Utility of severity assessment tools in COVID-19 pneumonia: a multicentre observational study.

BACKGROUND: Severity scores in pneumonia and sepsis are being applied to SARS-CoV-2 infection. We aimed to assess whether these severity scores are accurate predictors of early adverse outcomes in COVID-19. METHODS: We conducted a multicentre observational study of hospitalised SARS-CoV-2 infection. We assessed risk scores (CURB65, qSOFA, Lac-CURB65, MuLBSTA and NEWS2) in relation to admission to intensive care or death within 7 days of admission, defined as early severe adverse events (ESAE). The 4C Mortality Score was also assessed in a sub-cohort of patients. FINDINGS: In 2,387 participants, the overall mortality was 18%. In all scores examined, increasing score was associated with increased risk of ESAE. Area under the curve (AUC) to predict ESAE for CURB65, qSOFA, Lac-CURB65, MuLBSTA and NEWS2 were 0.61, 0.62, 0.59, 0.59 and 0.68, respectively. AUC to predict ESAE was 0.60 with ISARIC 4C Mortality Score. CONCLUSION: None of the scores examined accurately predicted ESAE in SARS-CoV-2 infection. Non-validated scores should not be used to inform clinical decision making in COVID-19.

Paravertebral block with morphine or dexmedetomidine as adjuvant to bupivacaine for post-operative analgesia in modified radical mastectomy: A prospective, randomised, double-blind study.

BACKGROUND AND AIMS: General anaesthesia (GA) is the standard technique and paravertebral block (PVB) is suggested as an ideal analgesic in patients undergoing modified radical mastectomy (MRM). This study assessed post-operative analgesic efficacy of morphine or dexmedetomidine as adjuvant to bupivacaine in PVB. METHODS: Forty-five women (18-60 years) undergoing MRM ± axillary clearance received PVB with 20 ml bupivacaine 0.25% with morphine 3 mg (Group BM) or dexmedetomidine 1 µg/kg (Group BD) in this prospective, randomised, double-blind study. After confirming the onset of PVB, standardised GA induction sequence was used. Intra-operative consumption of fentanyl and propofol along with postoperative morphine and diclofenac consumption, numerical rating scores (NRS) for pain at rest and on movement, nausea and vomiting scores, sedation scores and time to rescue analgesic were recorded. Chi-square or Fisher's exact test and Kruskal-Wallis followed by Mann-Whitney U-test were applied as applicable. RESULTS: The number of patients requiring morphine during first 2-h post-operatively was significantly lower (P = 0.006) in Group BM. The mean dose of morphine in Group BM (0.84 [2.41] mg) and Group BD (1.70 [1.84] mg) was comparable (P = 0.187). NRS for pain at rest and on movement was significantly lower in Group BM at 2, 6, 12 and 18 h. The duration of analgesia was significantly prolonged in Group BM (1019.8 [422.9] min) than in Group BD (263.7 [194.9] min) (P < 0.001). CONCLUSION: Morphine is superior adjuvant to bupivacaine in PVB for modified radical mastectomy than dexmedetomidine.

Solid papillary carcinoma of the nipple: an in situ carcinoma or an expansive growth tumor?

Papillary breast lesions are a heterogeneous group of tumors which mainly arise in the central mammary region, ranging from benign to malignant. Among them, solid papillary carcinoma (SPC) represents a very uncommon variant with indolent clinical behavior and excellent prognosis. The categorization of papillary lesions as benign, atypical or malignant is often difficult even for experienced pathologists. Furthermore, for prognostic purposes, to decide whether to consider a lesions as in situ when it is not associated with frank invasive foci of carcinoma may be problematic. We present a case of solid papillary carcinoma arising in the nipple with an expansive and circumscribed growth, mimicking an in situ lesion of the breast on the hematoxylin and eosin stained sections, but in which a myoepithelial layer around neoplastic nodules could not be detected by using immunohistochemistry. To the best of our knowledge, primary origin in the nipple is very rare for SPCs and it has been described only once in the literature. The case we herein illustrate is of interest not only because of its origin in the nipple, but also because of its not in situ, but invasive, although expansive and not infiltrative growth. In the differential diagnosis, nipple disorders as adenoma and syringomatous adenoma, usual ductal hyperplasia (UDH), papilloma, intracystic papillary carcinoma, lobular carcinoma in situ, ductal carcinoma in situ and skin adnexal tumors are considered.

