Nabothian cyst content: A potential pitfall for the diagnosis of invasive cancer on Pap test cytology

Nabothian cysts are common, benign findings of the squamocolumnar junction of the adult cervix. These cysts are filled with mucus and can also contain proteinaceous material, neutrophils, or neutrophil debris. Nabothian cysts can be broken by the spatula during smear taking, may stick to the brush and be smeared onto slides in conventional cytology or dissolved in the preserving solution for liquid-based cytology (LBC) preparations. The granular content of Nabothian cysts may be mistaken for the tumor diathesis (TD) pattern associated with invasive carcinoma. In the case described, the patient presented a high-grade squamous intraepithelial lesion associated with granular material (Nabothian cyst content) that we considered erroneously on LBC to be TD-like material, thus, raising the suspicion of invasive carcinoma. To the best of our knowledge, this is the first report showing that Nabothian cyst content may present a potential pitfall in the diagnosis of invasive carcinoma on LBC.

FNA diagnosis of poorly differentiated thyroid carcinoma. A review of the recent literature

Poorly differentiated thyroid carcinoma (PDTC) is a follicular cell-derived tumour that was recognised as a distinct entity by the World Health Organisation in 2004. The natural history and pathological features of PDTC are reported to be intermediate between those of well-differentiated and undifferentiated (anaplastic) thyroid carcinomas. Preoperative identification of PDTC could facilitate better initial patient management in many cases, namely more extensive surgery, without any delay. However, according to some experts, a diagnosis of PDTC can only be rendered on histologic specimens based on criteria recommended in the Turin proposal. Although high-grade features (namely necrosis and mitoses) can be recognised in FNA material, other cytomorphological features have limited value for the preoperative diagnosis of PDTC and specific features for a definitive diagnosis of PDTC have not yet been clearly defined. Here, we review the current status and future prospects for cytological recognition of PDTC; we emphasise the features that should raise suspicion of this rare condition in FNA cytology and provide an update on molecular features and management of PDTC. Despite proposed histological criteria for the diagnosis of PDTC, its recognition on routine thyroid cytology presents a notable challenge. Current and future advances in molecular testing could contribute to the cytological diagnosis of PDTC.

Methylation of miR124a-1, miR124a-2, and miR124a-3 in Hodgkin lymphoma

Deregulation of the microRNA miR124a by DNA methylation has been implicated in various malignancies, but no study reported its methylation status in Hodgkin lymphoma (HL). We evaluated the methylation of the three loci encoding for miR124a using methylation-specific PCR in 64 HL patients and 15 reactive lymph nodes obtained from patients with nonmalignant diseases. Results were correlated with clinicopathological parameters. Methylation rates of miR124a-1, miR124a-2, and miR124a-3 in HL were 17, 50, and 28%, respectively. None of the nontumoral samples showed aberrant hypermethylation in any of the miR tested. In HL cases, we found that miR124a-1 methylation correlates with high-risk International Prognostic Score (IPS) (score >3, p = 0.04) and that miR124a-2 methylation was more frequent in children (82.3%, p = 0.006) and men (63.9%, p = 0.01). Methylation of miR124a-3 was associated with advanced Ann-Arbor stages (p = 0.007). The survival analysis showed that methylation of at least one of the miR124a genes was associated with shortened event-free survival in univariate (p = 0.03) and multivariate (p = 0.02) analyses. These results suggest that miR124a methylation is associated with aggressive HL disease and may be an interesting factor for predicting treatment response.

Metastasizing pleomorphic adenoma of the submandibular gland: a case report

Pleomorphic adenoma (PA), originally called mixed tumour, is the most common neoplasm of the salivary glands. It is usually a benign, slow-growing and well-circumscribed tumour. However, PA may occasionally give rise to metastases that usually occur after a previous recurrence. These tumours display benign histological features in both primary tumours and metastases. Such tumours have been termed metastatic PA or metastatic mixed tumours. We report a case of metastatic PA of the submandibular gland with metastasis to the cervical lymph nodes.

