Bio-pathological Features Research Articles

Biopathologic Characterization and Grade Assessment of Breast Cancer With 3-D Multiparametric Ultrasound Combining Shear Wave Elastography and Backscatter Tensor Imaging

ObjectiveDespite recent improvements in medical imaging, the final diagnosis and biopathological characterization of breast cancers currently still requires biopsies. Ultrasound is commonly used for clinical examination of breast masses. B-mode and Shear Wave Elastography (SWE) are already widely used to detect suspicious masses and differentiate benign lesions from cancers. But additional ultrasound modalities such as Backscatter Tensor Imaging (BTI) could provide relevant biomarkers related to tissue organization. Here we present a 3D multiparametric ultrasound approach applied to breast carcinomas aiming to (i) validate the ability of BTI to reveal the underlying organization of collagen fibers and (ii) assess the complementarity of SWE and BTI to reveal biopathological features of diagnostic interest. Methods3D SWE and BTI were performed ex vivo on 64 human breast carcinoma samples using a linear ultrasound probe moved by a set of motors. In this paper, we present a 3D multiparametric representation of the breast masses and quantitative measurements combining B-mode, SWE and BTI. ResultsOur results show for the first time that BTI can capture the orientation of the collagen fibers around tumors. BTI was found to be a relevant marker for assessing cancer stages revealing a more tangent tissue orientation for in situ carcinomas than for invasive cancers. In invasive cases, the combination of BTI and SWE parameters allowed for classification of invasive tumors with respect to their grade with an accuracy of 95.7%. ConclusionOur results highlight the potential of 3D multiparametric ultrasound imaging for biopathological characterization of breast tumors.

Global View of Candidate Therapeutic Target Genes in Hormone-Responsive Breast Cancer.

Breast cancer (BC) is a heterogeneous disease characterized by different biopathological features, differential response to therapy and substantial variability in long-term-survival. BC heterogeneity recapitulates genetic and epigenetic alterations affecting transformed cell behavior. The estrogen receptor alpha positive (ERα+) is the most common BC subtype, generally associated with a better prognosis and improved long-term survival, when compared to ERα-tumors. This is mainly due to the efficacy of endocrine therapy, that interfering with estrogen biosynthesis and actions blocks ER-mediated cell proliferation and tumor spread. Acquired resistance to endocrine therapy, however, represents a great challenge in the clinical management of ERα+ BC, causing tumor growth and recurrence irrespective of estrogen blockade. Improving overall survival in such cases requires new and effective anticancer drugs, allowing adjuvant treatments able to overcome resistance to first-line endocrine therapy. To date, several studies focus on the application of loss-of-function genome-wide screenings to identify key (hub) “fitness” genes essential for BC progression and representing candidate drug targets to overcome lack of response, or acquired resistance, to current therapies. Here, we review the biological significance of essential genes and relative functional pathways affected in ERα+ BC, most of which are strictly interconnected with each other and represent potential effective targets for novel molecular therapies.

Clinical, pathological, and molecular data on desmoplastic/nodular medulloblastoma: case studies and a review of the literature.

The aim of this study was to better define the clinical and biopathological features of patients with desmoplastic/nodular medulloblastoma (DNMB) and to further characterize this subgroup. 17 children aged < 5 years, with initial DNMB treated according to the HIT-SKK protocol, were evaluated. A retrospective central radiological review, a pathological and immunohistochemical study, and array-CGH and sequencing of germline SUFU and PTCH1 genes were performed. 15 histologically reviewed cases were confirmed as DNMB including three cases of medulloblastoma with extensive nodularity. Median age at diagnosis was 26 months. Radiology showed five cases with a vermis location and one with T2 hyperintensity. All cases showed a SHH immuno-profile. A 9q deletion was found in 6 cases, a MYCN–MYCL amplification in 1 case, and a SUFU germline mutation in 1 case (/9). The presence of SUFU and PTCH1 germline mutations agreed with previous reports. At 3 years, progression-free survival and overall-survival rates were 72 ± 15% and 85 ± 10%, respectively. The rate of recurrence was relatively high (4 patients). This may have been because chemotherapy was delayed in two cases. Age > 3 years, and residual tumor may also have been an explanation for recurrence.

Urokinase-type plasminogen activator resulting from endometrial carcinogenesis enhances tumor invasion and correlates with poor outcome of endometrial carcinoma patients.

