Diagnostic efficacy of electron microscopy and pleural effusion cytology for the distinction of pleural mesothelioma and lung adenocarcinoma.

The diagnosis of malignant pleural mesothelioma (MPM) is challenging and requires immunohistochemistry or electron microscopy assays to specifically differentiate MPM from lung adenocarcinoma. An ultrastructural study of fresh tissue is considered to be the "gold standard." In most cases, the first diagnostic approach is performed on pleural effusion, and in some patients, this is the only available sample for diagnosis. The aim of the present study is to evaluate if an examination of pleural effusion samples based on electron microscopy (EMpe) is a useful tool for the differential diagnosis of MPM and lung adenocarcinoma. An EMpe study was performed in 25 pleural effusion samples. Histological and immunohistochemical markers confirmed the diagnosis of either mesothelioma (5) or adenocarcinoma (20). Of the five cases that were diagnosed with mesothelioma, two samples (40%) showed cells with "bushy" microvilli, which are characteristic of mesothelioma, by EMpe, and three were acellular (60%). Of the 20 cases of adenocarcinoma, EMpe showed cells with short microvilli in 9 (45%), and 11 were acellular (55%). EMpe identifies unequivocal morphological changes that are useful for the differential diagnosis of MPM or adenocarcinoma when the pleural effusion sample contains evaluable tumor cells.

Expression of hormonal receptors in osteosarcomas of the jaw bones: clinico-pathological analysis of 21 cases.

BACKGROUND: Sexual hormones have an important role in many hormone-dependent tumors like breast and prostate carcinomas, and also a relationship has been found with bone metabolism and bone tumors. Some studies have demonstrated that the expression of hormonal receptors (HR) in osteosarcomas (OS) of long bones is associated with gender, histological grade, histological type, and a possibly may be connection with pathogenesis and evolution. However, to our knowledge there are no studies of HR in osteosarcomas of craniofacial bones (OS-CF). OBJECTIVE: To assess the expression of hormonal receptors in OS-CF. MATERIAL AND METHODS: Twenty one cases of OS-CF were included in this study. Clinical outcome was obtained from clinical charts. Histological sections were reviewed, and immunohistochemistry studies for estrogen, progesterone and androgen receptors were performed. RESULTS: A striking female predominance was found (2:1), with a median age of 35 years. The predominant type of OS was osteoblastic (52.4%), and histological grade was high in 86%. Follow-up was obtained in 13 cases and ranged from 6 to 118 months (median 29 months). There were 8 patients (61.5%) dead or alive with progressive disease in the last follow up. Negative expression of HR was found in 19/21 cases; one showed weak nuclear expression for estrogen receptor, and another for androgen receptor. Progesterone receptor was negative in all cases. CONCLUSIONS: OS-CF mostly affected females, most of them were of the osteoblastic type and of high grade. Hormonal expression was practically negative in osteosarcoma of craniofacial bones.

[National consensus of diagnosis and treatment of non-small cell lung cancer]. / Consenso nacional de diagnóstico y tratamiento del cáncer de pulmón de células no pequeñas.

Mexican specialists in oncology, oncologic surgery, thoracic surgery, pneumology, pathology, molecular biology, anesthesiology, algology, psychology, nutrition, and rehabilitation (all of them experts in lung cancer treatment) in order to develop the National Consensus on Lung Cancer. The consensus has been developed as an answer to the need of updated Mexican guidelines for the optimal treatment of the disease, as well as to the requirements that such guidelines be established by multidisciplinary panel, depicting the current attention given to cancer lung cases in Mexico. Thus, this paper analyses the epidemiological review, screening, diagnosis, staging, pathology, translational medicine, and the suitable therapies for early, locally advanced, and metastatic disease in the first, second, and third lines of management, as well as rehabilitation and palliative measures.

HPV Prevalence and Predictive Biomarkers for Oropharyngeal Squamous Cell Carcinoma in Mexican Patients.