Correlation between DNA methyltransferases expression and Epstein-Barr virus, JC polyomavirus and Helicobacter pylori infections in gastric carcinomas

It' is accepted that aberrant expression of DNA methyltransferases (DNMTs) is responsible for hypermethylation in genes. However, there are limited data related to factors inducing aberrant expression of DNMTs. A total of 43 surgically resected gastrc carcinomas (GC) samples were analysed. Using immunohistochemistry assay we have determined expression level of DNMT1 and 3b. The presence of H.pylori was evaluated by histology, whereas JC polyomavirus (JCV) and Epstein-Barr virus (EBV) detection were carried out by PCR and in situ hybridization techniques, respectively. High expression of DNMT1 and 3b were detected in 46.5% and 53.5% of GC cases, respectively. Co-expression of DNMT1 and 3b were found in 37.2% of cases. Using different techniques, H. pylori, JCV and EBV were detected in 55.8%, 32.6% and 9%, respectively. Moreover, in 37% of cases, we noted the presence of JCV and/or EBV infections. H.pylori co-infection was found in 64.3% (9/14) of JCV positive cases and in 50% of EBV positive GC, without a reliable significant relationship. Correlation analyses have showed a marked increase in DNMT1 expression in EBV associated GC (P= 0.02). Also, co-expression of DNMT1 and 3b was significantly associated with EBV infection in GC (P=0.05). Similarly, JCV associated GC mostly displayed DNMT1 positive status, but the difference did not reach the significant threshold. Nevertheless, infection with JCV and/or EBV was significantly correlated with increased expression of DNMT1 in GC (P= 0.05). Our study suggests that EBV and JCV infections in GC correlated with deregulation of DNA methyltransferases.

Patterns of aberrant DNA hypermethylation in nasopharyngeal carcinoma in Tunisian patients

BACKGROUND

Aberrant methylation in the promoter of tumor-related genes is associated closely with epigenetically mediated gene silencing. The aim of the present study was to evaluate the methylation profile of Tunisian nasopharyngeal carcinoma (NPC) and to determine the clinicopathological features of tumors showing this epigenetic alteration.

METHODS

Thirty-six archival NPC biopsies were investigated in comparison with 19 non-tumor nasopharyngeal tissue specimens. DNA methylation status of ten tumor-suppressor and related genes was analyzed by using methylation-specific PCR. The Epstein-Barr virus (EBV) presence was verified by PCR and in situ hybridization and the LMP1 oncoprotein expression was analyzed by immunohistochemistry. Findings were then correlated with clinicopathological variables (Patients' gender and age, tumor histological subtype and stage).

RESULTS

Hypermethylation frequencies of the investigated genes in NPC biopsies were 75% for RASSFIA, 58.3% for SHP1, 47.2% for DAPK, 33.3% for P16, 31% for RARβ2, 19.4% for GSTP1 and TIMP3, 11% for APC and CDH1, and 5.5% for MGMT. In non-tumor nasopharyngeal samples, hypermethylation was detected in lower frequencies in 6 genes (SHP 26.3%, P16 21%, RARβ2 21%, DAPK 15.8%, TIMP3 10.5%, and GSTP 5.3%). Hypermethylation of RARβ2 promoter was more frequent in tumors with lymph node metastasis than those without metastasis (43.5% vs 0%, p=0.03). Methylation of RASSF1A was more frequently detected in non-keratinizing NPC than in undifferentiated subtype (100% vs 66.7%; p=0.05). A trend toward positive association was found between an increased number of methylated genes and LMP1 expression (p=0.07). However, no significant association was found for the remaining variables.

CONCLUSIONS

This study indicates that hypermethylation of multiple genes is a common alteration in nasopharyngeal carcinomas in Tunisian patients and that this epigenetic change may play a role in the nasopharyngeal carcinogenesis.

[Eighteen cases of craniofacial fibrous dysplasia]

INTRODUCTION

Fibrous dysplasia or Jaffe Lischtenstein's disease is sporadic and rare bone affection, mainly observed in young adults. It is characterized by a bone maturation disorder that can affect one or several bones. Fibrous dysplasia is relatively rare in the craniofacial region, (only 20% of all locations). The authors analyzed the epidemiological, anatomoclinical and evolutive features of fibrous dysplasia in a Tunisian population.

