Summary.We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I-II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases.In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL.Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival.

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with the development of high-grade cervical intraepithelial neoplasia or cancer (CIN3+). However, HPV infection is common and usually transient. Viral load measured at a single time-point is a poor predictor of the natural history of HPV infection. The profile of viral load evolution over time could distinguish HPV infections with carcinogenic potential from infections that regress. A case-cohort natural history study was set-up using a Belgian laboratory database processing more than 100,000 liquid cytology specimens annually. All cytology leftovers were submitted to real-time PCR testing identifying E6/E7 genes of 17 HPV types, with viral load expressed as HPV copies/cell. Samples from untreated women who developed CIN3+ (n = 138) and women with transient HPV infection (n = 601) who contributed at least three viral load measurements were studied. Only single-type HPV infections were selected. The changes in viral load over time were assessed by the linear regression slope for the productive and/or clearing phase of infection in women developing CIN3+ and women with transient infection respectively. Transient HPV infections generated similar increasing (0.21 copies/cell/day) and decreasing (À0.28 copies/cell/day) viral load slopes. In HPV infections leading to CIN3+, the viral load increased almost linearly with a slope of 0.0028 copies/cell/day. Difference in slopes between transient infections and infections leading to CIN3+ was highly significant (P < .0001). Serial type-specific viral load measurements predict the natural history of HPV infections and could be used to triage women in HPV-based cervical cancer screening.Keywords: Viral doubling time virologic model cervical intraepithelial neoplasia liquid-based cytology leftover real-time quantitative PCR

Summary:To evaluate the origin of cells after allogeneic haematopoietic stem cell transplantation we optimised and evaluated two commercially available systems (AmpFlSTR Profiler Plus and GenePrint Powerplex-16) which are based on multiplex fluorescent short tandem repeat (STR) analysis. A standard procedure for interpretation of electropherographs was found essential to obtain reproducible results. On the basis of the relative length of donor and recipient alleles, TYPE-I (no shared alleles are used to calculate chimerism), TYPE-II (one shared and one unshared allele is used to calculate chimerism) or TYPE-III (not informative) allelic distribution types were distinguished. Also, stutter peaks were recognised as an important criterion to exclude a marker for analysis. Intralaboratory and multicentre evaluation of the AmpFlSTR Profiler Plus system showed that mixed blood samples could be determined with an absolute deviation of less than 2%. A sensitivity threshold was set at 5% for TYPE-I and 10% for TYPE-II markers since relative imprecision increases at low chimerism values. No significant difference of calculated chimerism values was observed between STR markers shared between both systems. By monitoring 26 allogeneic peripheral blood stem cell transplants, the applicability of the proposed method was demonstrated. Bone Marrow Transplantation (2001) 28, 511-518.

Trisomy 3 represents the most frequent and consistent chromosomal abnormality characterizing the recently defined entity marginal zone B-cell lymphoma (MZBCL). By cytogenetic analysis and/or fluorescence in situ hybridization (FISH) on interphase nuclei we found in increased copy number of chromosome 3 in 22/36 (61%) successfully analysed cases, including 8/12 cases with extranodal MZBCL, 8/13 cases with nodal MZBCL, and 6/11 patients with splenic MZBCL. Sensitivity of interphase cytogenetics was somewhat higher than that of conventional cytogenetic investigation. Structural chromosomal changes involving at least one chromosome 3 were seen in 11/20 cases with an increased copy number of chromosome 3: +de(3)(p13) was demonstrated in three cases, and was the sole chromosomal abnormality in one of them; +i(3)(q10) was seen in two other patients; and rearrangements involving various breakpoints on the long arm of chromosome 3 were found in the remaining cases. FISH on metaphase spreads confirmed these structural abnormalities and additionally showed two unexpected translocations involving chromosome 3. We conclude that: (1) trisomy 3 occurs in a high proportion of extranodal, nodal and splenic MZBCL; (2) FISH on interphase nuclei is an additional and sensitive tool in detecting an increased copy number of chromosome 3 in MZBCL; (3) additional structural abnormalities involving the long arm of chromosome 3 are frequent but non-recurrent and are perhaps secondary changes; and (4) abnormalities such as +del(3)(pl3) and +i(3)(q10) suggest that genes located on the long arm of chromosome 3 are of particular importance in the pathogenesis of MZBCL.

The incidence of trisomy 12 was studied by conventional chromosome analysis in 111 patients referred as B-cell chronic lymphocytic leukaemia (B-CLL). Fluorescent in situ hybridization (FISH) was also applied in 34 of those patients with either a normal karyotype or no analysable mitoses. By karyotyping, trisomy 12 was present in 11.7% (13/111), whereas additional FISH increased the incidence to 14.4% (16/111). When subdividing our cases in either typical CLL (n = 90), fulfilling the FAB classification criteria, or atypical CLL (n = 21), with one or more variations from those criteria, the incidence of +12 by metaphase analysis was 3% and 48%, respectively. Additional FISH increased the incidence to 4% and 57%. The most common aberration in atypical CLL was FMC7 positivity (n = 11), followed by CD5 negativity (n = 8), strong surface immunoglobulin staining (n = 7) and atypical morphology (n = 6). Trisomy 12 could only be demonstrated in a small proportion of neoplastic cells in all positive cases. By FISH and/or karyotyping, all available samples at diagnosis of the disease were positive.

cTo be acceptable for use in cervical cancer screening, a new assay that detects DNA of high-risk human papillomavirus (hrHPV) types must demonstrate high reproducibility and performance not inferior to that of a clinically validated HPV test. In the present study, a real-time quantitative PCR (qPCR) assay targeting the E6 and E7 genes of hrHPV was compared with Hybrid Capture 2 (hc2) in a Belgian cervical cancer screening setting. In women >30 years old, the sensitivity and specificity for intraepithelial neoplasias of grade 2 or worse (93 cases of cervical intraepithelial neoplasias of grade 2 or worse (CIN2؉) and 1,207 cases of no CIN or CIN1) were 93.6% and 95.6%, respectively, and those of hc2 were 83.9% and 94.5%, respectively {relative sensitivity of qPCR/hc2 ‫؍‬ 1.12 [95% confidence interval (CI), 1.01 to 1.23]; relative specificity ‫؍‬ 1.01 [95% CI, 0.99 to 1.03]}. A score test showed that the sensitivity (P < 0.0001) and specificity (P < 0.0001) of the qPCR assay were not inferior to those of hc2 at the required thresholds of 90% and 98%, respectively. The overall agreement of hrHPV positivity between the two runs of the qPCR tests was 98.7% (95% CI, 97.5 to 99.4%), with a kappa value of 0.96 (95% CI, 0.83 to 1.00). The qPCR assay used in this study can be considered a reliable HPV assay that fulfills the clinical validation criteria defined for use in cervical cancer screening.

No abstract

Subdivision of CLL into typical and atypical subtypes, as proposed by the FAB group in 1989, is not yet widely accepted and its clinical significance is still debated. In recent years, however, a strong correlation was found between atypical morphology trisomy 12 and an aberrant immunophenotype. In the first part of this review we discuss current concepts and generally accepted data on morphology, immunophenotype, genetic abnormalities, clinical features and prognostic factors in CLL. Subsequently, based on our own series and other recently published data, we analyse the validity and clinical impact of classifying CLL into typical and atypical entities and demonstrate that they may represent two closely related but different entities.