PubMed Health⌕ Search

Biomedical subjects

B Summersgill

Publications and source records attributed to B Summersgill.

4 recordsLinked to original sources
PubMed1998

Molecular cytogenetic analysis of adult testicular germ cell tumours and identification of regions of consensus copy number change.

A series of adult testicular germ cell tumours consisting of eight seminomas, 14 non-seminomas (including two cell lines) and two combined tumours was analysed by comparative genomic hybridization and, in some cases, by interphase fluorescence in situ hybridization. The gain of 12p was identified in all cases and additional material from chromosomes 7 and 8 was found in over 70% of cases, in keeping with previous analyses. Other consistent regions of gain included 1q24-q31 (50%), 2p16-pter (41%), 2q22-q32 (45%) and Xq11-q21 (50%). The loss of 1p32-p36 (36%), 9q31-qter (36%), 11q14-qter (50%), 16p (36%) and 18p (45%) and the loss of material from chromosomes 4 and 5 (50% and 36% respectively) were also found in all histological subtypes. The loss of 1p material was confirmed in four cases by interphase FISH analysis and shown, with one exception, not to involve the loss of the D1Z2 locus at 1p36.3, which is commonly deleted in paediatric germ cell tumours. An association between gain of 6q21-q24 with cases resistant to chemotherapy (P < 0.01) was observed. In addition, loss of chromosome 19 and 22 material and gain of 5q14-q23, 6q21-q24 and 13q were found at a significantly lower frequency in seminoma than non-seminoma. These regions may contain genes involved in the divergent development of seminoma and non-seminoma.

Adult↗
PubMed1998

Establishing germ cell origin of undifferentiated tumors by identifying gain of 12p material using comparative genomic hybridization analysis of paraffin-embedded samples.

An estimated 10% of adult cancer patients present with undifferentiated carcinoma. The diagnosis of germ cell tumor (GCT) in such patients can be difficult but has important implications for patient management. Male testicular GCT is characterized by an isochromosome 12p, i(12p), or additional 12p material, in some cases restricted to the 12p11.2-p12.1 region. A gain of 12p material can indicate that a tumor, which may not be present in the testis, is of germ cell origin. Formalin-fixed, paraffin-embedded samples are the most widely available material for diagnostic analysis and retrospective studies. We have compared the identification of 12p gain in snap-frozen samples with corresponding paraffin-embedded material from three clearly defined testicular GCTs using comparative genomic hybridization analysis. In this preliminary study, paraffin-embedded tumor samples of uncertain histogenesis from seven patients were then analyzed. Tumor samples from three of these patients showed a gain of 12p material, and in one patient, gain was restricted to the 12p11.2-p12 region. The clinical picture and response to therapy were generally consistent with the 12p status, though lack of 12p gain may not exclude a diagnosis of GCT.

Adenocarcinoma↗
PubMed1980

Cytogenetic follow-up study of acute non-lymphocytic leukaemia.

A cytogenetic study was made at diagnosis in 68 patients with acute non-lymphocytic leukaemia. The median survival time of the group of patients was 47 weeks. Patients with totally abnormal karyotypes in the bone marrow had a median survival of 14 weeks, whereas for those with only chromosomally normal cells the median survival was 52 weeks, and 47 weeks for those with normal and abnormal cells. Survival was not influenced by the presence or absence of clonal abnormalities. A cytogenetic follow-up study was made on 41 of these patients. One of the three patients, still in first remission after 3 years, originally had an 8;21 translocation. In general, the abnormalities present at diagnosis disappeared during remission and there was no evidence that clones of abnormal cells were produced by treatment. The chromosomal findings in relapse were not necessarily the same as those seen at diagnosis and the abnormal karyotypes found were usually not clonal in type. A simple kinetic technique, in which the yield of mitoses after 2 and 24 h is compared, may be used as an adjunct to cytogenetic studies in predicting relapse.

Adolescent↗