BACKGROUND: Worldwide prevalence of Oropharyngeal Squamous Cell Carcinoma (OPSCC) has increased, affecting mostly young males. OPSCC associated with Human Papillomavirus (HPV) infection exhibits particular characteristics in terms of response to treatment, hence HPV has been proposed as a prognostic factor. The impact of HPV positivity and associated biomarkers on OPSCC in the Mexican population has not been addressed. Therefore, the analysis of OPSCC prognostic markers in the Mexican population is necessary. METHODS: Retrolective study in Mexican OPSCC patients, where HPV prevalence, p16 and EGFR levels were assessed using INNO-LiPA and immunohistochemistry. RESULTS: We found an HPV prevalence of 57.6% in OPSCC cases treated at a reference center in Mexico. HPV and p16 positivity, as well as EGFR, associate with better outcomes in OPSCC patients, and they also promote reduced death risk. Notably, HPV presence and p16 positivity showed a significant association with disease-free survival (DFS), with a HR of 0.15 (p = 0.006) and a HR of 0.17 (p = 0.012), respectively, indicating a possible role as predictive biomarkers in Mexican OPSCC patients. CONCLUSIONS: Our results reflect the clinical utility of p16 analysis to improve overall survival (OS) and to predict recurrence in oropharyngeal cancer. These results position p16 and HPV as predictive biomarkers for OPSCC.

Hybrid salivary gland tumor of the upper lip or just an adenoid cystic carcinoma? Case report.

UNLABELLED: A 65 year-old male patient with a one year-duration tumoral growth located in the upper lip was diagnosed on incisional biopsy as epithelial-myoepithelial carcinoma. After wide surgical excision the histopathological analysis revealed the lesion was composed predominantly (>90%) of adenoid cystic carcinoma. In new sections it was found a very small and isolated area of adenoid cystic carcinoma at the bottom of the incisional biopsy. As surgical margins were free of lesion, no adjuvant treatment was given. The occurrence of a transitory ischaemic attack at 36 months of follow-up led to a neurological and MRI evaluation, which disclosed a well-defined 3.5 x 3 cm lesion suggestive of metastasis, located on the right temporal area. The lesion was surgically removed and a histopathological diagnosis of neurocysticercosis was rendered. After 40 months of follow-up there is no evidence of recurrence. CONCLUSION: True hybrid tumors of salivary glands are rare and treatment in each case should be done according to the component with the higher aggressiveness. However, the occurrence of epithelial-myoepithelial carcinoma areas within an adenoid cystic carcinoma seems to be a frequent finding, and because both lesions share a common origin, some authors consider that this may not be a true hybrid neoplasm but a variant of the latter.

Necrotizing sialometaplasia of the palate associated with angiocentric T-cell lymphoma.

In this article we present 2 cases of necrotizing sialometaplasia (NS) associated with angiocentric lymphoma of the midline. Immunohistochemical analysis confirmed a T-cell origin, and in situ hybridization in one case revealed its relationship to Epstein-Barr virus. These findings suggest that vascular occlusion by the neoplastic cells produces ischemia, which leads to local infarction contributing to the salivary gland lesion. To our knowledge, the association between angiocentric lymphoma and NS has been previously reported in only one instance, and we suggest that this particular type of lymphoma should be added to the list of related conditions for NS.

Primary extracranial meningioma of the mandible.

Meningiomas are benign tumors of mesodermal origin that arise from arachnoid cell clusters that penetrate the dura to form arachnoid villi. These neoplasms represent one of the most common neoplasms developing within the central nervous system and are usually located at points of entry of vessels and nerves through the dura. Extracranial meningiomas (EM) comprise only 2% of all meningiomas, and only six cases of primary EM of the jawbones have been described to date. They may arise as an extension of intracranial meningiomas or as primary tumors and may be clinically indistinguishable from other benign tumours of the jaws, as they usually present as a well-delineated unencapsulated tumors. In this article a case of primary intramandibular primary EM that appeared as a well-defined osteolytic radiolucent lesion of the jaw is reported. The salient clinico-pathological features of this case is compared to those previously reported in the literature and differential diagnosis and therapeutic considerations are discussed.

Odontogenic myxoma: clinico-pathological, immunohistochemical and ultrastructural findings of a multicentric series.