Prognostic relevance of proliferative activity evaluated by Mib-1 immunostaining in node negative breast cancer.

AIM: The purpose of this prospective observational study was to analyze the role of Mib-1 immunostaining as a proliferation index in breast cancer. Correlations between Mib-1 expression and clinico-pathological characteristics as well as its prognostic value have been studied in a series of 432 node negative breast cancers. METHODS: Mib-1 expression was evaluated by immunohistochemistry. Tumor sections from highly cellular invasive areas of cancer were stained by monoclonal antibody Mib-1 (Dako) and cells whose nuclei stained positive were counted in 10 randomly chosen HPFs and expressed as percentages of all epithelial cells. A minimum of 400 cells were counted. Correlation between Mib-1 staining and clinico-pathological factors was investigated by means of univariate and multivariate analyses. The prognostic impact on actuarial disease free (DFS) and overall survival (OS) was evaluated by univariate analysis using the log-rank test and by multivariate analysis using Cox regression model. RESULTS: Tumors were considered as positive for Mib-1 expression when more than 15% of cells counted were stained. Mib-1 positivity was found in 190/432 cases and resulted in being significantly related to tumor grade, tumor size and absence of estrogen receptors at multivariate analysis. With a median follow-up of 66 months, Mib-1 positivity resulted in being the only independent predictor of OS (RR 2.92), and an independent predictor of DFS (RR 2.01) together with absence of estrogen receptors (RR 2.15). CONCLUSIONS: Mib-1 index of proliferative activity correlates well to other established prognostic factors of breast cancer. Mib-1 index may improve the tailoring of adjuvant therapy in early breast cancer, and our experience adds evidence to its effectiveness as prognostic factor. Efforts to reach uniformity in the methodology and in the scoring system should be done to warrant a standardized procedure and make Mib-1 determination definitively reliable in the current clinical practice.

[Primary squamous cell carcinoma of the breast: a case report]. / Carcinoma squamoso primitivo della mammella: descrizione di un caso.

INTRODUCTION: Primary squamous cell carcinoma (SCC) of the breast is an extremely rare entity and it has a low incidence in comparison with all other mammary cancers. MATERIAL AND METHODS: We describe a case of SCC of the breast in a 55 year old woman who presented with a painless mass located in the external quadrant of the left breast. The neoformation, once removed, was tamponate formalin fixed and routinely processed for inclusion in paraffin. Sections were stained with haematoxilin-eosin and immunohistochemical and electron microscopy investigations were performed. RESULTS: Histologically, the neoplasia was characterized by cystic cavities covered by nests and sheaths of poorly differentiated squamous cells with keratinized areas. Mitotic activity was high, as well as cellular proliferative index, evaluated by Mib-1 (ki 67) antibody. At immunohistochemistry, the tumor cells were diffusely positive for high molecular weight cytokeratins and c-erbB-2, negative for vimentin, estrogen and progesterone. CD68 and LCA were positive only in the inflammatory cells. Electron microscopy confirmed the epithelial nature of the neoplastic cells. A diagnosis of SCC of the breast was made, and a radical mastectomy was performed. CONCLUSIONS: We make a brief review of the literature and discuss the main histologic criteria for the differential diagnosis with adenocarcinoma of the breast with squamous metaplasia.

p53 mutation in breast cancer. Correlation with cell kinetics and cell of origin.

