A rare cause of persistent atelectasis in childhood: mucoepidermoid carcinoma

A 12-year-old boy presented to our clinic with recurrent lower respiratory tract symptoms that are wheezing, cough, bronchopneumonia, and fever and with a diagnosis of bacterial endocarditis. Physical examination revealed that breath sounds diminished in the left lower lobe. Because cardiac sounds and echocardiography were normal bacterial endocarditis was excluded. Chest radiograph and computerized tomography scan showed a left lower lobe atelectasis and consolidation. Despite medical therapy including antibiotics, bronchodilator etc, atelectasis persisted. Fiberoptic flexible bronchoscopy (FFB) revealed a tumor that totally obstructed the left lower lobe bronchus. Open lung biopsy revealed a low-grade mucoepidermoid carcinoma. Left lower lung lobectomy was performed. The patient is in good condition 12 months after the operation. We proposed that FFB should be performed earlier in patients with recurrent lower respiratory symptoms who have persistent atelectasis or unifocal infiltration.

CK7+/CK20- immunoexpression profile is typical of salivary gland neoplasia

AIMS

To evaluate cytokeratin (CK) 7/20 expression patterns in salivary gland neoplasia.

METHODS AND RESULTS

Formalin-fixed paraffin embedded tissue from 153 salivary gland tumours were evaluated for CK7/20 immunoreactivity. The tumours included pleomorphic adenoma (n = 24), myoepithelioma (n = 9), papillary cystadenoma (n = 3), oncocytoma (n = 2), adenoid cystic carcinoma (n = 22), mucoepidermoid carcinoma (n = 21), polymorphous low-grade adenocarcinoma (n = 21), carcinoma ex-pleomorphic adenoma (n = 11), acinic cell carcinoma (n = 17), epimyoepithelial carcinoma (n = 7), oncocytic carcinoma (n = 3), hyalinizing clear cell carcinoma (n = 1), papillary cystadenocarcinoma (n = 1), salivary duct carcinoma (n = 3), adenocarcinoma (not otherwise specified) (n = 4) and squamous carcinoma (n = 4). Immunohistochemical procedures were performed using monoclonal antibodies CK7 (OV-TL 12/30), CK20 (Ks 20.8) and M3515 cytokeratin (AE1/AE3) in the presence of appropriate controls. The results were expressed semiquantitatively, according to the estimated percentage of positive tumour cells: 1+, 5-25%; 2+, 26-75%; and 3+, 76-100%. All salivary gland neoplasms showed a CK7+/CK20- immunoprofile ranging from 5 to 100%. Squamous carcinoma showed negative CK7/20 immunoexpression.

CONCLUSIONS

Although the CK7/20 immunoprofile is not useful in distinguishing the various types of salivary gland neoplasms or between benign and malignant salivary gland tumours, it may facilitate differentiation of primary salivary gland neoplasia from metastatic tumours and squamous carcinoma, and the diagnosis of metastatic salivary gland tumours.

Necrotizing sialometaplasia versus invasive carcinoma of the head and neck: the use of myoepithelial markers and keratin subtypes as an adjunct to diagnosis

AIMS

To investigate the use of immunohistochemistry in distinguishing necrotizing sialometaplasia (NSM) from squamous cell (SCC) and mucoepidermoid carcinoma (MEC) by (i) the identification of myoepithelial cells and (ii) cytokeratin (CK) expression.

METHODS AND RESULTS

Thirteen cases with the histological changes of NSM, eight SCCs and eight MECs were examined with the following immunohistochemical markers: calponin, S100, smooth muscle actin (SMA), p63, CK7, CK5, CK6 and CAM5.2. The distribution and intensity of staining were recorded. Residual myoepithelial cells (best demonstrated by calponin and SMA) were identified at the periphery of the epithelial islands in all cases of NSM (although not in all islands), in contrast to MEC and SCC. S100 showed a similar pattern, although staining fewer cells. Moderate rather than extensive expression of CK7 may help to distinguish NSM from MEC.

CONCLUSION

Identification of myoepithelial cells and CK7 expression may help to distinguish NSM from its mimics.