The aim of this study was to analyze the clinico-pathological and immunohistochemical features of 62 cases of odontogenic myxoma (OM) diagnosed in three Oral Pathology Diagnostic Services in Latin America, as well as to describe the ultrastructural features of three of these cases. OM showed a wide age range (9-71 years), with a mean of 27.97 yr (SD: 11.01) and a male to female ratio of 1:2.2. Mandible was affected in 37 cases (59.6%) and maxilla in 25 (40.4%), with 61.3% located in the posterior region. Thirty-nine cases (62.9%) were multilocular and 23 (37.1%) unilocular. Size ranged from 1 to 13 cm, (mean: 5.2 cm). Thirty-seven multilocular (54.8%) and 6 unilocular lesions (26%) were larger than 4 cm (p<0.05). Epithelial islands were identified in 5 cases (8%) on H&E stained sections, but AE1/AE3 and CK14 disclosed these structures in 15 cases each (24.2%); CK5 was positive in 8 (12.9%); CK7 in 2 (3.2%) and CK19 in only 3 cases (4.8%). All cases were negative for CKs 8 and 18, S-100 protein, NSE and CD68, and showed a low index of expression of Bcl2 and ki-67 proteins (<1%). Mast cell antibodies showed these cells in 45 cases (72.6%). Myofibroblastic differentiation evidenced by myofilaments and fibronexi was found in one case out of the three studied by TEM and 29 cases (46.7%) were positive by immunohistochemistry for alpha actin. In conclusion, only a minority of OM had epithelial islands, and only 3 cases expressed CK 19, indicating an odontogenic epithelium origin. Immunohistochemical and ultrastructural findings suggest that OM is a mesenchymal neoplasm in which several factors may contribute to its pathogenesis, including myofibroblastic differentiation and the participation of mast cell products. However, further investigations are needed to better understand the participation of these elements in this particular neoplasm.

Macroglossia caused by adenoid cystic carcinoma. Case report.

A 33-year-old woman sought medical care at our institution for macroglossia. She had been treated before with tracheostomy and gastrostomy due to an adenoid cystic carcinoma (ACC) of the mobile tongue, in clinical stage IVC. She was subjected to total glossectomy with larynx preservation, modified radical dissection of the right neck and of the left supraomohyoid muscle, as well as reconstruction using a free flap from the rectus abdominus. The histological report described a 15x11 cm solid type ACC of the mobile tongue (grade III), with infiltration to adjacent soft tissues, vascular and lymphatic vessels, as well as two metastatic lymph nodes in the right neck dissection. One month after surgery, bone and bilateral pulmonary tumor activity became evident. In advanced-stage tumors, treatment must be individualized, and when accompanied by severe deterioration of the quality of life, surgery is recommended independently from the extension, provided that a good reconstruction is accomplished.

Brain angiometastasis from a non-seminomatous germ cell tumor: A case report.

INTRODUCTION: Brain metastasis from non-seminomatous germ cell tumors (NSGCT) is rare. Herein, we describe the second reported case of brain metastasis from a NSGCT with high-flow arteriovenous (AV) shunts, and propose a novel surgical treatment plan. CLINICAL CASE: The patient was a 34-year-old male who presented with hemiparesis and hemianesthesia. Magnetic resonance angiography revealed three vascular lesions with afferent vessels and efferent vessels. Angiography displayed two high-flow AV shunts. During angiography, the patient experienced sudden neurological deterioration and consequently underwent surgery. During surgery, a lesion with large AV shunts was observed, with arterialized drainage veins, pedicled arterial vessels affluent to the nidus, and an absent pial plane. The surgical technique was adapted to lesion morphology using special bipolar forceps. Histological and immunohistochemical tests confirmed that the lesion was a NSGCT. DISCUSSION: NSGCTs are clinically more aggressive than seminomas. Lesions with an AV shunt and glioma combination are designated as angiogliomas. Therefore, we termed the lesion in the present case as an "angiometastasis," which was formed from numerous AV shunts. The use of presurgical embolization has been reported to improve long-term survival in patients with intra-axial hypervascular tumors with AV shunts. CONCLUSION: We here propose a novel strategy for the management of hypervascular brain metastasis from NSGC, consisting of angiography, tumor embolization, and the use of an angiometastatic surgical technique with special bipolar forceps. This case report may help neurosurgeons make better surgical decisions in the management of highly vascularized brain metastasis.

Cervical Intramedullary Schwannoma: Case Report and Review of the Literature.

Cervical intramedullary schwannomas are extraordinarily rare. Gross total resection is the best therapeutic option for these types of tumors. Although rare, intramedullary schwannomas should be considered as a differential diagnosis of intramedullary lesions since a good prognosis can be guaranteed to the majority of these patients. We present a case of a cervical intramedullary schwannoma surgically treated in a 19-year-old male patient who initially presented with motor neuron disease.