AIM: Several studies have investigated the expression of the cytokeratins (CKs), vimentin, the epithelial growth factor receptor (EGFR), the oestrogen receptor (ER), and the progesterone receptor (PgR), in breast cancer, but no study has directly compared p53 mutations with these phenotypic and differentiation markers in the same case. The present study was designed to provide some of this information. METHODS: The expression of the p53 and bcl-2 proteins was evaluated by immunohistochemistry in relation to phenotypic characteristics and cellular kinetic parameters (mitotic index and apoptotic index) in 37 cases of ductal carcinoma in situ (DCIS) and 27 cases of infiltrating ductal carcinoma (IDC) of the breast. In addition, p53 gene mutation was examined by polymerase chain reaction single strand conformation polymorphism analysis (SSCP). RESULTS: Thirteen cases (eight DCIS and five IDC) showed expression of CK8, CK14, CK18, vimentin, and EGFR, consistent with a stem cell phenotype, whereas 44 cases (27 DCIS and 17 IDC) showed expression of CK8 and CK1, weak or negative expression of CK18, but were negative for vimentin and EGFR, consistent with a luminal cell phenotype. DCIS and IDC cases with a stem cell phenotype were ER/PgR negative and intermediately or poorly differentiated. In contrast, the cases with luminal cell phenotype were ER/PgR positive and well or intermediately differentiated. In addition, intermediately or poorly differentiated cases with a stem cell phenotype showed higher proliferative activity (per cent of MIB-l positive cells) than did intermediately or well differentiated cases with a luminal cell phenotype. Both DCIS and IDC cases with a stem cell phenotype were p53 positive and bcl-2 negative by immunohistochemistry. In IDC, p53 expression was associated with a reduction of both mitotic index and apoptotic index compared with DCIS. Most of the tumours showing a more differentiated phenotype (luminal) were p53 negative and bcl-2 positive. In these cases, cell kinetic parameters increased from DCIS to IDC. These data suggest the existence of subsets of DCIS and IDC that, because of their phenotypic characteristics, could be derived from subpopulations of normal breast cells having different control mechanisms of cell proliferation and neoplastic progression. CONCLUSIONS: These results are compatible with the hypothesis that the phenotype of the cell of origin constrains both tumour phenotype and the choice of genetic events; however, the occurrence of p53 mutants by chance during neoplastic transformation cannot be excluded.

Prediction of lymph node status by analysis of prognostic factors and possible indications for elective axillary dissection in T1 breast cancers.

OBJECTIVE: To identify those patients with T1 breast cancers with lower risk of nodal metastases who can safely be spared axillary dissection. DESIGN: Retrospective study. SETTING: University hospital, Italy. SUBJECTS: Review of clinical records and histopathological slides of 547 patients with T1 breast cancer, operated on between 1984 and 1997. MAIN OUTCOME MEASURES: Incidence of axillary metastases in relation to age, menopausal status, diameter and grade of tumour, vascular invasion, DNA ploidy, S-phase fraction and hormone receptor state, by univariate and multivariate analysis. RESULTS: Axillary metastases were present in 159 patients (29%). On univariate analysis, diameter of tumour 10 mm or less (pT1a/pT1b cancers), no vascular invasion, and grade 1 tumour were significantly correlated with a lower risk of nodal metastases, but only vascular invasion (p = 0.0001, odds ratio = 3.1) and diameter of tumour (p = 0.04, odds ratio = 1.6) were independent predictors on multivariate analysis. Among 34 pT1a/pT1b cancers, with low grade of tumour and no vascular invasion, only 2 (6%) had axillary metastases. When only one favourable predictive factor was associated with diameter of tumour of 10 mm or less, the incidence of axillary metastases ranged from 12% for 43 patients with grade 1 cancers to 13% for 76 patients with no vascular invasion. CONCLUSIONS: Axillary dissection may be avoided in pT1a and pT1b breast cancers (< or = 10 mm), with low grade of tumour or no vascular invasion. T1 breast cancers 10 mm or less in diameter should be treated by a two-step approach, first wide excision of the tumour and then axillary dissection or not depending on pathological examination of the primary tumour.

Lack of association of insulin resistance and carotid intimal medial thickness in non-diabetic Asian Indian subjects.