The purpose of this study was to identify the dysregulated genes involved in the tumorigenesis and progression of endometrial endometrioid adenocarcinoma (EEC), and their possible mechanisms. Endometrial specimens including normal endometrial tissues, atypical endometrial hyperplasia, and EEC were analyzed. The expression profiles were compared using GeneChip Array. The gene expression levels were determined by real-time RT-PCR in the training and testing sets to correlate the clinico-pathological parameters of EEC. Immunoblotting, in vitro cell migration and invasion assays were performed in human endometrial cancer cell lines and their transfectants. In microarray analysis, seven dysregulated genes were identified. Only the levels of urokinase-type plasminogen activator (uPA) were higher in EEC with deep myometrial invasion, positive lympho-vascular space invasion, lymph node metastasis, and advanced stages. After multivariate analysis, uPA was the only independent poor prognostic factor for disease-free survival in the EEC patients (hazard ratio: 4.65, p = 0.03). uPA may enhance the migratory and invasive capabilities of endometrial tumor cells by the phosphorylation of ERK1/2, Akt and p38 molecules. uPA is a dysregulated gene involved in the tumorigenesis, bio-pathological features and outcomes of EEC. uPA may be a potential molecule and target for the detection and treatment of EEC.

Biopathologic features and clinical significance of micrometatasis in the lymph node of early gastric cancer.

To evaluate the biopathologic features and clinical significance of nodal micrometastasis (MI) in early gastric cancer (EGC). Among 1022 EGC patients who underwent gastrectomy with lymphadenectomy of D1 + β or more from March 2001 to December 2005 at the Korean National Cancer Center, available nodal metastasis was found in 90 pT1N1 patients. Nodal metastasis was confirmed by immunohistochemistry (IHC) with cytokeratin and patients were classified into MI and macrometastasis (MA) groups based on the main tumor burden according to the 6(th) International Union Against Cancer/American Joint Committee on Cancer staging system; the main tumor burden with a diameter of greater than 0.2 mm but no greater than 2 mm as MI, and greater than 2 mm as MA of the representative metastatic node. Proliferative and apoptotic activities of the primary tumor and the nodal metastasis were measured by IHC with Ki-67 and terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. Biopathologic and clinical features of the patients were analyzed and compared between MI and MA groups. Patients with recurrence were compared with those without recurrence to identify risk factors for recurrence. Thirty-seven patients showed MI and the other 53 patients revealed MA in the lymph node; the incidence of patients with MI and MA was 41.1% and 58.9%. The main tumor burden was 0.9 and 4.6 mm in the representative metastatic node, respectively. Japanese N2 stations were more frequently involved in MA group (20.9%) than in MI group (10.3%) but the difference was not statistically different (P = 0.338). Proliferative and apoptotic activities of MI were decreased than those of MA (26.7% vs 40.5%, P = 0.004 and 1.0% vs 3.0%, P < 0.001, respectively). However, nodal MI in the current study showed a relatively high proliferative activity and an equivalent apoptotic activity compared to other cancers in the previously published studies. Recurrence was observed in 6 patients during the mean follow up period of 87.6 ± 26.2 mo. The recurrence was significantly associated with the presence of MA (P = 0.041) and lymphovascular invasion of the primary tumor (P = 0.032). Lymphadenectomy of D1 + β or more might be necessary in patients with MI in sentinel node to prevent recurrence by clearing MI involving Japanese N2 station.

A systematic analysis of miRNA-mRNA paired variations reveals widespread miRNA misregulation in breast cancer.

MicroRNAs (miRNAs) are a class of small noncoding RNAs that can regulate gene expression by binding to target mRNAs and induce translation repression or RNA degradation. There have been many studies indicating that both miRNAs and mRNAs display aberrant expression in breast cancer. Previously, most researches into the molecular mechanism of breast cancer examined miRNA expression patterns and mRNA expression patterns separately. In this study, we systematically analysed miRNA-mRNA paired variations (MMPVs), which are miRNA-mRNA pairs whose pattern of regulation can vary in association with biopathological features, such as the oestrogen receptor (ER), TP53 and human epidermal growth factor receptor 2 (HER2) genes, survival time, and breast cancer subtypes. We demonstrated that the existence of MMPVs is general and widespread but that there is a general unbalance in the distribution of MMPVs among the different biopathological features. Furthermore, based on studying MMPVs that are related to multiple biopathological features, we propose a potential crosstalk mechanism between ER and HER2.

