In vivo behavior of complete human oral mucosa equivalents: characterization in athymic mice.

BACKGROUND AND OBJECTIVE: The interest in tissue engineering as a way to achieve repair of damaged body tissues has led to the carrying out of many studies whose results point to the potential effectiveness of these methods. In a previous study, we reported the obtaining of complete autologous oral mucosa equivalents (CAOMEs), characterized by oral immature keratinocytes and stem cells on an autologous plasma and fibroblast scaffold. The purpose of this study is to show their behavior in vivo, by using them as free grafts in experimental animals, and to demonstrate their potential capacity to regenerate oral mucosa. MATERIAL AND METHODS: We engineered CAOMEs, as previously described. All CAOMEs thus obtained were used as free grafts in nu/nu mice. To assess their evolution in vivo, we studied their histological and immunohistochemical features by using AE1/AE3 pancytokeratin, the 5/6 cytokeratin pair, cytokeratin 13, laminin 5, collagen IV, vimentin, p-63 and Ki-67, at 7, 14 and 21 d. RESULTS: The structure became progressively closer to that of oral mucosa samples. Cytokeratin 5/6 staining became increasingly intense in the basal and suprabasal layers, and cytokeratin 13 was exclusively positive in the superficial layers. The basal membrane was completed in 21 d. Vimentin showed a correct formation of the chorion. The increasingly positive staining of p-63 and Ki-67 indicated that the regeneration process was taking place. CONCLUSION: The present study shows the potential regenerative capacity of the CAOMEs by their ability to reach maturity similar to that seen in oral mucosa.

Distinctive clinicopathological associations of amplification of the cortactin gene at 11q13 in head and neck squamous cell carcinomas.

Amplification of the 11q13 region is a prevalent genetic alteration in head and neck squamous cell carcinoma (HNSCC). We investigated the clinical significance of cortactin (CTTN) and cyclin D1 (CCND1) amplification in both malignant transformation and tumour progression. CTTN and CCND1 amplification was analysed by differential and real-time PCR in a prospective series of laryngeal/pharyngeal carcinomas and archival premalignant tissues. CTTN mRNA and protein expression were respectively determined by real-time RT-PCR and immunohistochemistry, and correlated with gene status. Molecular alterations were associated with clinicopathological parameters and disease outcome. CTTN and CCND1 amplifications were respectively found in 75 (37%) and 90 (45%) tumours. Both correlated with advanced disease; however, only CTTN amplification was associated with recurrence and reduced disease-specific survival (p = 0.0022). Strikingly, CTTN amplification differentially influenced survival depending on tumour site (p = 0.0001 larynx versus p = 0.68 pharynx) and was an independent predictor of reduced survival in the larynx (p = 0.04). CCND1 amplification was detected in early tumourigenesis and increased with the severity of dysplasia. Importantly, CTTN amplification was only found in high-grade dysplasias that progressed to invasive carcinoma. CTTN gene status strongly correlated with mRNA and protein expression. Furthermore, CTTN overexpression correlated significantly with reduced disease-specific survival (p = 0.018). Taken together, these data indicate that CTTN may serve as a valuable biomarker to identify patients with laryngeal tumours at high risk of recurrence and poor outcome.

[MALT B cell lymphoma with kidney damage and monoclonal gammopathy: a case study and literature review]. / Linfoma de células B tipo MALT con afectación renal y gammapatía monoclonal: presentación de un caso y revisión de la literatura.

We report a case of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) involving the left kidney and simultaneous onset of a monoclonal gammopathy IgM kappa. No predisposing local inflammatory condition was identified. Following left nephrectomy, the renal specimen showed the centrocyte like cells and lymphoid cells in the lymphoepithelial lesions were positive for CD20 and CD79α. The neoplastic cells expressed monotypic cytoplasmic IgM kappa. The demonstration of bone marrow cells of B-lineage expressing the same monoclonal protein as the tumor suggested bone marrow involvement, even in the absence of identical morphology. Despite chemotherapy and rituximab treatment, clinical follow-up showed right kidney extension with high-grade transformation, and finally systemic dissemination. This case illustrates that the kidney is among the sites that may be involved by MALT B-cell lymphomas in a primary or secondary fashion, and the need for expanded investigation of the possible dissemination. We review the literature on this unusual extranodal lymphoma.