F-18 FDG PET/CT imaging of low-grade mucoepidermoid carcinoma of the bronchus

Mucoepidermoid carcinomas in the bronchial tree are extremely rare tumors. Such tumors are classified into low-grade and high-grade on the basis of histological criteria. Fluorine-18-fluorodeoxyglucose positron emission tomography (F-18 FDG PET) is a useful technique for the evaluation of pulmonary lesions; however, to our knowledge, F-18 FDG PET findings in mucoepidermoid carcinoma of the bronchus have been described in only a few cases. Identifiable focal F-18 FDG uptake has been reported in high-grade mucoepidermoid carcinoma, but it is unclear whether F-18 FDG accumulates in low-grade mucoepidermoid carcinoma. Here, we present the case of a 37-year-old woman, with pathologically proven low-grade mucoepidermoid carcinoma, who underwent high-resolution computed tomography (CT) and F-18 FDG PET/CT before treatment.

Mucoepidermoid carcinoma of lung: a case report

Mucoepidermoid lung tumours are uncommon neoplasms comprising of 0.2% of all the lung tumours and historically included under the term bronchial adenomas. This is a case report of a bronchial tumour in the hilar region present since 3 years. The neoplasm could be easily classified as a mucoepidermoid tumour of low malignant potential, as it resembled the histologically identical lesion in the main salivary glands. The case is reported for its rarity and for the histological evaluation of the malignant potential in an apparently clinically benign neoplasm.

Oncocytic variant of mucoepidermoid carcinoma of submandibular gland: an unusual clinical and morphological entity

In this case report we describe a rare tumor--Oncocytic variant of Mucoepidermoid carcinoma of the submandibular salivary gland with a review of the literature. Oncocytic metaplasia in salivary glands is a benign change that is associated with increasing age and also seen in a few salivary gland neoplasms', which include oncocytoma, Warthin's tumor, and the rare, oncocytic carcinoma. Oncocytic differentiation in mucoepidermoid carcinoma (MEC) is uncommon. Only twelve well-documented cases of oncocytic MEC have been reported previously all of which occurred in the parotid gland. To the best of our knowledge this is the first case of oncocytic mucoepidermoid carcinoma involving the submandibular salivary gland. The recognition of this entity is important, since most of the other primary oncocytic lesions of the salivary gland are benign.

[Mucoepidermoid carcinoma of the parotid gland as a secondary malignancy developed ten years after chemotherapy for childhood acute lymphoblastic leukemia]

We report on a case of mucoepidermoid carcinoma of the parotid gland following treatment of acute lymphoblastic leukemia (ALL) in childhood. The female patient was diagnosed as having T-cell ALL at the age of 13 years. Treatment included multidrug chemotherapy and prophylactic 18 Gy cranial irradiation. She developed low-grade mucoepidermoid carcinoma of the right parotid gland at the age of 24 years, the most probable cause of the secondary malignancy being radiation. In a literature review of mucoepidermoid carcinoma following ALL, 11 out of 14 cases received radiation therapy for the initial treatment of ALL, but 3 cases had no radiation therapy. The parotid gland carcinoma as a secondary malignancy following ALL in childhood is rare, but it highlights the need for concern about the secondary malignancy in patients with painless parotid swelling after chemoradiotherapy.

Mucoepidermoid carcinoma arising in Warthin's tumor: a case report

Malignant transformation of the epithelial component of Warthin's tumor is extremely rare. We describe our experience of mucoepidermoid carcinoma arising in Warthin's tumor of the parotid gland in a 35 year old female. The tumor removed from the parotid region was well encapsulated and histologically comprised ofmucoepidermoid carcinoma along with areas of Warthin's tumor. The pathogenesis and differential diagnosis of this rare occurrence have been discussed.

