Adenoid cystic carcinoma with myoepithelial predominance affecting maxilla and maxillary sinus.

Adenoid cystic carcinoma (ACC) represents less than 10% of all salivary gland tumors, rarely occurring centrally in the jaws. Herein we describe the case of a 36-year-old female patient presenting a painless swelling in the right maxilla, resulting in marked facial asymmetry. Intra-orally it was observed a swelling covered by an erythematous and irregular-surfaced mucosa, affecting the gingiva and crossing the midline of the hard palate. Imaging studies showed a mixed radiolucent-radiopaque lesion with ill-defined borders, involving the right side of the maxilla and the maxillary sinus. Incisional biopsy revealed basophilic cribriform tumoral islands and solid sheets of neoplastic cells invading bone trabeculae. Most of the tumoral cells presented myoepithelial characteristics, while few true luminal/epithelial cells were observed. To illustrate the epithelial-myoepithelial pattern, immunohistochemical reactions were performed, as well as double immunohistochemical staining. The diagnosis was intraosseous ACC, which features were discussed as well as the potential differential diagnosis.

Comparative histological and immunohistochemical study of ameloblastomas and ameloblastic carcinomas.

BACKGROUND: This study aimed to compare the histological and immunohistochemical characteristics of ameloblastomas (AM) and ameloblastic carcinomas (AC). MATERIAL AND METHODS: Fifteen cases of AM and 9 AC were submitted to hematoxilin and eosin (H&E) and immunohistochemical analysis with the following antibodies: cytokeratins 5,7,8,14 and 19, Ki-67, p53, p63 and the cellular adhesion molecules CD138 (Syndecan-1), E-cadherin and ß-catenin. The mean score of the expression of Ki-67 and p53 labelling index (LIs) were compared between the groups using the t test. A value of p<0.05 was considered to be statistically significant. RESULTS: All cases were positive for CKs 5, 14 and 19, but negative for CKs 7 and 8. CKs 5 and 19 were positive mainly in the central regions of the ameloblastic islands, while the expression in AC was variable in intensity and localization. CK14 was also variably expressed in both AM and AC. Ki-67 (P=.001) and p53 (P=.004) immunoexpression was higher in AC. All cases were positive for p63, but values were higher in AC. CD138 was mainly expressed in peripheral cells of AM, with a weak positivity in the central areas, while it was positive in most areas of ACs, except in less differentiated regions, where expression was decreased or lost. E-cadherin and ß-catenin were weakly positive in both AM and AC. CONCLUSIONS: These results shows that Ki-67, p53 and p63 expression was higher in AC as compared to AM, suggesting that these markers can be useful when considering diagnosis of malignancy, and perhaps could play a role in malignant transformation of AM. Pattern of expression of CKs 5 and 19 in AC were different to those found in AM, suggesting genetic alterations of these proteins in malignant cells. It was confirmed that CK19 is a good marker for benign odontogenic tumors, such as AM, but it is variably expressed in malignant cases.

Signet-ring cell change in adenoid cystic carcinoma: a clinicopathologic and immunohistochemical study of four cases.

AIMS: Signet-ring cell (SRC) change has not been reported in adenoid cystic carcinomas (ACC). This study describes the clinicopathological and immunohistochemical findings in four cases of ACC with SRCs (ACC-SRC), in which the relative proportion of the SRC component ranged from 25% to 50%. METHODS AND RESULTS: The median age was 58 years (range: 48 to 81 y) and all patients were women. The involved sites were sinonasal, lip and submandibular. Two patients developed lung metastasis and one died of disease 63 months after tumor resection. Neither mucinous nor lipid substances were detected in the SRCs. These were positive for AE1/AE3, CK14 and EMA; which highlighted the intracytoplasmic vacuole borders. The SRC nests were surrounded by α-SMA and p63 positive myoepithelial cells. When compared to the conventional component, the SRCs exhibited similar p53 positivity but lower Ki-67 and mitotic indices. SRCs were C-Myb negative. Ultrastructural examination revealed that the intracytoplasmic vacuoles were lumens lined by microvilli. CONCLUSIONS: ACC-SRC is a nonmucin and nonlipid producing phenomenon, possibly related to disturbed differentiation of ductal/luminal cells. This cellular modification in ACC apparently does not change the biological behavior of the tumor but it may cause significant diagnostic problems, particularly in incisional biopsies. © 2012 Blackwell Publishing Ltd.

Multinodular neurilemmoma of the tongue: a case report with differential immunohistochemical profile.

Neurilemmoma is a distinctive, encapsulated, benign tumor, derived from Schwann cells. It is the most common neurogenic tumor, eventually occurring in the mouth, particularly the tongue. It occurs most often during the second or third decades of life, with predilection in females. Clinically, neurilemmomas present as a solitary circumscribed nodule, rarely being multinodular. We report a case of a 46 year-old female who presented a multinodular neurilemmoma of the tongue. She had a sessile nodule with two months of evolution. The presumptive diagnosis was of a benign mesenchymal neoplasm and an excisional biopsy was performed. During the excision it was found that the lesion was formed by two well-delimitated firm yellowish-white nodules. Histopathologic evaluation revealed an encapsulated benign tissue, formed by spindle cells forming irregular Antoni A and Antoni B patterns, not easily recognizable. Immunostaining was strongly positive for S-100 protein and negative for neurofilament. The lesion was excised and after 12 months of follow-up there was no recurrence.

Central mucoepidermoid carcinoma of the mandible: report of four cases with long-term follow-up.

