Chemoresistance can be overcome with high-dose chemotherapy and autologous stem-cell transplantation for relapsed and refractory Hodgkin lymphoma.

BACKGROUND: High-dose therapy and autologous stem-cell transplant (HDT/ASCT) is the preferred treatment of chemosensitive relapsed/refractory Hodgkin lymphoma (HL). The role for HDT/ASCT in chemoresistant HL is less well defined. We evaluated long-term outcomes of relapsed/refractory HL patients whose disease was refractory to secondary chemotherapy preceding HDT/ASCT. PATIENTS AND METHODS: All HL patients who underwent HDT/ASCT in British Columbia for primary progression (PP, defined as progression within 3 months of initial therapy completion) or first relapse (REL1) were reviewed. Patients were grouped based on response to secondary chemotherapy as sensitive (S), resistant (R), and untested/unknown (U). RESULTS: A total of 256 patients underwent HDT/ASCT for PP (35%) or REL1 (65%) between 1985 and 2011. At median follow-up of 11.7 years, 58% were alive without HL, 36% relapsed; 6% died of transplant-related mortality, 3% secondary malignancies, and 3% unrelated causes. For PP/S, PP/R, and PP/U groups, 10-year FFS were 47%, 31%, and 38%; 10-year OS were 52%, 29%, and 37%, respectively. For REL1/S, REL1/R, and REL1/U groups, 10-year FFS were 64%, 51%, and 81%; 10-year OS were 71%, 59%, and 79%, respectively. In multivariate analysis, resistance to secondary chemotherapy predicted for post-transplant mortality in the PP (P = 0.04) but not REL1 (P = 0.16) groups. CONCLUSION: In this large uniformly treated cohort of HL patients with long-term follow-up, chemoresistance preceding HDT/ASCT was identified as a poor prognostic factor; however, this factor can be partially overcome by HDT/ASCT, resulting in cure in 30%-50% of patients. HDT/ASCT should therefore be considered in all transplant eligible patients, regardless of responsiveness to salvage chemotherapy.

Predictors of outcome following myeloablative allo-SCT for therapy-related myelodysplastic syndrome and AML.

Administration of alkylating agents (Alk), topoisomerase II inhibitors (Topo II) and radiotherapy (RT) can result in therapy-related myelodysplastic syndrome or acute myelogenous leukaemia (t-MDS/t-AML), the optimal treatment for which is allo-SCT. A retrospective review was performed of 24 patients who underwent related- or unrelated-donor SCT for t-MDS/t-AML at our institution. Eight patients remain alive and in continuous remission (median follow-up 54 months (range, 12-161)) with estimated 5-year EFS being 30% (95% confidence intervals 16-58%). Corresponding actuarial risks of relapse and non-relapse mortality (NRM) are 39% (19-60%) and 30% (13-50%), respectively. EFS was 40% in Alk/RT-related t-MDS/t-AML and 11% in Topo II-related t-MDS/t-AML (P=0.05), with an increased risk of relapse in the latter (56 vs 29%, respectively (P=0.05)). In multivariate analysis, development of acute GVHD (P=0.009) and Topo II-related t-MDS/t-AML (P=0.018) were associated with inferior EFS. Patients with acute GVHD had an increased risk of NRM (P=0.03) whereas risk of relapse was higher for patients of advanced age (P=0.046) and for patients who underwent bone marrow (vs blood) SCT (P=0.032). Allo-SCT can result in long-term survival for individuals with t-MDS/t-AML although outcome in Topo II-related t-MDS/t-AML patients remains suboptimal.

A molecular and FISH analysis of structurally abnormal Y chromosomes in patients with Turner syndrome.

Fourteen patients with Turner syndrome and a structurally abnormal Y chromosome were analysed by PCR amplification and fluorescence in situ hybridisation for the presence of sequences specific to defined regions of the Y chromosome. Thirteen patients had a mosaic karyotype including a 45,X cell line and one case was non-mosaic in cultured lymphocytes. Ten patients had a pseudodicentric Yp chromosome, two an isodicentric Yq, one a pseudodicentric Yq, and one a derived Y chromosome. Two of the patients with a psu dic(Yp) chromosome had complex karyotypes with more than two cell lines, one of which exhibited five morphologically distinct mar(Y) chromosomes, presumably derived from a progenitor psu dic(Yp). Nine of the ten psu dic(Yp) chromosomes were positive for all Yp and Yq probes used except DYZ1 which maps to Yq12, suggesting a common breakpoint near the Yq euchromatin/heterochromatin boundary. In the three patients with a dicentric Yq chromosome two different breakpoints were observed; in two it was between PABY and the subtelomeric repeat sequence and in one it was between DYZ5 and AMGY in proximal Yp. Our results suggest that the great majority of structurally abnormal Y chromosomes found in Turner syndrome mosaics contain two copies of virtually all of the functional Y chromosome euchromatin.

Research on screening and diagnosis in autism: a work in progress.

In June 1998, the National Institutes of Health Autism Coordinating Committee (NIH/ACC) invited representatives of 13 major medical and other professional academies and associations and six national autism parent research organizations to review research data on screening and diagnosis of autism spectrum disorders. Ten review papers and more than 4,000 publications were consulted in this effort. This paper highlights some promising areas for research identified in this process. One of the highest priorities is the search for the ultimate diagnostic indicator, a biological marker(s), for example, genetic, metabolic, immunologic, neurologic, that will distinguish autism unequivocally from other developmental disabilities. In the interim, research on infant screening and diagnosis might lower the threshold age for diagnosis to 8-12 months. The role of sensory-motor disorders in early diagnosis needs further research. Earlier and better diagnosis of co-occurring, potentially treatable disorders, including epileptic and epileptiform disorders, has implications both for diagnosis and treatment. Pharmacogenetic and pharmacogenomic research strategies could help diagnose subtypes and responders versus nonresponders to potential treatments. Better endpoints and outcome measures are needed, including improved procedures for cognitive and neuropsychological testing, more knowledge about verbal and nonverbal communication milestones, and less invasive and more sensitive neuroimaging measures. Critical questions remain regarding regression after apparently normal development, and about possible environmental precipitants. Finally, field trials of the reliability and validity of screening and diagnosis using the newly developed practice guidelines are needed.