Mucoepidermoid carcinoma of the external auditory canal (EAC)

We present the third case of mucoepidermoid carcinoma of the external auditory canal (EAC) in the English literature, and discuss the management of this lesion. The patient underwent a wide local resection, superficial parotidectomy, and selective neck dissection. Although intraoperative frozen section margins were negative, permanent histopathologic examination demonstrated tumor in the medial margin, and the tumor was upgraded to a high-grade mucoepidermoid carcinoma. The patient returned to the operating room for a wider local resection, and EAC reconstruction with a temporoparietal pedicled flap and split thickness skin graft. All margins were negative on final histopathologic examination. Radiotherapy was deferred in the event of a recurrence. The patient is currently disease-free 29 months after the final excision. Most authors advocate an aggressive surgical approach, which includes a form of a temporal bone resection, for the treatment of EAC carcinoma. Although this may be warranted in cases of squamous cell carcinoma, mucoepidermoid carcinoma of the EAC may be amenable to a conservative step-by-step approach for local control with less postoperative morbidity. Given the difficulty in detecting mucoepidermoid carcinoma in surgical margins by frozen section analysis, patients should be informed of the possibility of further surgery (re-resection) when a conservative approach is used.

[Prognosis of mucoepidermoid carcinoma of the bronchi]

BACKGROUND

Mucoepidermoid cancer is exceptional in the respiratory tract, accounting for only 0.2% of primary lung cancers.

CASE REPORTS

We report three cases of mucoepidermoid carcinoma. The inaugural signs were hemoptysia in a 10-year-old child, recurrent lower respiratory tract infections in a 13-year-old child, and dyspnea with chest pain in a 32-year-old adult. Bronchial fibroscopy disclosed a proximal endobronchial tumor in all three patients. Pathology study of the operative specimen identified low-grade malignant mucoepidermoid carcinoma in the two children and high-grade malignant mucoepidermoid carcinoma in the adult. Surgical resection was performed for the pediatric cases. Outcome was favorable with recurrence-free survival at eight years in the first child. The surgical resection was less radical in the second child due to locoregional extension. This child was lost to follow-up. The clinical course was rapidly fatal in the third patient who presented metastatic spread at diagnosis and died one month later.

DISCUSSION

The prognosis of mucoepidermoid tumors of the bronchi is closely related to tumor grade and extension at diagnosis. Unlike high-grade mucoepidermoid carcinoma, the progression of low-grade tumors, which predominate in children, is generally slow, enabling good prognosis if diagnosis is established early. Early search for these tumors in patients presenting chronic or recurrent respiratory manifestations would avoid late diagnosis and improve prognosis.

[Sensitivity and specificity of fine needle aspiration biopsy in parotid masses]

OBJECTIVES

We aimed to determine the sensitivity and specificity of fine needle aspiration biopsy (FNAB) in patients with parotid masses.

PATIENTS AND METHODS

The study included 29 patients (15 males, 14 females; mean age 52 years; range 20 to 83 years) who underwent FNAB and parotidectomy for parotid masses. After a detailed history taking, otorhinolaryngologic and systemic examinations were performed. Neck ultrasonography and, when needed, neck computed tomography were used. Superficial parotidectomy was performed in 20 patients and total parotidectomy in nine patients.

RESULTS

The results of FNAB were reported as benign in 21 patients (72.4%), malignant in six patients (20.7%), and suspicious in two patients (6.9%). Postoperative histopathologic diagnoses were reported as benign in 17 patients (58.6%) and malignant in 12 patients (41.4%). The sensitivity and specificity rates for FNAB were 54.6% and 100%, respectively. The most common histopathological diagnosis was pleomorphic adenoma (n=7, 24.1%), followed by mucoepidermoid carcinoma (n=4, 13.8%), and Warthin's tumor (n=3, 10.3%).

CONCLUSION

Preoperative FNAB for parotid masses plays an important role in planning surgery.

[Mucoepidermoid carcinoma of parotid and submandibular glands: diagnostics and treatment]

Data were presented about 48 patients with mucoepidermoid carcinoma (MEC) of parotid gland and 4 patients with MEC of submandibular gland. Peculiarities of MEC clinical course depending upon differentiation stage of tumor cells, its localization etc. were noted. Diagnostic value of a number of additional analyses (cytologic, ultrasonic study, X-ray and others) was appreciated. Possibility of preserving facial nerve without any detriment for treatment efficacy in a number of cases was verified. In conditions of thorough checkup and dispensary observation of the patients it was often possible to refrain from preventive interventions on neck lymphatic apparatus.