Abstract P4-07-18: PDGFRbeta-induced miR-9 is up-regulated in triple negative breast cancer

Abstract miR-9 has been described as an oncogenic microRNA associated to a metastatic phenotype and able to induce EMT (epithelial-to-mesenchymal transition) through direct targeting of E-cadherin. However, data available concerning the expression and the role of this microRNA in different subgroups of breast cancer are still not exhaustive. Evaluating miR-9 expression by Real-Time PCR in a series of 92 breast cancer specimens (35 luminal, 36 HER2, 21 triple negative), we found that this microRNA is increasingly higher in HER2 and Triple Negative versus ER positive patients (fold change 3 and 8 respectively). Moreover, preliminary analysis of miR-9 expression in correlation with bio-pathological features and clinical data also indicates a trend in association with disease progression. Triple Negative Breast Cancers represent a very aggressive breast cancer subgroup, still lacking specific markers for an effective targeted therapy; we investigated whether miR-9 might play a role in the biology of this tumor subtype. Preliminary data indicate that miR-9 is activated downstream PDGFRbeta, which represents a crucial player in the aggressive phenotype of Triple Negative Breast Cancer. In summary, here we show that miR-9 is significantly upregulated in triple negative breast cancer in comparison with other breast cancer subgroups and is activated downstream PDGFRbeta. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-07-18.

Overexpression of miR-92a correlates with tumor metastasis and poor prognosis in patients with colorectal cancer

MicroRNAs regulate gene expression at the post-transcriptional level and play important roles in cancer development, progression, and metastasis. The aim of this study was to investigate the expression of miR-92a in colorectal cancer and the normal adjacent mucosa and its potential relevance to clinicopathological characteristics and patient survival. Surgical specimens of cancer tissue and adjacent normal mucosa were obtained from 82 patients with colorectal carcinomas. The relative expression levels of miR-92a mRNA in the cancer and the normal adjacent mucosa were measured by quantitative real-time reverse transcriptase polymerase chain reaction. We analyzed their correlation with tumor metastasis, clinicopathologic parameters, and clinical outcome. The relative expression levels of miR-92a were significantly higher in colorectal cancer tissues than in the normal adjacent mucosa (p < 0.001), and a high expression of miR-92a correlated with advanced clinical stage (p = 0.025), lymph node metastases (p = 0.015), and distant metastases (p = 0.046). Kaplan-Meier analysis indicated that patients with high miR-92a expression had a poor overall survival (p = 0.001). Moreover, multivariate analysis showed that increased expression of miR-92a was an independent predictor of overall survival. This study revealed that miR-92a overexpression was correlated with specific colorectal cancer biopathologic features, such as TNM stage, lymph node and distant metastases, and poor survival of the patients, indicating that miR-92a may serve as a molecular prognostic marker for colorectal cancer and disease progression.

Atypical primary meningioma in the nasal septum with malignant transformation and distant metastasis

BackgroundPrimary extracranial meningiomas (PEMs) originating from the nasal septum are extremely rare, as are extracranial metastases of meningiomas.Case presentationA 44-year-old male presented with a 2-month history of left-side nasal obstruction and frequent episodes of epistaxis. A friable mass originating from the nasal septum was resected completely via an endoscopic endonasal approach. According to WHO criteria, the tumor was diagnosed as an atypical meningioma radiologically and histopathologically. Two years later, a tumor recurred at the primary site with the same histopathological findings, and the patient was given local external radiotherapy (6840 cGy in 38 fractions). Two months after this local recurrence, a left anterior chest wall mass and a left parietal area scalp mass were observed. The subcutaneous mass was resected and showed histological evidence of malignant transformation. Several months after the last operation, the patient died.ConclusionsWe describe the clinical, radiological, and bio-pathological features of this unique case and review the literature on atypical PEMs originating in the nasal septum. To our knowledge, this is the first reported case of an atypical PEM originating from the nasal septum that recurred with malignant transformation and extracranial metastasis.

Low-grade extraskeletal osteosarcoma of the chest wall: case report and review of literature

BackgroundLow-grade extraskeletal osteosarcomas (ESOS) are extremely rare.Case presentationWe present the first case of low-grade ESOS of the chest wall, which occurred in a 30-year-old man. Because of initial misdiagnosis and patient's refusal of surgery, the diagnosis was done after a 4-year history of a slowly growing mass in soft tissues, leading to a huge (30-cm diameter) calcified mass locally extended over the left chest wall. Final diagnosis was helped by molecular analysis of MDM2 and CDK4 oncogenes. Unfortunately, at this time, no surgical treatment was possible due to loco-regional extension, and despite chemotherapy, the patient died one year after diagnosis, five years after the first symptoms.ConclusionWe describe the clinical, radiological and bio-pathological features of this unique case, and review the literature concerning low-grade ESOS. Our case highlights the diagnostic difficulties for such very rare tumours and the interest of molecular analysis in ambiguous cases.