RDCI, the vasoactive intestinal peptide receptor: a candidate gene for the features of Albright hereditary osteodystrophy associated with deletion of 2q37.

Albright hereditary osteodystrophy (AHO) is an autosomal dominant disorder characterised by the presence of brachymetaphalangism, short stature, obesity, and mental retardation. Variable biochemical changes many represent either pseudohypoparathyroidism (PHP) owing to resistance to parathormone (PTH) or pseudopseudohypoparathyroidism (PPHP) with no hormone resistance. In most cases of AHO, reduced levels of Gs alpha have been found and a number of deactivating mutations in the gene for Gs alpha located on chromosome 20q13 have been described. Recently a number of people with an AHO-like phenotype have been reported in whom a deletion of chromosomal region 2q37 has been found in the absence of biochemical abnormalities or a reduction in Gs alpha activity. We present a further female patient with a cytogenetically visible deletion of 2q37, an AHO-like phenotype, and unusual biochemistry suggesting moderate PTH resistance. The vasoactive intestinal peptide receptor (RDCI) has recently been mapped to 2q37 and we propose that this is a candidate gene, hemizygosity of which affects signal transduction and leads to the AHO-like phenotype found in patients with 2q37 deletions.

Synaptonemal complex analysis of an autosomal trisomy in the horse.

Synaptonemal complex analysis by electron microscopy of a trisomy 28 in a male horse demonstrated a trivalent or a bivalent plus a univalent in primary spermatocytes. Two of the chromosomes making up the trivalent were, most often, completely paired with each other and only partially paired or associated with the third one. Half of the spermatocytes analysed demonstrated heterologous pairing or association between the free axis of the trivalent and the sex bivalent. The pairings remained, to a large extent, into diakinesis-metaphase I. In most pachytene cells one autosomal bivalent showed proximal asynapsis and paired often, heterologously, with the trivalent or the sex bivalent. The horse demonstrated azoospermy, which was due, at least in part, to degeneration at both the spermatocyte and spermatid levels.

Standard karyotype of the domestic horse (Equus caballus). Committee for standardized karyotype of Equus caballus. The Second International Conference for Standardization of Domestic Animal Karyotypes, INRA, Jouy-en Josas, France, 22nd-26th May 1989.

The following decisions concerning the banded karyotype of the horse (Equus caballus) were made at the second International conference for Standardization of Domestic Animal Karyotypes, held at Jouy-en Josas, France, 22nd-26th May 1989: (1) numbering of the chromosomes was modified to correspond to an arrangement into only two groups (the non-acrocentrics and the acrocentrics) within which the autosomes are placed according to length alone; (2) a more compact karyotype arrangement was adopted: chromosomes 1 to 5 on the first row, 6 to 10 on the second, 11 to 13, and, at the far right, X and Y on the third row, 14 to 19 on the fourth row, chromosomes 20 to 25 on the fifth, and 26 to 31 on the sixth row; (3) the NOR-bearing horse chromosomes were identified as numbers 1, 28 and 31.

Y chromosome length variation and its significance in the horse.

The results of Y chromosome measurements in 31 horses are presented. The Y chromosome was identified using G-, R-, and C-banding techniques. From G-banded metaphase spreads, total X and Y chromosome and separate proximal (P) and distal (D) Y-band measurements were made. Within this group, the Y/X ratio (%) for each animal varied from 18.93 to 43.95, with an overall mean of 34.85 and a coefficient of variation (CV) of 16.12. The overall mean P/X ratio (%) was 23.57 with a CV of 20.57, compared with an overall mean D/X ratio (%) of 11.26 with a CV of 15.18. The group studied included 27 Thoroughbred and 4-non-Thoroughbred animals, of which 20 were clinically normal controls and 11 presented with various clinical abnormalities. By comparison with data from other species, the possible breed association and clinical significance of the observed heteromorphism for the Y chromosome in this species is discussed.

Equine half sibs with an unbalanced X;15 translocation or trisomy 28.

Two unrelated chromosome abnormalities were found in equine half sibs. The proposita, Case 1, which was short in stature and infertile, had a de novo unbalanced X;15 translocation involving loss of Xp. Replication studies indicated that the translocated X was preferentially late replicating and that this late replication spread variably into the autosomal segment. Case 2, a half brother of the proposita, was short in stature, had cryptorchidism, and was trisomic for chromosome 28. Cytogenetic analysis of the dam, the sire of Case 1, and two other phenotypically normal half sibs revealed normal chromosome complements. Five further normal pregnancies were reported. The finding of two unrelated chromosome abnormalities is therefore probably fortuitous in this family. This is the first case of an unbalanced X-autosome translocation and the first case of an autosome trisomy to be reported in the horse.

Familial partial trisomy 15.

A family, including two sibs with partial trisomy 15 is described. Maternal chromosome analysis revealed 46,XX/47,XX,+15q-, mosaicism. These findings are discussed in relation to seventeen previously published cases, some of which were sporadic and others due to maternal balanced translocation.