Salivary gland neoplasms in children: the experience of the Istituto Nazionale Tumori of Milan

BACKGROUND

Epithelial salivary gland tumors are very uncommon in pediatric age. We report a series of 52 cases treated at the Istituto Nazionale Tumori of Milan, Italy, over a 30-year period. These results are presented in conjunction with a literature review of salivary tumors with a view to providing an up-to-date overview of the clinical course, prognosis, and treatment options for this rare tumor.

PROCEDURE

Fifty-two cases of epithelial salivary tumors were reviewed and the clinical-pathological information concerning tumor characteristics, therapy, and follow-up were collected. Patients' age ranged between 4 and 18 years.

RESULTS

The major salivary glands were the main site of tumor occurrence (79% of cases arose in parotid glands); 37 patients had benign tumors (pleomorphic adenoma), 15 had malignant tumors (12 mucoepidermoid carcinoma, 9 low grade). All the patients were treated by surgery; local relapses after parotidectomy were 4% and 25%, in benign and malignant tumors, respectively. When tumor enucleation was performed, recurrences occurred in 50% of benign neoplasms. At the time of the report, all patients with benign tumors were alive, 35(95%) without evidence of disease; only one patient with malignant tumor died of disease.

CONCLUSIONS

Epithelial salivary glands tumor in children had different characteristics compared with their adult counterpart with respect to the frequency of histotypes and site of occurrence, but their prognosis seems to be similar. Parotidectomy (total or superficial) is the best choice for achieving good cure rates in both benign and malignant tumors.

18F-FDG PET/CT of thymic epithelial tumors: usefulness for distinguishing and staging tumor subgroups

The purpose of our study was to assess the usefulness of integrated PET/CT using 18F-FDG for distinguishing thymic epithelial tumors according to the World Health Organization (WHO) classification.

METHODS

Thirty-three patients (age range, 34-68 y; mean age, 54.6 y) with thymic epithelial tumors, who underwent both integrated PET/CT and enhanced CT, were included. The clinicopathologic stages, maximum standardized uptake values (SUVs), and uptake patterns of tumors on integrated PET/CT images, and various enhanced CT findings, are described according to the simplified (low-risk [types A, AB, and B1] and high-risk [types B2 and B3] thymomas and thymic carcinomas) subgroups of the WHO classification. Discriminant analysis was performed to determine the relative capabilities of integrated PET/CT and enhanced CT findings to differentiate tumor subgroups.

RESULTS

Tumors included 8 low-risk thymomas, 9 high-risk thymomas, and 16 thymic carcinomas. The maximum SUVs of high-risk thymomas (P < 0.001) and low-risk thymomas (P < 0.001) were found to be significantly lower than those of thymic carcinomas. Homogeneous 18F-FDG uptake within tumors was more frequently seen in thymic carcinomas than in high-risk thymomas (P = 0.027) or low-risk thymomas (P = 0.001). The uptake pattern (homogeneous vs. heterogeneous) on integrated PET/CT images and the presence of mediastinal fat invasion on enhanced CT images were found to be useful for differentiating tumor subgroups. In addition, integrated PET/CT helped detect lymph node metastases, which were not identified on enhanced CT in 2 patients.

CONCLUSION

Integrated PET/CT was found to be useful for differentiating subgroups of thymic epithelial tumors and for staging the extent of the disease.

[Primary intraosseous carcinoma of the jaws: case report and review of the literature]

Because of lacking characteristic symptoms, primary intraosseous carcinoma of the jaws can't be easily diagnosed early. A case of intraosseous mucoepidermoid carcinoma of the maxilla was reported and relevant literature was reviewed. The possible etiology, clinical symptoms, radiology, histopathology, diagnosis and treatments were discussed.