Biopathological characteristics of hilar cholangiocarcinoma and the clinical significance

To approach the biopathological features of hilar cholangiocarcinoma and surgical pathological factors which influence the long-term survivals of patients with hilar cholangiocarcinoma. A systemic and retrospective multi-parameter analysis was performed on 205 patients of hilar cholangiocarcinoma who received surgical treatments and had complete clinicopathological data as well as follow-up results during a ten-year-period from April 1998 to April 2008. The single factor analysis was performed on age, sex, content of pre-operative serum CA19-9, Child-pugh grading, TNM classification, operation pattern, resection margin status of bile duct, vascular invasion, adjacent liver involvement, grade differentiation, infiltration-depth of bile duct, lymph node metastasis and perineural infiltration. A multivariate analysis was performed through Cox proportional hazard model. The single factor analysis showed that except age, sex and content of pre-operative serum CA19-9, the mainly significant factors influencing the survivals were Child-Pugh grading, TNM classification, operation pattern, bile duct margin, vascular invasion, adjacent liver involvement, grade differentiation, infiltrating-depth of bile duct, lymph node metastasis and perineural infiltration (P < 0.05). Lymph node metastasis and infiltration-depth of bile duct wall were found to be the two independent factors influencing overall survival by multivariate analysis through the Cox model. The most important prognostic factors influencing the long-term survivals of patients with hilar cholangiocarcinoma after operation are lymph node metastasis and depth of tumor-infiltrating of involved bile duct. During the operation, standardized evaluation through frozen section should be carried out for detection of lymph node metastasis and depth of tumor-infiltrating of involved bile ducts, which can be used as the histological indicator for surgical expansion, and could be helpful to maximize avoiding the tumor cell residues and therefore, to improve the long-term effects of surgical resection.

MicroRNA miR-21 overexpression in human breast cancer is associated with advanced clinical stage, lymph node metastasis and patient poor prognosis

To investigate the global expression profile of miRNAs in primary breast cancer (BC) and normal adjacent tumor tissues (NATs) and its potential relevance to clinicopathological characteristics and patient survival, the genome-wide expression profiling of miRNAs in BC was investigated using a microarray containing 435 mature human miRNA oligonucleotide probes. Nine miRNAs of hsa-miR-21, hsa-miR-365, hsa-miR-181b, hsa-let-7f, hsa-miR-155, hsa-miR-29b, hsa-miR-181d, hsa-miR-98, and hsa-miR-29c were observed to be up-regulated greater than twofold in BC compared with NAT, whereas seven miRNAs of hsa-miR-497, hsa-miR-31, hsa-miR-355, hsa-miR-320, rno-mir-140, hsa-miR-127 and hsa-miR-30a-3p were observed to be down-regulated greater than twofold. The most significantly up-regulated miRNAs, hsa-mir-21 (miR-21), was quantitatively analyzed by TaqMan real-time PCR in 113 BC tumors. Interestingly, among the 113 BC cases, high level expression of miR-21 was significantly correlated with advanced clinical stage (P = 0.006, Fisher's exact text), lymph node metastasis (P = 0.007, Fisher's exact text), and shortened survival of the patients (hazard ratio [HR]=5.476, P < 0.001). Multivariate Cox regression analysis revealed this prognostic impact (HR=4.133, P = 0.001) to be independent of disease stage (HR=2.226, P = 0.013) and histological grade (HR=3.681, P = 0.033). This study could identify the differentiated miRNAs expression profile in BC and reveal that miR-21 overexpression was correlated with specific breast cancer biopathologic features, such as advanced tumor stage, lymph node metastasis, and poor survival of the patients, indicating that miR-21 may serve as a molecular prognostic marker for BC and disease progression.