OBJECTIVE: Atherosclerosis is associated with insulin resistance (IR) and dyslipidaemia. Impaired glucose tolerance (IGT) is characterised by IR and is associated with a higher risk of atherosclerosis. The objective of the present study was to test whether early atherosclerosis indicated by intimal medial thickness (IMT) of common carotid artery (CCA) and internal carotid artery (ICA) is higher in IGT than in normoglycaemic subjects (NGT) and to look for an association of IMT with IR and dyslipidaemia. STUDY DESIGN AND METHODS: Ninety-nine randomly selected non-diabetic subjects aged >or=35 years (48 NGT and 51 IGT) were studied. Measurements of body mass index (BMI), waist/hip ratio (WHR), blood pressure, cholesterol-total, HDL, LDL, VLDL, triglycerides (TG), lipoprotein (a), apolipoprotein-A1 (Apo A1) and apolipoprotein-B (Apo B) and ratio of Apo A1/Apo B were estimated. Insulin resistance (HOMA-IR) was calculated using the fasting plasma insulin and glucose values. IMT of CCA and ICA were measured using high-resolution beta-mode ultrasonography. RESULTS: Subjects with IGT and NGT were matched for BMI and WHR; HOMA-IR was higher in IGT vs NGT (7.92+/-4.2 vs 6.07+/-3.76, p = 0.028). Age-adjusted IMT values were similar in NGT and IGT (CCA 0.59+/-0.17 and 0.63+/-0.22 mm and ICA 0.44+/-0.10 and 0.45+/-0.10 mm, respectively). Further analyses were done in the total group. Multiple linear regression analyses showed that CCA-IMT was significantly associated with age and negatively associated with Apo A1/Apo B ratio. ICA-IMT was associated with age only. IMT was significantly correlated with cholesterol-total and LDL-cholesterol and apolipoproteins. It was not associated with IR. CONCLUSION: In southern Indians, IGT did not influence the IMT. Although insulin resistance was higher in IGT, it was not associated with higher IMT. Conventional risk factors such as cholesterol, LDL-cholesterol and apolipoproteins showed association with IMT in the insulin-resistant population.

Cellular kinetics and expression of bcl-2 and p53 in ductal carcinoma of the breast.

In this study, the expression of p53 (wild-type and mutated form) and bcl-2 in ductal carcinoma in situ (DCIS) and infiltrating ductal carcinoma (IDC) of the breast was evaluated by immunohistochemistry and PCR-SSCP and correlated with cellular kinetic parameters, i.e., mitotic index (MI) and apoptotic index (AI). The results showed a significant inverse correlation between p53 and bcl-2 expression in all cases of DCIS and IDC. In the DCIS group, two subgroups with different kinetic characteristics were identified. The first group was characterized by p53 positivity, bcl-2 negativity and high values of MI and AI; the other group was characterized by p53 negativity, bcl-2 positivity and low values of MI and AI. Conversely, in IDC some cases were p53 negative, bcl-2 positive and with high values of AI and MI, other cases were p53 positive, bcl-2 negative and with low AI and MI. Molecular biological analysis showed that p53 was wild-type in DCIS, while it was in the mutated form in IDC. These results suggest that in IDC mutated p53 contributes to a change in cellular kinetics and the selection of genetically aberrant cells, thereby favouring neoplastic progression. The coexistence of bcl-2 positivity and high AI could be explained by the presence of of apoptosis that work independently of bcl-2.

Expression of p34(cdc2) and cyclins A and B compared to other proliferative features of non-Hodgkin's lymphomas: a multivariate cluster analysis.

In view of recent knowledge on proteins regulating the cell cycle, we re-evaluated proliferative features of 98 diffusely growing non-Hodgkin's lymphomas. The combined use of 5 proliferation-associated variables (mitotic indices and percentages of Ki-67(+), p34(cdc2+), cyclin A(+) and cyclin B(+) cells) and their entry into a multivariate cluster analysis separated, without overlaps, the entire cohort into 3 groups (clusters) with (1) low, (2) intermediate and (3) high proliferative activity. Conversely, bivariate plots exposed considerable cluster overlaps. Multivariate stepwise discriminant analysis of all cases revealed a decreasing order of discriminant power for % Ki-67(+) cells > % p34(cdc2+) cells > mitotic index > % cyclin A(+) cells > % cyclin B(+) cells. The combined use of 2 variables only, mitotic index and % p34(cdc2+) cells, allowed a clear-cut separation of clusters 2 and 3. In bivariate plots, correlations were best between % Ki-67(+) cells and % cyclin A(+) cells and between mitotic indices and % cyclin B(+) cells. Except for chronic lymphocytic leukemias, immunocytomas and marginal zone lymphomas (all in cluster 1), individual lymphoma entities were distributed among at least 2 clusters. There was, however, a marked preponderance of mantle cell lymphomas and diffuse follicular center lymphomas in cluster 1 and of diffuse large B-cell lymphomas and peripheral T-cell lymphomas in cluster 2. Anaplastic large-cell lymphomas predominated in cluster 3 and responded best to therapy.

Expression of the G2-M checkpoint regulators cyclin B1 and P34CDC2 in breast cancer: a correlation with cellular kinetics.