Primary cutaneous large B-cell lymphoma: the relation between morphology, clinical presentation, immunohistochemical markers, and survival.

The histogenesis, morphology, immunophenotype, and clinical behavior of cutaneous large B-cell lymphomas (CLBCL) are largely a matter of controversy. We performed an investigation to determine whether CLBCL have features that differentiate them from other large B-cell lymphomas and whether CLBCL is itself a heterogeneous group. To this end, we reviewed the main characteristics of a series of 32 cases of LBCL found in the skin. We reviewed the clinical findings and paraffin sections of the tumors from these 32 patients. The immunohistochemical study performed included p53, MIB1, Bcl2, Bcl6, and CD10 markers. We carried out statistical analysis of these data (univariate and multivariate), seeking an association between the features of the tumors and clinical outcome, as defined by failure-free survival time. Only one patient died as a consequence of the lymphoma. Nevertheless, the accumulated probability of survival without failure at 48 months was 0.46. The number, type, and localization of the lesions were not associated with variations in either survival or failure-free survival. The expression of p53 was negative in this group of CLBCL, whereas Bcl-2 expression or localization in the lower leg did not relate to any other significant feature. Histologic examination of the cases disclosed three different groups: Grade III follicular lymphomas (FLs), monomorphous large B-cell lymphomas (LBCL type I), and LBCL with an admixed component of small B-lymphocytes (LBCL type II). Grade III FL (11 cases) tended to be found in the head and neck and showed CD10 expression in a majority of cases. A higher probability of lymph node relapses was associated with cases located in the head and neck and with CD10+ tumors. Cutaneous large B-cell lymphomas are indolent tumors, but follow an insidious course. Our data support the interpretation that CLBCL is a heterogeneous condition; comprises some LBCL derived from CD10+ germinal center cells which manifests more frequently as tumors in the head and neck region, with an increased probability of relapse in lymph nodes [1] and has some distinctive morphologic features. The existence of a component of small B-cells within the other CLBCL could lend support to the theory that some of these tumors, more than arise de novo, may have originated in preexistent small B-cell lymphomas, but no firm evidence of this is provided in this study.

Mutation analysis of the p53, APC, and p16 genes in the Barrett's oesophagus, dysplasia, and adenocarcinoma.

AIMS: To study the loss of heterozygosity and the presence of mutations at the p53, p16/CDKN2, and APC genes in Barrett's oesophagus, low grade dysplastic oesophageal epithelium, and adenocarcinoma of the oesophagus; to relate the presence of alterations at these genes with the progression from Barrett's oesophagus to adenocarcinoma. METHODS: DNA was extracted from paraffin blocks containing tissue from Barrett's oesophagus (12 samples), low grade dysplasia (15 cases), and adenocarcinoma (14 cases). Loss of heterozygosity (LOH) at the p53, p16, and APC genes was determined by comparing the autoradiographic patterns of several microsatellite markers between the normal tissue and the malignant tissue counterpart. SSCP was used to determine the presence of mutations at p53 (exons 5 to 8), p16 (exon 2), and APC. Homozygous deletion of the p16 gene was defined through polymerase chain reaction followed by Southern blot. RESULTS: LOH at the p53, p16, and APC genes was not observed in Barrett's oesophagus without dysplasia, and increased to 90% (p53), 89% (p16), and 60% (APC) in the adenocarcinomas. The p53 gene was mutated in only two adenocarcinomas (codons 175 and 245). In one case a mutation at the APC gene (codon 1297) was found. No patient had mutation at the second exon of p16. However, this gene was homozygously deleted in three of the 12 adenocarcinomas. CONCLUSIONS: The tumour suppressor genes p53, p16, and APC are often deleted in adenocarcinomas derived from Barrett's oesophagus. Mutations at these genes are also found in the adenocarcinomas, including the homozygous deletion of the p16 gene. However, the absence of genetic alterations in the Barrett's oesophagus and the low grade dysplastic epithelia suggest that mutations at these genes develop later in the progression from Barrett's oesophagus to adenocarcinoma.