ErbB/HER ligands in human breast cancer, and relationships with their receptors, the bio-pathological features and prognosis

BackgroundThe aim of this study is to provide an expression profile of ErbB/HER ligands in breast cancer. We analysed the relationships with their receptors, the bio-pathological features and prognosis. Patients and methodsEpidermal growth factor (EGF), transforming growth factor-α (TGFα), amphiregulin (AREG), betacellulin (BTC), heparin-binding EGF-like growth factor (HB-EGF), epiregulin (EREG) and neuregulins1–4 (NRG1–4) were quantified in 363 tumours by real-time reverse transcription–polymerase chain reaction using TaqMan probes. ResultsLigands were detected in 80%–96% of the cases, except NRG3 (42%) and EREG (45.5%). At least one ligand was expressed in 304 cases (cut-off: upper quartile). Almost all combinations of receptor and ligand co-expressions were observed, but TGFα is preferentially expressed in tumours co-expressing EGFR/HER3, NRG3 in those co-expressing EGFR/HER4, AREG and EREG in those co-expressing HER2/HER4. EGF and AREG were associated with estradiol receptors, small tumour size, low histoprognostic grading, high HER4 levels. TGFα, HB-EGF and NRG2 were negatively related to these parameters. In Cox univariate analyses, EGF was a prognostic factor. ConclusionOur study demonstrates that (i) ErbB/HER ligands, including BTC and EREG, are expressed in most breast cancers; and (ii) TGFα, HB-EGF and NRG2 high expressions are related to the biological aggressiveness of the tumours.

MicroRNA Signatures in Human Ovarian Cancer

Epithelial ovarian cancer (EOC) is the sixth most common cancer in women worldwide and, despite advances in detection and therapies, it still represents the most lethal gynecologic malignancy in the industrialized countries. Unfortunately, still relatively little is known about the molecular events that lead to the development of this highly aggressive disease. The relatively recent discovery of microRNAs (miRNA), a class of small noncoding RNAs targeting multiple mRNAs and triggering translation repression and/or RNA degradation, has revealed the existence of a new level of gene expression regulation. Multiple studies involving various types of human cancers proved that miRNAs have a causal role in tumorigenesis. Here we show that, in comparison to normal ovary, miRNAs are aberrantly expressed in human ovarian cancer. The overall miRNA expression could clearly separate normal versus cancer tissues. The most significantly overexpressed miRNAs were miR-200a, miR-141, miR-200c, and miR-200b, whereas miR-199a, miR-140, miR-145, and miR-125b1 were among the most down-modulated miRNAs. We could also identify miRNAs whose expression was correlated with specific ovarian cancer biopathologic features, such as histotype, lymphovascular and organ invasion, and involvement of ovarian surface. Moreover, the levels of miR-21, miR-203, and miR-205, up-modulated in ovarian carcinomas compared with normal tissues, were significantly increased after 5-aza-2'-deoxycytidine demethylating treatment of OVCAR3 cells, suggesting that the DNA hypomethylation could be the mechanism responsible for their overexpression. Our results indicate that miRNAs might play a role in the pathogenesis of human EOC and identify altered miRNA gene methylation as a possible epigenetic mechanism involved in their aberrant expression.

Alterations of Biological Features of the Cerebellum in Sudden Perinatal and Infant Death

This article intends to show how the cerebellum, a structure ordinarily not considered in mediating breathing or cardiovascular control, may play a critical role in compensatory responses particularly to hypoxic insults occurring pre and/or postnatally and thus may be involved in the sudden unexplained perinatal and infant death. Besides the ontogenesis of the cerebellar cortex in man, we reported alterations of biopathological features (neuronal immaturity, altered apoptotic programs, negative expression of somatostatin and EN2 gene, intense c-fos expression positivity, astrogliosis) in the cortex and in the dentate nucleus of the 63% of sudden deaths, and only in 10% of the controls. The correlation of these results with the mother's smoking habit was highly significant. Therefore, we support the hypothesis, already expressed in previous studies on brainstem, of a close relation between maternal cigarette smoking and a wide range of morpho-physiological defects of the brain, leading to unexplained sudden death in stillbirths, newborns, and Sudden Infant Death Syndrome (SIDS) victims.

MicroRNA Gene Expression Deregulation in Human Breast Cancer

MicroRNAs (miRNAs) are a class of small noncoding RNAs that control gene expression by targeting mRNAs and triggering either translation repression or RNA degradation. Their aberrant expression may be involved in human diseases, including cancer. Indeed, miRNA aberrant expression has been previously found in human chronic lymphocytic leukemias, where miRNA signatures were associated with specific clinicobiological features. Here, we show that, compared with normal breast tissue, miRNAs are also aberrantly expressed in human breast cancer. The overall miRNA expression could clearly separate normal versus cancer tissues, with the most significantly deregulated miRNAs being mir-125b, mir-145, mir-21, and mir-155. Results were confirmed by microarray and Northern blot analyses. We could identify miRNAs whose expression was correlated with specific breast cancer biopathologic features, such as estrogen and progesterone receptor expression, tumor stage, vascular invasion, or proliferation index.