In this study, the expression of cyclin B1 and p34cdc2 in neoplastic and non-neoplastic breast lesions was evaluated by immunohistochemistry and quantitative analysis in relation to cellular kinetic parameters such as Mitotic Index (MI), Anatelophase Index (ATI), and Apoptotic Index (AI). The percentage of cyclin B1 and p34cdc2-positive cells was significantly higher in neoplastic glands than in their normal counterparts. This finding was paralleled by significantly higher values of MI, ATI, and AI in breast cancer than in normal glands. Furthermore, two groups with different cytokinetic characteristics were identified among infiltrating ductal carcinomas by an unsupervised learning technique of cluster analysis using the percentages of cyclin B1 and p34cdc2 positive cells and the cellular kinetic parameters (MI, ATI and AI) as variables. The final clusters, groups I and II, consisted of 42 and 13 cases respectively. The first cluster (group I) was characterized by a significantly linear correlation between the percentages of cyclin B1 and p34cdc2-positive cells. On the contrary, the second cluster (group II) revealed no correlation between these two proteins and was characterized by values of p34cdc2 largely exceeding those of cyclin B1. A positive correlation between the expression of these two proteins and the cellular kinetic parameters (MI, ATI and AI) was also found in group I but not in group II. These observations suggest that a disturbed nuclear translocation of Mitosis Promoting Factor (MPF) components is present in group II cases, resulting in a defective cellular division cycle. In fact, group I cases showed lymph node metastasis more frequently than group II cases. Our results suggest that the analysis of the cell cycle "machinery" components, such as the cyclins and their dependent kinases, can identify tumors with different levels of aggressiveness.

Cell growth and death in malignant lymphomas. A quantitative analysis.

OBJECTIVE: To review the value of biopathologic factors in single lymphomatous patients across the boundaries of histologic classification. STUDY DESIGN: In a series of previous studies, based on a large collection of biopsy samples, the value of the above biopathologic characteristics in individual lymphomatous patients was quantitatively evaluated. RESULTS: The relationships between apoptotic index and growth fraction, in light of the expression of oncogenes, which regulate cell birth and death, were of particular value in determining the growth pattern of different lymphoma cases across the boundaries of histologic classification. CONCLUSION: The study of mechanisms that regulate cell proliferation and death might have therapeutic implications as the proper therapeutic approach should be based on detailed knowledge of the kinetic and molecular characteristics of each tumor.

Retinoblastoma-related p107 and pRb2/p130 proteins in malignant lymphomas: distinct mechanisms of cell growth control.

pRb/p105, p107, and pRb2/p130 compose the retinoblastoma (RB) family of proteins and regulate cellular growth and differentiation. Because recent functional studies have indicated that the expression of the RB-related proteins p107 and pRb2/p130 are tightly cell cycle regulated, we were interested in investigating their expression along with cellular kinetic characteristics and proliferative features of non-Hodgkin's lymphomas (NHLs). p107 and pRb2/ p130 expression was determined immunohistochemically in biopsy specimens from 83 untreated patients with NHLs of various histiotypes. The expression of these two RB-related proteins was correlated with the mitotic index, apoptotic index, and percentages of Ki-67(+), cyclin A(+), p34(+), and cyclin B(+) cells. The overall survival rate was evaluated according to the Kaplan-Meier method and the log-rank test. We found a positive correlation between the percentages of cells positive for p107 and proliferative features such as mitotic index and percentage of Ki-67(+) and cyclin A(+) cells, whereas such correlation could not be demonstrated for the percentages of pRb2/p130 positive cells. Low immunohistochemical levels of pRb2/p130 detected in untreated patients with NHLs of various histiotypes inversely correlated with a large fraction of cells expressing high levels of p107 and proliferation-associated proteins. Such a pattern of protein expression is normally observed in continuously cycling cells. Interestingly, such cases showed the highest survival percentage (82.5%) after the observation period of 10 years. Thus, down-regulation of the RB-related pRb2/p130 protein could be one of the reasons why these cases display such a high rate of proliferation and why they respond so well to therapy.

Expression of laminin 1 and 2 in brain tumor vessels. An immunohistochemical study.