Expression and clinical significance of pepsinogen C in resectable pancreatic cancer.

Pepsinogen C is an aspartyl-proteinase usually involved in the digestion of proteins in the stomach, and an androgen- inducible protein in breast cancer cells. In this study we evaluated its expression and clinical significance in patients with resectable pancreatic cancer. Pepsinogen C expression was examined by immunohistochemical methods in a series of 73 pancreatic carcinomas. The prognostic value of pepsinogen C was retrospectively evaluated by multivariate analysis. A total of 21 (28.8%) pancreatic carcinomas stained positively for pepsinogen C. The percentage of pepsinogen C-positive tumors was significantly higher in well-differentiated tumors (38.3%) than in moderately differentiated (15.8%) and poorly differentiated (O%) tumors (p<0.05). In addition, statistical analysis revealed that pepsinogen C expression was associated with clinical outcome. Thus, patients with pepsinogen C-negative tumors have a poorer overall survival than those with pepsinogen C-positive tumors. Our results led us to consider that the expression of pepsinogen C may represent a useful biological marker in pancreatic cancer. Expression of this protein may be a marker of gastric-type differentiation of the tumors and it might also reflect the existence of a complete hormone receptor pathway in a subset of pancreatic carcinomas.

Mismatch repair protein MSH2 expression and prognosis of colorectal cancer patients.

INTRODUCTION AND AIMS: The role of genetic factors in the etiology and prognosis of patients with sporadic colorectal cancer is controversial. We have therefore investigated the biological and clinicopathological influence of immunohistochemical MSH2 expression in colorectal cancer. PATIENTS AND METHODS: A total of 49 consecutive patients with unselected colorectal cancer operated on in our unit were included in the study. All tumors were resected and tumor specimens were evaluated for MSH2 expression. Clinicopathological data and patient survival were correlated with MSH2 staining. Uni- and multivariate analyses were performed. The minimum follow-up period was five years. RESULTS: Curative resection was performed in 34 patients (64.9%), 14 of whom subsequently relapsed. At the end of the overall follow-up 25 (51%) patients had died, 21 of cancer-related causes. Twenty-eight patients (57.1%) were negative for MSH2 staining. Only vascular invasion was significantly correlated with MSH2 expression (lower median values; p=0.04). The overall median survival was 47.9 months (95% CI=27-86.6%). Multivariate analysis of variables in relation to survival showed that T stage (p=0.001), N stage (p<0.001) and MSH2 expression (p=0.01) were independent factors for survival. CONCLUSIONS: Reduced MSH2 expression is frequent in unselected colorectal cancer patients. Only vascular invasion was correlated with MSH2 expression in this study. Survival was related to TN stage and MSH2 staining.

Large surface of cultured human epithelium obtained on a dermal matrix based on live fibroblast-containing fibrin gels.