Simultaneous chromosome 1q gain and 16q loss is associated with steroid receptor presence and low proliferation in breast carcinoma

We applied comparative genomic hybridization (CGH) to 46 breast carcinoma samples, collected from 1993 to 1995, in order to detect chromosome 1q gains and 16q losses and to define whether samples showing both these alterations had distinct biopathologic features and different clinical outcome. A total of 22 samples (48%) had simultaneous chromosome 1q gain and 16q loss, which was always associated with other genetic changes. In total, 23 samples had various chromosome imbalances (including chromosome 1q gain independent of chromosome 16q loss and vice versa) and one sample did not show detectable alterations. Samples having chromosome 1q gain/16q loss were compared to the other samples with regard to neoplasm size, lymph-node status, histologic and nuclear grade, estrogen and progesterone receptor presence, Ki-67, pRB, Cyclin D1, Cyclin A, p53, p21 and p27 expression as detected by immunohistochemistry. The samples showing chromosome 1q gain/16q loss had high steroid hormone receptor expression (P=0.02), low cell growth fraction (Ki-67, P=0.03) and high p27 expression (P<0.001). No statistical correlation with disease-free survival and overall survival or response to hormonal therapy was found. We conclude that simultaneous chromosome 1q gain/16q loss is a frequent event in invasive breast cancer, which occurs in a subset of both intermediate- and high-grade breast carcinomas. Although the final chromosome 1q and 16q imbalances might have originated from different chromosome alterations in low- and high-grade samples, the gene–dosage effect might be important in conferring peculiar biopathologic characteristics to this subset of samples. The cytogenetic and molecular mechanisms underlying these chromosome changes deserve further investigations.

BRCA1 mutations and clinicopathological features in a sample of Italian women with early-onset breast cancer

Breast cancer in young women is uncommon and often presents with unfavourable biopathological features. Although early age at onset could suggest a genetic susceptibility to cancer, the appropriateness of BRCA1 testing for women with early-onset breast cancer and modest family history (FH) is controversial. 40 Women diagnosed with breast cancer at the age of 35 years or less, unselected for FH, were screened for germ line BRCA1 mutations by automated sequencing of exons 2, 5, 6, 11, 13 and 20. Overall, deleterious mutations were evidenced in 6 (15%) patients. With regard to FH, mutations were detected in 14%, 11% and 29% of women with none, weak and strong FH, respectively. Large tumour size, grade 3, lack of oestrogen receptors and high proliferation rate were significantly more common in mutation carriers (MC). Our data support both the appropriateness of testing young breast cancer patients and the frequency of unfavourable features in BRCA1-related breast cancer. It is hypothesised that BRCA1 mutations partially justify the high rate of aggressive breast cancer in young patients and that combining age and breast cancer phenotype could help to identify probable MC.

Biopathologic features of Hodgkin's disease.

The neoplastic nature of Hodgkin's disease (HD) is suggested by several lines of evidence, including aggressive clinical course, presence of proliferating atypical cells morphologically recognized as Hodgkin's and Reed-Sternberg cells (H-RS), aneuploidy, and, in the minority of cases, clonality. Nevertheless, the etiopathogenesis of HD still remains elusive, and probably diverse. This uncertainty is partly due to the peculiar histology of HD lesions, characterised by the paucity of the putative neoplastic cell component, i.e. H-RS cells, admixed to a variety of reactive cells which prevent an exhaustive investigation at molecular level. Nevertheless, the possible involvement of different molecules with oncogenic potential has been recently suggested on the basis of immunohistological and molecular biology studies. These include oncogenes such as bcl-2 and MDM2 and anti-oncogenes such as p53. In addition, a large amount of data has accumulated on the possible role of EBV infection in HD. The colonization of lymphoid tissues by immortalized H-RS cells can account for the derangement of cytokine networks leading to microenvironmental and systemic abnormalities. In addition, a variety of soluble receptors (sIL-2R, sCD30, sTNF-R), and adhesion molecules (sICAM-1) are abnormally produced at sites of disease involvement. Some of these molecules still retain the ability to bind their ligands and can potentially contribute to the derangement of immune mechanisms observed in HD. Many of these soluble molecules can also be found in the patient's sera providing new potential prognostic and follow-up parameters in HD patients. The comparative analysis of the same molecules within the tissue, using immunohistochemistry, and in the blood, using immunochemical assays, appears as a promising informative approach.