Central mucoepidermoid carcinomas are uncommon tumours, representing about 2 to 4% of all mucoepidermoid carcinomas. They are histologically low-grade cancers, usually affecting the mandible as uni- or multilocular radiographic lesions. The authors report four cases of central mucoepidermoid carcinomas affecting the mandible and discuss their clinical, radiographic and histological findings. Four females were affected, with a mean age of 42 years and all cases involved the posterior mandible. Treatment included surgery in three cases and surgery associated to neck dissection and radiotherapy in one case. Two patients showed no recurrence and were alive without signs of the disease after a mean follow-up of 78 months. The other two patients showed local recurrence and one was alive with disease after a follow-up of 384 months, and the other was followed-up for 324 months dying by other causes without signs of the tumour. Central mucoepidermoid carcinomas of the mandible are low-grade tumours, and effective surgical treatment involving wide local excision or en bloc resection allows patients to have a favourable prognosis after long-term follow-up.

A clinicopathologic study of 196 intraoral minor salivary gland tumours.

We present a retrospective study of 196 patients with intraoral minor salivary gland tumours, 128 malignant and 68 benign, diagnosed from 1954 to 1993 in the A. C. Camargo Hospital, São Paulo, Brazil. Sixty-five percent of the cases occurred in the palate, followed by tongue (9.7%) and retromolar area (6.1%). Pleomorphic adenoma was the most common benign tumour, and mucoepidermoid carcinoma was predominant among the malignant tumours. Surgery was the main treatment method and postoperative radiotherapy and radiotherapy alone were used in 40 and 15 patients, respectively. Local recurrence was observed in two patients with pleomorphic adenoma and in eight patients with malignant tumours. Regional lymph node metastases occurred in four cases and distant metastases in five. Forty-six of 47 patients with benign tumours who were followed up from 1 to 7 years were alive without disease. Twenty-four of 79 patients with malignant tumours who were followed up for at least 5 years died due the tumour and 47 were alive without disease.

Pemphigus vulgaris: the manifestations and long-term management of 55 patients with oral lesions.

Perhaps surprisingly, the manifestations and management of patients with pemphigus vulgaris and oral lesions have been detailed only infrequently. The present study has examined the clinical features, diagnosis and management of a cohort of 55 patients, including three adolescents, with pemphigus vulgaris predominantly affecting the oral mucosa. There was about a 6-month delay from the onset of symptoms until presentation for diagnosis, longer in men than in women. Patients typically had multiple lesions affecting mainly the buccal and/or palatal mucosae, and over half the patients had lesions affecting non-oral mucosal sites. Nearly one-quarter (24%) had cutaneous involvement. Most patients were otherwise healthy with no other autoimmune disorders. Classical histopathological features of pemphigus vulgaris were present in all patients, as well as IgG intraepithelial deposits in all patients tested and circulating epithelial antibodies in most. Thirty-two patients were treated in the clinic, four responding to topical immunosuppressive therapy, the remainder needing and responding, at least in part, to systemic immunosuppression. Systemic corticosteroids often with adjunctive immunosuppressives, particularly azathioprine, were required in 87% of patients. In 18% of the patients, the disease resolved in 3 months, but 76% had recalcitrant disease. Adverse effects were seen in 78%, and two patients died, at least one as a consequence of immunosuppressive therapy. It is concluded that pemphigus vulgaris affecting the oral mucosa is still diagnosed only after considerable delay because patients, especially men, present late; it has a chronic course; it is often associated with lesions in other mucosae and/or skin; it can be resistant to currently available therapies; and immunosuppressive therapy frequently produces adverse effects, occasionally lethal.

Oral focal acantholytic dyskeratosis induced in sialoadenectomized rats painted orally with the carcinogen 4-nitroquinoline N-oxide.

This study examines the effects of xerostomia on the development of mucosal changes proceeding carcinoma in rats painted orally with 4-nitroquinoline N-oxide (4NQO). Sialoadenectomy enhanced the incidence of focal acantholytic dyskeratosis (FAD) on the palate and tongue of rats painted on the palate with 0.5% 4NQO three times weekly. At one month, no changes were observed. After two months of painting with 4NQO, sialoadenectomized rats, but not controls, had FAD. After three months, FAD was seen in both test and control groups, but the incidence of FAD was higher in the test group and seen more on the palate than on the tongue of xerostomic animals. Neither test nor control animals developed carcinoma within this study period.

The cardiac muscle in the pulmonary vein of the rat: a morphological and electrophysiological study.

The pulmonary veins of albino Wistar rats were studied by means of light and electron microscopy. The media of larger veins consists of cardiac muscle fibers which extend until the vessels attain about 100 mu in diameter. This coat consists of external longitudinal fibers and internal circular fibers. The vasa vasorum are well developed and the capillaries show pseudofenestrations. The numerous adrenergic and cholinergic nerve endings do not form typical motor end-plates as seen in skeletal muscles. The ultrastructure of these media muscle fibers is similar to that of the rat hearts. The smooth muscle layer of larger pulmonary veins is not continuous as it is in smaller veins where it forms cushions. Comparison of albino rats and other rodents reveal striking differences. Action potential shape and propagation velocity (0.5-1.2 m/s) along the myocardial coat of the pulmonary vein were similar to those observed in the left atrium and so was their sensitivity to locally applied acetylcholine. The physiological direction of propagation in rat pulmonary veins is toward the lung. This fingind lends support to the hypothesis of a rhythmic, valve-like action of the striated musculature of the pulmonary venous wall during the systole and a possible role in the capacitance of the pulmonary circulation.