MATERIAL AND METHOD

The authors retrospectively studied 18 cases of craniofacial fibrous dysplasia, diagnosed at the pathology department of the Sousse F. Hached hospital, beween1990 and 2005.

RESULTS

Most craniofacial dysplasia cases were monostotic (94% of cases). One case was polyostotic. The maxilla and the mandible were the most frequent locations (83.3%). The patients' mean age was 28.6 years, ranging from 6 to 30 years. The sex ratio was 3.5 in favor of women. Follow-up ranged from one month to 10 years with an average of 26.4 months. One case of sarcomatous transformation was observed.

DISCUSSION

The authors noted epidemiological discrepancies compared to what was usually reported, especially concerning the strong female predominance, the frequency of maxillary and mandibular locations and the predominance of monostotic presentations. Larger series are needed to validate these observations.

Evidence for a role of the Simian Virus 40 in human breast carcinomas

AIMS OF THE STUDY

The aim of this study was to investigate whether the Simian Virus 40 (SV40) is implicated in human breast carcinomas (BC).

EXPERIMENTAL DESIGN

SV40 presence was investigated by PCR assays targeting the Tag, the regulatory, and the VP1 regions in 109 invasive breast ductal carcinomas from Tunisian women. We also examined the relationship between the presence of SV40 and promoter methylation status of 15 tumor-related genes. Immunohistochemistry was used to investigate the expression of Tag, estrogen and progesterone receptors, HER2, and P53.

RESULTS

SV40 DNA sequences were detected in 22% of tumors and in only 1.8% of the matched non-tumoral tissues. Using immunohistochemistry, SV40 was detected in the tumor cells. Hypermethylation frequencies were 78% for RASSF1A, 66% for SHP1, 61% for HIN1 and BRCA1, 47% for P16 and ER, 42% for CDH1 and APC, 40% for BLU, 35% for DAPK, 34% for RARbeta2, 27% for GSTP1, 17% for TIMP3, 14% for CCND2, and 8% for hMLH1. Interestingly, the frequencies of RASSF1A, SHP1, BRCA1, and TIMP3 methylation, and the mean of the methylation index (MI) were significantly higher in SV40-positive than in SV40-negative cases (P-values ranging from 0.043 to 0.003). Moreover, SV40 presence correlates with P53 protein accumulation (32.7% vs. 13.3%; P=0.015) and HER2 low expression (3.7% vs. 28%; P=0.008). We also found SV40 more frequently in patients over 50 years than in younger patients (34.8% vs. 12.3%; P=0.006).

CONCLUSIONS

This study is the first to demonstrate the presence of SV40 in human BC and provides data supporting a role for this virus in the pathogenesis of these tumors.

Prevalence and characteristics of the MMTV-like associated breast carcinomas in Tunisia

The involvement of a retrovirus homologous to the mouse mammary tumor virus (MMTV) in the pathogenesis of human breast cancer (BC) has long been assumed, but has never been proven. Previous studies have reported the detection of MMTV-like env sequences in variable proportions that did not exceed 40% of BC cases in several countries. However, these viral sequences have been found in higher proportion (74%) in Tunisian diagnosed with BC during the seventies. This study is an attempt to evaluate the current prevalence of MMTV-like env gene in BC in Tunisian women. We used semi-nested PCR that amplify a 190-bp MMTV-like env sequence, followed by direct sequencing to screen a series of 122 cases of BC randomly selected. The findings were correlated to clinicopathological data and immunohistochemical expression status of progesterone and oestrogen receptors, HER2, and P53. Specific MMTV-like env sequences were found in 17 (13.9%) cases of breast carcinomas, whereas the same sequences were not detected in matched normal breast tissues. The presence of the viral sequences correlates inversely with progesterone receptor expression (6.8% versus 20.3%; P=0.03) and HER2 overexpression (3.1% versus 17.7%; P=0.04). This present study confirms the presence of MMTV-like env sequences in BC in Tunisian women but describes an important decrease in the prevalence of the viral sequences compared with previous studies. This reduction may be due to some changes in the virological characteristics or exposure to the virus.

Prognostic significance of aberrant promoter hypermethylation of CpG islands in patients with diffuse large B-cell lymphomas

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) exhibits heterogeneous clinical features and a marked variable response to treatment.