The aim of this study was to develop a new keratinocyte culture system on a dermal equivalent suitable for skin wound closure. Our dermal matrix is based on a fibrin gel from plasma cryoprecipitate containing live human fibroblast (from human foreskin). Keratinocytes obtained from primary culture according to the Rheinwald and Green method, were seeded on the gel at different seeding ratios. In all cases, the keratinocytes plated on the dermal equivalent grew to confluence and stratified epithelium was obtained within 10-15 days in culture. Early expression of basal membrane proteins was detected by immunostaining with laminin and type IV collagen antibodies. Cell proliferation was detected both in the epidermal layer and in the fibroblast embedded in the gel as assessed by BrdU incorporation. Detachment of composite cultures from dishes or flasks is a simple and quick procedure without the need for dispase treatment. Grafting of composite cultures to nude mice gave rise to an orderly stratified, orthokeratinized epithelium resembling human epidermis. A number of advantages including a large expansion factor without the need of 3T3 feeder layer, the availability of fibrin/plasma cryoprecipitate from blood banks and the versatile manipulation of composite cultures suggest that this system could be suitable for the definitive coverage of severely burned patients.

De novo desmoplastic neurotropic melanoma of the lower lip: a neoplasm with ominous behavior.

Desmoplastic neurotropic melanoma represents a rare histologic variant of malignant melanoma that is characterized by a proliferation of spindle cells in a densely collagenous stroma with pronounced neurotropism. A 60-year-old man appeared for evaluation of a mass in the lower lip. The labial mucosa was intact, and the lesion had been present for 2 months. The tumor was surgically removed, and after immunohistochemical and ultrastructural analysis it was diagnosed as desmoplastic neurotropic melanoma. The tumor recurred 6 months later, with involvement of the inferior alveolar nerve.

[Remission of severe disease induced by CMV and lymphoproliferative post-transplant disease after changing the immunosuppressive regime]. / Remisión de enfermedad severa por citomegalovirus y enfermedad linfoproliferativa post-trasplante en un receptor de trasplante renal tras terapia con ganciclovir y cambio en la medicación inmunosupresora.

We describe a renal transplant recipient, with overimmunosuppression induced by the interaction of tacrolimus and fluconazole, who developed two severe diseases produced by two different viruses of the herpes group (cytomegalovirus [CMV] disease and posttransplant lymphoproliferative [PTLD] disease EBV-related). Detection of Epstein-Barr virus (EBV) DNA in the blood preceded the histological diagnosis of PTLD. Both diseases improved after changes in the immunosuppressive regime and treatment with ganciclovir. Because CMV infection is a risk factor in developing PTLD, and the clinical and endoscopic manifestations of both diseases could be become confused, PTLD should be excluded in EBV seronegative patients that develop CMV disease. The detection of the EBV genome in blood could help in the early diagnosis of PTLD in these patients.

[Neuroendocrine carcinoma of the ampullar region with oat-cell histological features and adenocarcinoma]. / Carcinoma neuroendocrino de la región ampular con rasgos histológicos de "oat-cell" y adenocarcinoma.

We report a case of primary duodenal carcinoma showing neuroendocrine and glandular differentiation, in a 65-years-old male. Both components were closely related and transition between them was observed. The neuroendocrine component was composed of an undifferentiated "oat-cell" type, with positive immunostaining for neuroendocrine and epithelial markers. Ultrastructural findings confirmed this double differentiation, with dense cytoplasmatic granules of neurosecretory type. The neuroendocrine component showed greater aggressiveness with lymph node metastasis.

[Angiomyoma of the retropharyngeal space]. / Angiomioma del espacio retrofaríngeo.

We report the case of a 65-year-old male patient with an angiomyoma of the retropharyngeal space. Angiomyoma is a tumour that arises from the smooth muscle in the wall of blood vessels. It is a relatively rare tumour of the head and neck, mostly in deep locations. This one is the second reported angiomyoma of the retropharyngeal space. Although image examinations and fine needle aspiration (FNA) did point to a vascular tumour, the diagnosis of this lesion is made by on excisional biopsy and histological staining with vimentin, desmin, actin or myosin. The treatment is excision of the tumour and recurrence is exceptional.

Intraosseous mandibular schwannoma mimicking an odontogenic keratocyst, with a postsurgical pathological fracture.