Cytokeratin profile in mucoepidermoid carcinoma is not related to its histological grading of malignancy

The objective of this experiment was to determine the relationship between the expression of cytokeratins (CKs) and histologic grading in MEC. Eleven cases of MEC were selected and graded as low, intermediate and high-grade tumors. The expression of CKs 7, 8, 10, 13 and 14 was assessed immunohistochemically using streptavidin-biotin complex method. The results showed that the studied CKs were expressed in most cases of MEC, independently of histologic grading. Nonetheless, low-grade tumors demonstrated intense staining of CK 7 and 8; additionally, CK 10 and 13 were more pronounced in this grade. The immunoexpression was variable according to cellular type and organization pattern of the tumor. Mucous cells were positive for CK 7 and 8; epidermoid cells were stained for CK 10, 13 and 14; CK 7, 8, 10 and 14 were observed in intermediate cells, and CK 7 was occasionally seen in clear cells. Cystic structures and duct-like elements in MEC were positive for CK 7 and 8, whereas solid nests showed positivity for all CKs. These results suggest that expression profile of these proteins does not reflect the biological behavior of MCE, however, it guides the detection of cellular types and differential diagnosis from other salivary gland tumors.

Primary adenoid squamous cell carcinoma of the oral cavity

Adenoid squamous cell carcinoma (ASCC) is an uncommon but well-recognized variant of squamous cell carcinoma that was first described by Lever in 1947. ASCC has been reported to originate in the sun-exposed skin of the head and neck and in other sites. An additional case of ASCC is reported here. The patient was a 64-year-old Japanese woman who requested examination of a reddish lesion on the left floor of the mouth. The biopsy material was diagnosed as squamous cell carcinoma. Clinical examination showed a well-circumscribed, 20 x 10 mm-sized lesion, which was categorized as cT2cN0cm 0. Tumor resection was therefore performed. Histologically, most parts of the lesion were conventional squamous cell carcinoma in situ, but the invasive part consisted of ASCC with gland-like or reticular appearance. The latter part was negative for mucin staining. Immunohistochemically, this lesion was positive for pancytokeratin, high-molecular-weight keratin, cytokeratin (CK) 7/8, CK19, E-cadherin and p53, but negative for vimentin, CK20, and S-100 protein. The Ki-67 labeling index was 50.3% in the ASCC part and 34.5% in the carcinoma in situ part. These findings and a review of the literature indicate that a gland-like feature of ASCC is associated with the loss of cell adhesion in the center of the cancer nests, and it can be confirmed simply by mucin staining to be neither an adenosquamous carcinoma nor ductal involvement of conventional squamous cell carcinoma.

Salivary gland tumors in survivors of childhood cancer

BACKGROUND

There is an increased incidence of second malignant neoplasms in survivors of childhood cancers. The most common second malignancies are acute leukemia, bone and soft tissue tumors, and carcinoma of the skin, breast, and thyroid. Although, ionizing radiation has been demonstrated to increase the risk of developing a salivary gland neoplasm, there are few reports of salivary gland neoplasms occurring in patients treated for cancer in childhood.

METHODS

A retrospective review of the patient registry of St. Jude Children's Research Hospital from 1963-2003.

RESULTS

Twelve survivors of childhood cancer developed a salivary gland neoplasm after completion of treatment. These patients were initially treated for a variety of childhood cancers with a combination of radiation and chemotherapy. The pathology of the salivary gland tumors were mucoepidermoid carcinoma (10), adenoid cystic carcinoma (1) , and pleomorphic adenoma (1). All patients were treated with surgical excision of the primary tumor, and postoperative radiation was added in select patients. Eleven patients were alive with no evidence of disease at last follow-up, and 1 patient was alive with clinical evidence of pulmonary metastasis.

CONCLUSION

Radiation and chemotherapy used to treat patients with childhood malignancies increases the risk of developing a second neoplasm of salivary gland origin. The majority of these neoplasms are malignant; mucoepidermoid carcinoma occurs most frequently. The treatment of these tumors includes surgical excision of the primary, with neck dissection in patients with clinical evidence of nodal metastasis, and postoperative radiation added for pathologies with adverse features.

EBM RATING

C-4.