Components of the blood-brain barrier (BBB) include capillary endothelial cells, the vessel basement membrane (BM) and glial cell interface. While endothelial cell peculiarities are well known and thoroughly studied, BM morphology and functional properties are not. Vessel BM throughout the body is composed of laminin 1, the most common variant of laminin, which is made up of alpha 1, beta 1, and gamma 1 laminin chains, while cerebral vessel BM has been reported to also express the alpha 2 chain. In the present study, we show that the BM of newly formed vessels in brain tumors presents the same immunohistochemical structure as normal brain vessel BM, expressing alpha 1, alpha 2, beta 1, and gamma 1 laminin chains. The function of this particular vessel structure in the central nervous system is not yet completely understood; however, we hypothesize that vessel BM could play a role in impeding the extraneural spreading of brain tumors.

Cellular kinetic differences between Hodgkin's and anaplastic large cell lymphomas: relation to the expression of p34cdc2 and cyclin B-1.

Our study was designed to compare cellular kinetic parameters of classical Hodgkin's disease (HD) with those of anaplastic large cell lymphomas (ALCL-C, common type; and ALCL-HL, Hodgkin's like), with a particular focus on the G2/M transition. These disorders share some phenotypic properties, e.g., CD30 positivity of putative neoplastic cells. The percentages of cells expressing p34cdc2 (p34) and cyclin B-1 (cyclin-B), which form a complex (maturation/mitosis promoting factor, MPF) regulating the G2-M phases of the cell cycle, were also registered. Highly significant differences between HD and ALCL-C were recognized: a) in HD, evidence for abortive mitosis (i.e., difficulty to proceed beyond the metaphase stage) and consequent multinucleation and/or deletion of CD30+ cells was prominent, in contrast to ALCL-C. This was associated with a markedly lower fraction of large atypical cells (LAC) expressing cyclin-B in the cytoplasm and the nucleus (C + N) in HD than in ALCL-C; b) the extent of multinucleation of CD30+ cells in HD, but not in ALCL-C, was correlated with the %p34+ LAC; c) the proportions of LAC expressing p34 and/or cyclin-B (C) were positively related to the percentages of cyclin-B (C + N)+ LAC in ALCL-C but not in HD; d) in HD, in contrast to ALCL-C, the size of the fraction of cyclin-B (C + N)+ LAC did not correlate with the ana/telophase indices (ATI, reflecting successful completion of mitosis) and the magnitude of cell loss; e) in ALCL-C, the percentages of p34+ LAC were positively correlated with ATI or the degree of CD30+ cell deletion, but inversely in HD. With regard to all parameters mentioned above, ALCL-HL tended to take an intermediate position between HD and ALCL-C, but sided more with the latter. In conclusion, our present results suggest a derangement of MPF kinetics and functions that is more profound in HD than in ALCL-C.

Growth patterns of diffuse non-Hodgkin's lymphomas estimated from mitotic and apoptotic indices.

Growth rates of neoplasms could be calculated only on the basis of mitotic and apoptotic indices (MI and AI, respectively), assessed on tissue sections, if the duration of mitosis and apoptosis (Tm and Ta, respectively) in vivo were known. For humans, this is practically never the case. What use then can be made of MI and AI to arrive at a relative, crude estimate of the state of growth? As a model system to study this problem, we chose diffusely growing stage I + II non-Hodgkin's lymphomas (dNHL, n = 94). Cluster analysis revealed the existence of 3 highly distinct groups of dNHL (clusters I, II and III) in the MI vs. AI per case plot, with a roughly linear relation between both parameters. Most nosologic entities defined by the REAL classification comprise cases that were represented in more than one cluster. We adopted the simple formula GI (growth index) = XMI - AI, where X (= Ta/Tm) remains to be evaluated. Based on the assumption that spontaneous regressions of dNHL are rare but do occur, we estimated that X = 2 or, possibly, 3 are best fits for the pooled dNHLs studied. With the assumption of X = 2, (i) 2MI - AI gave relatively lower values for dNHL than proliferative indices such as %Ki-67+ cells; (ii) values for 2MI/AI per cluster showed a pattern inverse to that for %bcl-2+ cells; and (iii) a plot of 2MI - AI vs. 2MI/AI per case allowed the recognition, especially among NHLs with a low cell turnover, of cases where accumulation of presumably longer-lived cells is an important factor in determining growth.

Cell kinetics, morphology, and molecular IgVH gene rearrangements in Hodgkin's disease.