PATIENTS AND METHODS

We investigated the prognostic significance of the methylation status of DAPK, GSTP1, P14, P15, P16, P33, RB1, SHP1, CDH1, APC, BLU, VHL, TIMP3, and RASSF1A genes in 46 DLBCL specimens from Tunisian patients. Methylation status of each gene was correlated with clinicopathological parameters including the International Prognostic Index (IPI), the germinal center immunophenotype, and response to treatment and survival. Overall survival (OS) and disease-free survival (DFS) rates were calculated by the Kaplan-Meier method and differences were compared with the log-rank test.

RESULTS

Hypermethylation of SHP1 was associated with elevated lactate dehydrogenase level (P = 0.031). P16 and VHL were frequently hypermethylated in patients with high IPI scores (P = 0.006 and 0.004) and a performance status of two or more (P = 0.007 and 0.047). In addition, hypermethylation of P16 was significantly associated with advanced clinical stages and B symptoms (P = 0.041 and 0.012). Interestingly, hypermethylation of DAPK was significantly correlated with resistance to treatment (P = 0.023). With regard to survival rates, promoter hypermethylation of DAPK, P16, and VHL were significantly associated with shortened OS (P = 0.003, 0.001, and 0.017, respectively) and DFS (P = 0.006, 0.003, and 0.046, respectively). In multivariate analysis, hypermethylation of DAPK remains an independent prognostic factor in predicting shortened OS (P = 0.001) and DFS (P = 0.024), as well as the IPI and the germinal center status.

CONCLUSIONS

This study demonstrates that DLBCLs with hypermethylated P16, VHL, DAPK, and SHP1 commonly show a biologically aggressive phenotype and worse prognosis. Interestingly, hypermethylation of DAPK was found to be an independent prognostic factor that may be used in conjunction with the conventional prognostic factors such as the IPI and the germinal center status.

Granuloma multiforme: first case report in Tunisia

Granuloma multiforme is a rare granulomatous skin disease, usually reported in sub-Saharan African countries. The exact aetiology of granuloma multiforme is still unknown. We report the case of a patient who presented clinical and histopathological features of granuloma multiforme that can be considered the first described case in Tunisia.

[Human subconjunctival dirofilariasis: two Tunisian case studies]

Two new cases of human subconjunctival dirofilariasis are reported in Tunisia. Dirofilaria immitis was identified in the first case and Dirofilaria repens in the second. Diagnosis was made by histological examination of excised nodules. We note that the patients are young (8 and 10 years, respectively) and that cases of human dirofilariasis caused by Dirofilaria immitis are present in Tunisia.

[Salivary duct carcinoma]

INTRODUCTION

Salivary duct carcinoma is a very rare tumor of the salivary glands that has been principally reported in the parotid gland. It displays histologically a striking similarity to ductal carcinoma of the breast.

OBSERVATION

We report the case of a salivary duct carcinoma arising in the parotid gland of a 62 year-old man. The fact that the tumor was confined to the parotid gland has allowed a radical treatment. After two year follow-up, there was no evidence of recurrence.

DISCUSSION

This tumor is characterized clinically by local aggressiveness, frequent metastatic evolution and poor prognosis. This case report illustrates both the clinicopathological features and the prognostic factors of this entity.

[Prevalence of Epstein-Barr virus in Sjögren's syndrome in Tunisia]

PURPOSE

The cause of Sjögren's syndrome is unclear. Several studies suggested the role of Epstein-Barr virus (EBV) in the pathogenesis of this syndrome, but this always remains a subject of numerous controversies. The purpose of this study was to evaluate the prevalence of EBV in Sjögren's syndrome in Tunisia.

METHODS

A series of 31 paraffin-embedded biopsies of salivary glands from patients with Sjögren's syndrome were studied in comparison with 19 control glands. EBV was investigated by PCR, EBERs in situ hybridization and by immunohistochemistry for the detection of LMP1, EBNA2 and ZEBRA.

