia, and that amplification of IGF1R possibly plays a role in the development or progression of a subset of rhabdomyosarcomas.

Adolescent↗

Treatment of children and adolescents with localized parameningeal sarcoma: experience of the Intergroup Rhabdomyosarcoma Study Group protocols IRS-II through -IV, 1978-1997.

BACKGROUND: We reviewed 611 patients with parameningeal sarcoma entered on Intergroup Rhabdomyosarcoma Study Group (IRSG) Protocols-II through IV (1978-1997), to delineate treatment results and evaluate prognostic factors. PROCEDURE: Primary sites were the middle ear/mastoid (N = 138), nasopharynx/nasal cavity (N = 235), paranasal sinuses (N = 132), parapharyngeal region (N = 29), and the pterygopalatine/infratemporal fossa (N = 77). Treatment was initial biopsy or surgery followed by multiagent chemotherapy and radiation therapy (XRT). Beginning in 1977, patients with cranial nerve palsy, cranial base bony erosion, and/or intracranial extension at diagnosis were considered as having meningeal involvement. They received triple intrathecal medications, whole brain XRT, and then spinal XRT. These treatments were successively eliminated from 1980 to 1991. RESULTS: The 611 patients' overall survival rate at 5 years was 73% (95% confidence interval, 70-77%). Favorable prognostic factors were: age 1-9 years at diagnosis; primary tumor in the nasopharynx/nasal cavity, middle ear/mastoid, or parapharyngeal areas; no meningeal involvement; and non-invasive tumors (T1). Thirty-five of 526 patients (6.7%) with information about presence/absence of meningeal involvement at diagnosis developed central nervous system (CNS) extension at 5-164 weeks (median, 46 weeks) after starting therapy. The estimated 5-year cumulative incidence rate of CNS extension during the study period was 5-7% (P = 0.88). CONCLUSIONS: Biopsy, XRT to the target volume, and systemic chemotherapy are successful treatments for the large majority of patients with localized parameningeal sarcoma. Carefully defining and irradiating the initial volume should reduce the risk of CNS failure. Aggressive initial surgical management of these patients is unnecessary.

Adolescent↗

Risk assignment in pediatric soft-tissue sarcomas: an evolving molecular classification.

Pediatric soft-tissue sarcomas are increasingly being defined by both histologic appearance and underlying chromosomal abnormalities to determine their biologic behavior. Most sarcomas of this type have specific chromosomal translocations that create unique fusion genes. Expression of such fusion genes may have diagnostic, prognostic, and surveillance implications for the patient. This review analyzes the fusion gene expressions seen with seven of the major types of pediatric soft-tissue tumors and their impact on biologic behavior. In nearly 50% of the malignancies discussed, the diagnostic, prognostic, and surveillance implications of their specific fusion gene expressions are already defined or becoming established (alveolar rhabdomyosarcoma, Ewing sarcoma/primitive neuroectodermal tumor, and synovial sarcoma). In the remainder of the tumors, these questions are rapidly being addressed. To facilitate future fusion gene studies, pediatric surgeons, pathologists, and oncologists need to work as a coordinated team to ensure proper tumor procurement. Large clinical cooperative trials involving biologic studies of pediatric soft-tissue sarcomas could facilitate advancement of knowledge in this area of pediatric oncology.

Adolescent↗

Cutaneous lymphoblastic lymphoma in children: report of six cases with precursor B-cell lineage.

Precursor B lymphoblastic lymphomas (B-LBL) are generally rare, but appear to have a higher incidence in children than in adults. In this report, we describe in detail six cases of B-LBL presenting with cutaneous lesions. Three occurred in the scalp, one in the skin of the thigh, one in the skin of the face and breast, and one in the subcutaneous tissue of the orbit. All six patients are females ranging in age at presentation from 5 to 15 years (mean = 9.6). None of the cases had bone marrow involvement, while two had bone involvement (maxilla, distal tibia, and distal humerus in one case, and distal tibia and orbital bone in another case); only one case had lymphadenopathy (retroperitoneal). Immunohistochemical staining showed positivity for CD79a and CD43 in all six cases. LCA and L26 positivity were also each seen in one case. Staining for MIC-2 (CD99) showed strong positivity in three cases. Vimentin was positive in four cases and TdT was positive in all five patients tested. Staining for keratin, UCHL-1, or CD30 was not encountered. Cases in which cell marker studies by flow cytometry were performed showed positivity for CD10, CD19 with negative CD20, pan-T-cell, and myeloid markers. The five patients who received multiagent chemotherapy are alive with follow-up intervals of 2 to 18 years. Two patients had local recurrences and were given radiation therapy (one with repeating multiagent chemotherapy). One patient (diagnosed in 1962) died of disseminated disease; she had been treated with radiation therapy and 6MP only. Cutaneous B-LBL must be included in the differential diagnosis of small blue cell tumors, especially in children. In contrast to its T-cell counterpart, B-LBL occurs more frequently in females, tends to present as skin or bone lesions, and is associated with a potential cure, even in cases that relapse.

Adolescent↗