Dermatofibroma and dermatofibrosarcoma protuberans: a comparative ultrastructural study.

Dermatofibroma (DF) and dermatofibrosarcoma protuberans (DFSP) are dermal tumors whose histogenesis has not been well defined to date. The differential diagnosis in most cases is established in routine H/E sections and may be confirmed by immunohistochemistry, but there are atypical variants of DF with less clear histological differences and non-conclusive immunohistochemical results. In those cases, electron microscopy studies may be useful in establishing the diagnosis. The authors describe in detail the ultrastructural characteristics of 38 cases of DFSP and 10 cases of DF. The objective was to establish the ultrastructural features for differential diagnosis, and to identify the possible histogenesis of both neoplasms. DFSP is formed by stellate or spindled cells with long, slender, ramified cell processes joined by primitive junctions. Subplasmalemmal densities were frequently seen in the processes. Another common finding was the presence of multivesicular buds (MVB), peculiar structures that contain microvesicles abutting from the cell membrane. In contrast, DF is characterized by a proliferation of multiple capillary vessels with prominent endothelium and a perivascular population of ovoid or spindled cells devoid of cell processes. These latter cells featured intracytoplasmic lipid material (p < .001), infrequent subplasmalemmal densities (p < .001), and absence of MVB (p < .001). With the ultrastructural characteristics and the constant expression of CD34 in DFSP, a probable origin in dermal dendrocytes is postulated for this tumor. The histogenesis of DF is less clear, but an origin from FXIIIa modified perivascular dermal dendrocytes is proposed.

Venous aneurysms of the extremities. Report of 4 cases and review of literature.

Venous aneurysms are lesions that can be difficult to diagnose and may be a source of significant morbidity. Venous aneurysms have been reported to occur in most major veins, neck, central thoracic veins, and extremities. The authors report 4 cases of venous aneurysms: 1 of the upper and 3 of the lower extremity. All patients underwent aneurysmectomy with end-to-end anastomosis and no complications after surgery were reported. These cases are presented along with a review of literature and their origin, diagnosis, and treatment.

Synchronic nasopharyngeal and intraparotid warthin tumors: A case report and literature review.

Warthin tumor is the second most frequent benign salivary gland tumor after pleomorphic adenoma; it occurs almost exclusively in the parotid gland and peri-parotideal lymph nodes, although it may rarely present in other locations. It may be multicentric and bilateral in a small percentage of cases. Nasopharyngeal Warthin tumor is very rare, and the presence of a synchronic WT involving nasopharynx and parotid is an exceptional event, as it has been described only twice in the literature. In this article we report an additional case of a synchronic Warthin tumor and review the related literature. Key words:Warthin tumor, synchronic WT, multicéntrico, nasopharynx.

Synovial sarcoma of the larynx treated by supraglottic laryngectomy: case report and literature review.

We describe a case of synovial sarcoma of the larynx, and we discuss the use of fluorescence in situ hybridization (FISH) in confirming the diagnosis. The patient was a 21-year-old woman who presented with a recurrence of a previously resected supraglottic tumor of the aryepiglottic folds. A horizontal supraglottic laryngectomy was performed, and the 0.5-cm tumor was resected. Histopathologic study suggested that it was a biphasic malignant tumor compatible with a synovial sarcoma. The diagnosis of synovial sarcoma was confirmed by FISH immunohistochemistry with the use of an SYT break-apart probe. The patient recovered satisfactorily, but at follow-up 5 years and 4 months later, tumoral activity was evident in the left side of the neck. A biopsy found that 5 lymph nodes contained a metastasis of the synovial sarcoma. Again, a bilateral neck dissection was performed, and it revealed that 16 of 16 right-side nodes and 36 of 36 left-side nodes were negative. Two months later, the patient received 46 Gy of radiotherapy in 23 sessions. She remained free of disease during 2 more years of follow-up. Synovial sarcoma of the larynx is a rare entity. Organ preservation seems to be indicated in these cases. The histologic diagnosis may be difficult. In this case, the identification of a genetic mutation corroborated the diagnosis.

Central odontogenic fibroma: new findings and report of a multicentric collaborative study.