RESULTS

EBV DNA was detected by PCR in 3 of 22 PCR beta-globin positive Sjögren's syndrome cases (13.6%) and in 2 of 17 PCR beta-globin positive control glands (11.7%); in situ hybridization positivity was noted in rare lymphocytes in the 3 EBV positive cases of Sjögren's syndrome, but not in control glands; immunohistochemical study was negative in all cases.

CONCLUSION

EBV infection does not appear to play a significant role in the pathogenesis of Sjögren's syndrome in Tunisia.

[Molecular characterization of Epstein-Barr virus associated with classical Hodgkin's lymphoma in Tunisia: prevalence of the LMP1 oncogene deletions and A and B viruses strains]

Epstein-Barr virus (EBV) is detected in Hodgkin's lymphoma (HL) at variable frequencies, depending on various factors including the geographic location. The prevalence of EBV is high among HL diagnosed in the region of the center of Tunisia. The aim of the current work was to define the genotypic features of EBV in a series of EBV-positive HL in this area, in comparison to those of EBV found in association with benign lymphoadenopathies. A 30 bp and a 69 bp deletion within the LMP1 gene were detected in 41% and 11% of HL cases, respectively. In reactive lymph nodes, the 30 bp deletion was found in 43% of the cases. Type A EBV was detected in 84% of HL cases and in 96% of reactive lymphoadenopathies, and type B EBV was detected in others. No significant association was found between histological type of HL, age of the patients, or stage at diagnosis, and the molecular configuration of LMP1. However, LMP1 deletions were found more frequently among male patients. The significance of these results is discussed.

[Cord compression secondary to extramedullary hematopoiesis in a patient with beta-thalassaemia]

Extramedullary hematopoiesis (EMH) is a common manifestation in beta-thalassemia, but can also occur in several clinical hematologic disorders or neoplasms. It has been reported in almost all sites of the body. Often asymptomatic, it can be manifested by compression of the adjacent organs. Spinal cord compression as a consequence of EMH in the intraspinal epidural space is an extremely rare complication. We report a case of a 34 year old man who was hospitalised for complete paraplegia and spasticity of both lower limbs; spinal cord compression on D4-D8 by EMH was diagnosed by MRI and confirmed by histologic examination.

[Analysis of immunoglobulin heavy chain genes rearrangement by PCR from paraffin-embedded tissue in B-cell lymphomes in Tunisia]

OBJECTIVE

To study the lymphoid clonality on Tunisian B-cell lymphomas cases by polymerase chain reaction (PCR)-based techniques using DNA from paraffin-embedded tissues.

MATERIAL AND METHODS

Here we conducted a retrospective PCR clonality study on 73 cases of B-cell lymphomas and 12 reactive lymphoid tissues. The quality of DNA extracted was tested by beta-globin PCR. Consensus primers directed at the FRIII-VH and FRII-VH regions of the immunoglobulin heavy chain (IgH) gene were used to detect clonality.

RESULTS

The results showed that 52 of 73 (71%) B-cell lymphomas exhibited good quality of amplifiable DNA. Clonality was found in 77% of cases using the set of primers FRIIIa/LJH/VLJH and in 65.5% using the set of primers FRIIa/LJH/VLJH. Lymphomas derived from pregerminal centre showed a high rate detection of clonal IgH gene rearrangement (100%) compared to other group of tumors derived from germinal centre or postgerminal centre (74.5%). None of the polyclonal controls gave a clonal pattern.

CONCLUSION

This is the first large series of PCR clonality study of IgH gene rearrangements on B-cell lymphoma from Tunisia. Our results were similar to other reports in terms of sensitivity and specificity of these techniques and confirm the interest of that PCR for detecting clonal IgH gene rearrangements in lymphoma.

[Massive ovarian oedema]

Massive ovarian oedema is a rare tumor-like condition predominantly found in young women. It is considered malignant until otherwise proven because of its solid nature. The pre-operative diagnosis is very difficult. The frozen section examination can help for diagnosis and ensures conservative treatment with ovarian preservation. The authors report a case of a 23-years-old woman with right ovarian mass findings on ultrasound imaging. The diagnosis of massive ovarian oedema was made on frozen section after a right oophorectomy. Although most of reported cases has been handled by oophorectomy, the conservative treatment must be the ruler, especially since the disorder is benign and reaches the youth.