The present study dealt with the question of whether any cellular kinetic patterns correlate with clonal rearrangement of the IgVH gene as revealed by polymerase chain reaction on DNA extracted from lymph nodes with classical Hodgkin's disease (HD) and/or from single CD30+ cells (Hodgkin [H] and Reed-Sternberg [RS] cells). In 15/4 cases with H-RS cells of B or Null phenotype, signs of such monoclonality could be detected (group I) but not in the others (group II). CD30+/H-RS cells in group I differed slightly but significantly from those in group II in that they a) exhibited a larger fraction of cells attaining the anaphase/telophase stage of mitosis, and b) produced relatively more mononucleated cells (H) at the expense of multinucleated (RS) cells. In addition, reactive lymphoid cell (CD30-) infiltrates were considerably less dense in group I that in group II. These findings suggest that the cytokinesis of H-RS cells in group I was moderately more efficient than in group II. However, signs of monoclonality were not associated with the normalization of the mitotic process, which also proved to be disturbed in group I.

Cellular kinetic and phenotypic heterogeneity in and among Burkitt's and Burkitt-like lymphomas.

This study asks whether the known genotypic heterogeneity within and between endemic or sporadic Burkitt's lymphomas (eBLs and sBLs, n = 10 each), and Burkitt-like lymphomas (BLLs, n-12), is reflected in divergent cytokinetics and related immunophenotypes. There was strong evidence that eBL and BLL grow markedly faster than sBL, as shown by differences in mitotic and apoptotic indices. Furthermore, in BLL, the median percentage of neoplastic cells immunoreactive for the bcl-2 protein was much higher than that observed in eBL and sBL. The reverse was true for the median fraction of cells containing c-myc protein. In eBL and sBL, the median fraction of bcl-6 protein-positive cells reached values above 50 per cent, while cells of 8/12 BLLs did not contain detectable amounts of this protein. This observation indicates that in this respect, eBL and sBL resemble normal germinal centres of lymphatic tissue much more than do BLL. Evidence for infection of neoplastic cells by the Epstein-Barr virus (EBV) was observed in 9/10 cases of eBL and in 3/10 of sBL, but not in BLL. EBV-positive lymphomas were associated with distinctly lower apoptotic indices and smaller median percentages of bcl-6-positive cells than EBV-negative tumours.

Mitotic activity and nuclear DNA damage of large cells in Hodgkin's disease: comparison with the expression of p53 and bcl-2 proteins and the presence of Epstein-Barr virus.

The roles of the bcl-2 and p53 proteins in Hodgkin's disease (HD) are poorly understood. We therefore compared their detected presence in Hodgkin and Reed-Sternberg/large atypical (H-RS/LA) cells immunohistochemically with the percentages of these cells double-labeled for CD30 and DNA strand breaks (DNA fragmentation index, DFI); mitotic indices (MI); and the EBV infection status. We found a highly significant inverse correlation between the fractions per case of H-RS/LA cells expressing bcl-2/p53 proteins and the DFI of CD30+ elements. No marked effect of these two oncoproteins on MI was noticed, although these parameters and DFI of CD30+ cells were linearly related. EBV infection of H-RS/LA cells exerted only a limited effect on the parameters tested. The results of this study suggest that overexpressed bcl-2 and, to some extent, p53 proteins in H-RS/LA cells of HD primarily counteract deletion of these cells.

Localization of laminin chains in the human retina: possible implications for congenital muscular dystrophy associated with alpha 2-chain of laminin deficiency.

One recently described form of congenital muscular dystrophy (CMD) is associated with deficiency of the alpha 2-chain of laminin, an extracellular matrix protein that is specifically located in the basement membrane of placental villi, Schwann cells and skeletal muscle in healthy humans. This laminin is also normally present in the skin, kidney and basement membrane of blood vessels of the CNS, though it is absent from the blood vessel walls in other tissues. In this immunohistochemical study, we have explored the presence of the alpha 1, alpha 2, beta 1 and gamma 1 chains of laminin in the normal human retina, which are all localized in the basement membrane of blood vessels. This study adds to the growing evidence that the alpha 2-chain of laminin is selectively expressed in certain tissues, and suggests that CMD associated with a lack of this protein may be a multisystem disorder, with possible direct involvement of the visual system.