OBJECTIVE: The aim of this study was to describe the clinicopathologic and immunohistochemical characteristics of 14 cases of central odontogenic fibroma (COF), and the ultrastructural features of 2 of them. STUDY DESIGN: Collaborative retrospective study based on the records of 4 oral pathology diagnostic services in Latin America based on the current World Health Organization classification. RESULTS: There were 7 male and 7 female patients (mean age 31.8 years). Eight tumors occurred in the maxilla and 6 in the mandible. Thirteen cases were epithelium-rich and 1 epithelium-poor COF. Three were classified as hybrid COF with giant cell lesion. Mean size of the hybrid lesions were larger than pure COF (3.8 vs. 2.4 cm). Odontogenic epithelial islands were immunoreactive for cytokeratin (CK) AE1/AE3, CK5, CK14, CK19, and 34BE12 and negative for CK1 and CK18. Langerhans cells positive for S-100 and CD1a were found within the epithelial islands in 6/6 tested cases. CD68 was expressed in the giant cells of the hybrid lesions and in a few mononuclear cells of 2 cases of COF. Ki-67 index was <1% in all cases. In 6 tumors (42.8%), there were small globular eosinophilic droplets within the epithelial islands, which were positive for collagen type IV, and 9/13 cases (69.2%) were focally positive for smooth muscle actin. In addition to fibroblasts, myofibroblastic differentiation was found in the 2 cases studied ultrastructurally. CONCLUSIONS: Immunohistochemistry was useful to confirm the presence of epithelium and to exclude other central fibrous tumors. COF also contains a variable number of mast cells, Langerhans cells, and myofibroblasts, and further studies are needed to better understand the participation of these cells in COF histogenesis.

Siringoma condroide en el labio superior: reporte de un caso / Chondroid syringoma of the upper lip: report of a case

Paciente masculino de 81 años de edad que acudió a consulta con un cirujano dentista por presentar una lesión nodular, asintomática, firme y móvil en el labio superior del lado derecho. El sujeto refi rió tener la lesión desde la infancia, pero notó crecimiento lento en el último año. El diagnóstico clínico indicaba un adenoma pleomorfo, por lo que el individuo se sometió a biopsia escisional bajo anestesia local. El espécimen se envió a estudio histopatológico. La evolución del paciente fue satisfactoria, sin reincidencia de la lesión. El examen microscópico reveló la presencia de una neoplasia bien delimitada constituida pormúltiples estructuras ductales pequeñas en la dermis. Estos ductos se encontraban revestidos por dos hileras de células epiteliales planas y contenían cantidades variables de material amorfo en la luz. El estroma presentaba diferenciación condroide.

An 81-year-old male patient consulted a dental surgeon due to his presenting a fi rm, mobile, asymptomatic nodular lesion on the upper lip. The patient stated that he had had the mass since childhood but that it had grown slowly over the course of the previous year. The clinical diagnosis was pleomorphic adenoma, for which reason the patient underwent an excisional biopsy under local anesthesia. The specimen was sent for histopathological examination. The patient’s progress was satisfactory and there was no recurrence of the lesion. Micro-scopic examination revealed the presence of a well-defi ned neoplasm consisting of multiple small ductal structures located in the dermis. These ducts were lined with two rows of fl attened epithelial cells and contained varying amounts of amorphous material in the lumen. The stroma exhibited chondroid differentiation.

Carotid body tumour resection with LigaSure device.

OBJECTIVE: We carried out this study in patients who underwent resection of carotid body tumour (CBT). Shamblin's classification system was used as well as the modified Shamblin classification. We sought to determine whether surgical time and bleeding could be reduced with the use of the LigaSure system. METHODS: A prospective study was carried out in patients with CBT. RESULTS: A decrease in both time and bleeding was shown, although only overall time showed statistical significance. Cases were classified as Shamblin I, II and III in two, six, and four cases, respectively, and after surgical treatment were classified as modified Shamblin I, II, IIIa and IIIb in two, one, and six cases, respectively, by infiltration to the carotid. There was nerve damage in four cases, and there were three carotid resections. CONCLUSIONS: Use of LigaSure decreased bleeding and surgical time in CBTs. Lesions of the artery are mainly caused by infiltration or by muscular hypotrophy of the artery, which frequently requires vascular reconstruction. Nerve injury continues to be an important postoperative complication, which may result in a reduction in the quality of life for the patient. The rates of nerve injury as a result of surgery were unchanged.