OBJECTIVE: Schwannomas are slowly growing tumours derived from Schwann cells. We present a clinical case of schwannoma in the mandibular angle. METHOD: Case report and a review of the world literature concerning intraosseous schwannoma of the maxillofacial region. RESULTS: Schwannomas or neurilemmomas are slow-growing, benign neoplasms derived from Schwann cells. Intraoral lesions are unusual and intraosseous schwannomas are even rarer, representing less than 1 per cent of benign primary tumours of the bones. We present a clinical case of schwannoma in the mandibular angle mimicking a keratocystic odontogenic tumour, with a complicated posterior evolution. CONCLUSION: Clinically, neurilemmomas are slow-growing tumours which may be present for years before becoming symptomatic. Radiographically, the image may be suggestive of a benign process such as an odontogenic keratocyst. Histological analysis of the specimens obtained is extremely important in order to establish the final diagnosis.

Expression of MMP-7 and MT1-MMP in oral squamous cell carcinoma as predictive indicator for tumor invasion and prognosis.

BACKGROUND: Squamous cell carcinoma of the oral cavity is a highly invasive neoplasm that spreads locally and metastasizes to regional lymph nodes. This process involves multiple proteolytic enzymes including matrilysin (MMP-7) and membrane type I-matrix metalloproteinase (MT1-MMP). This study was designed to explore the association between MMP-7 and MT1-MMP in the invasiveness and prognosis of oral squamous cell carcinoma (OSCC). METHODS: About 4-microM, formalin-fixed, paraffin-embedded tissue sections from 69 patients with OSCC were immunohistochemically studied using specific antibodies against MMP-7 and MT1-MMP proteins. Immunostaining was semiquantitatively scored, and results were correlated with histologic and clinical variables including clinical behavior and survival. RESULTS: MMP-7 was observed only in cancer cells, and MT1-MMP in both tumoral tissue and stroma. MMP-7 expression was significantly correlated with lymph node metastasis (P = 0.03; RR = 3.2). MT1-MMP showed a significant association with TIMP-2 (in N+ cases) and p53 expression (P = 0.01). MMP-7 and MT1-MMP displayed a survival relevance, and in multivariate analysis they were independent prognostic indicators, particularly in neck node-positive cases.

[Folliculotropic mycosis fungoides. Study of four cases]. / Micosis fungoide folicular. Estudio de cuatro casos.

Folliculotropic mycosis fungoides is a variant of mycosis fungoides characterized by the presence of folliculotropic infiltrates, often with sparing of the epidermis, and preferential involvement of the head and neck. We report our experience with four cases of folliculotropic mycosis fungoides followed in our department in the last years. There are four patients (three men and one woman) aged 45 to 68 years. Clinically the lesions presented as cysts, comedones, follicular papules and plaques with follicular plugging. The histopathological study showed a peri and intrafollicular infiltrate with partial or total sparing of the epidermis. This infiltrate was mainly composed of atypical lymphocytes. Some cystic formations were also observed. Three cases showed mucin deposits and one showed syringotropism. The immunohistochemical analysis was positive for CD3, CD5 and CD4. All patients received different treatments based on the stage of their disease. One of them died of septic shock and the rest showed partial responses and frequent relapses.

Detection of occult disease in tissue donors by routine autopsy.

The transmission of infectious and neoplastic diseases is a potential risk of tissue allografting. In this study, we analyzed the occurrence of occult disease in tissue donors as detected by standard screening and autopsy. Whereas 18% of the potential donors initially evaluated were eliminated on the basis of their medical and social histories, laboratory screening and autopsy revealed that an additional 9% of tissue donors had undetected, transmissible disease that prohibited tissue donation. This report emphasizes once again the risk of occult disease being transplanted with grafts and the need for autopsy to reduce the likelihood of this occurring. If donor selection, appropriate screening tests, and autopsy are carefully carried out, the risk of transmitting diseases from tissue allografts can be kept to a minimum.