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(1/88) The pterygopalatine fossa: postoperative MR imaging appearance.

BACKGROUND AND PURPOSE: The pterygopalatine fossa (PPF) is an important anatomic location of the deep portion of the face. It is essential to review this area on both pre- and posttreatment studies of head and neck malignancies to assess local extent of disease or recurrence and perineural tumor spread. The purpose of this study was to review the postoperative appearance of the PPF on MR images. METHODS: Imaging and clinical data of 10 patients who underwent surgical resection of tumor in which the PPF was violated at surgery were reviewed. Patients were included in the study if there was no imaging or clinical evidence of tumor in the PPF pre- or postoperatively. Postoperative MR studies were examined to assess the appearance of the PPF. RESULTS: The PPF is consistently and persistently abnormal after surgical violation. There is loss of the normal T1 signal hyperintensity and abnormal, increased contrast enhancement, as seen on fat-suppressed T1-weighted images. These postoperative changes are strikingly similar to those of tumor involvement. CONCLUSION: After surgical violation, the PPF will always appear abnormal on MR images, and the expected imaging findings must be recognized to avoid the misdiagnosis of tumor recurrence.  (+info)

(2/88) Gamma-rays enhance rAAV-mediated transgene expression and cytocidal effect of AAV-HSVtk/ganciclovir on cancer cells.

Adeno-associated virus (AAV) vector has several unique properties suited for gene therapy applications. However, relatively low efficiency of transgene expression, which is mainly due to a limited second-strand synthesis from the single-stranded AAV genome, can be a problem in some applications that require potent gene expression such as antitumor applications. Recently, gamma-ray irradiation has been reported to enhance the second-strand synthesis of the AAV genome, and consequently transgene expression. We demonstrate here that an AAV vector harboring the herpes simplex virus type-1 thymidine kinase (HSVtk) is able to kill cancer cells more efficiently when used in combination with gamma-ray irradiation. A human maxillary sinus cancer cell line, NKO-1, was efficiently killed in combination with HSVtk transduction and ganciclovir (GCV), as expected. More importantly, gamma-ray irradiation of practical dosages augmented the cytocidal effect of the HSVtk/GCV system. Southern analysis indicated that gamma-rays enhanced the double-strand synthesis of the rAAV genome in NKO-1 cells. These findings suggest that the combination of rAAVtk/GCV suicide gene therapy with radiotherapy has synergistic effects in the treatment of cancers and may lead to a reduction of the potential toxicity of both rAAVtk/GCV and gamma-ray irradiation.  (+info)

(3/88) Influence of postsurgical residual tumor volume on local control in radiotherapy for maxillary sinus cancer.

BACKGROUND: The aim was to study the influence of postsurgical gross residual tumor volume on local control of maxillary sinus cancer treated with radiotherapy combined with debulking surgery. METHODS: Forty-three patients who underwent combined surgery and radiotherapy (50-72 Gy, median 60 Gy) for squamous cell carcinoma of the maxillary sinus were reviewed. Gross residual tumor volume (GRTV) after surgery was measured on computed tomograms obtained during the radiotherapy planning. Patients were classified according to GRTV as follows: group AA, GRTV = 0 (microscopic residual, n = 2); group A, GRTV < 10 cm3 (n = 24); group B, 10-40 cm3 (n = 9); and group C, > or = 40 cm3 (n = 8). The relationship between local control and GRTV was analyzed using univariate and multivariate analysis. RESULTS: The 2-year local control rate for all patients was 62%. The differences in local control rates between groups AA, A and B were not significant (P > 0.05), but the rate was significantly lower in group C than in the other groups (69% at 2 years vs 31% at 1 year, P < 0.001). Multivariate analysis showed that GRTV (P = 0.002) and histological differentiation (poorly differentiated histology was favorable, P = 0.035) were independent prognostic factors and that intra-arterial chemotherapy and administered total dose were not. Local control in groups A and B significantly depended on the total dose of radiotherapy, with 2-year control rates of patients receiving 50 Gy (n = 6) and > or = 60 Gy (n = 27) of 17% vs 79%, respectively (P < 0.001). CONCLUSIONS: Our data suggest that adequate, not complete, debulking associated with a total radiotherapy dose of > or = 60 Gy can provide satisfactory local control for patients with squamous cell carcinoma of the maxillary sinus.  (+info)

(4/88) Results of multimodality therapy for squamous cell carcinoma of maxillary sinus.

BACKGROUND: A wide variety of modalities, including surgery, radiation therapy, and chemotherapy, alone or in combination, have been used for the treatment of squamous cell carcinoma (SCC) of the maxillary sinus to obtain better local control and maintain functions. However, there is still much controversy with regard to the optimum treatment. METHODS: From 1987 to 1999, 33 patients with SCC of maxillary sinus were treated at the Department of Otolaryngology-Head and Neck Surgery, University of Tokyo Hospital. The treatment consisted of 30-40 grays (Gy) of preoperative radiotherapy with concomitant intraarterial infusion of 5-fluorouracil and cisplatin followed by surgery and 30-40 Gy of postoperative radiotherapy, for tumors without skull base invasion. For tumors invading the skull base, preoperative systemic chemotherapy with or without radiotherapy was performed, instead of intraarterial chemotherapy, then followed by skull base surgery. The surgical procedures varied according to the extent of tumor. Results were compared with those of the 108 patients treated in our hospital from 1976 to 1982. RESULTS: Partial maxillectomy was performed in 2 T2 patients and 12 T3 patients. Total maxillectomy was performed in 1 T2 patient, 3 T2 patients, and 7 T4 patients. Skull base surgery was performed in eight T4 patients. Orbital content and hard palate were preserved in 22 patients and 18 patients, respectively. The overall 5-year survival rates were 86% in T 3 patients and 67 % in T4 patients, respectively. CONCLUSIONS: Our multimodal treatment has provided favorable local control and survival outcome with good functional results.  (+info)

(5/88) Prognostic value of p53 mutations, bax, and spontaneous apoptosis in maxillary sinus squamous cell carcinoma.

BACKGROUND: Many researchers have attempted to correlate p53 mutation and spontaneous apoptosis with the effectiveness of radiochemotherapy and with prognosis in several malignancies. METHODS: The current study group consisted of 70 Japanese patients with maxillary sinus squamous cell carcinoma (SCC). Fifty seven patients were treated with radiochemotherapy followed by total or partial maxillectomy, and the remaining 13 patients were treated with radiotherapy alone. Tumor biopsy specimens at pretreatment status were examined for apoptosis-related proteins such as p53 protein, Fas, bax, bcl-x, and apoptosis using immunohistologic methods. The proportion of apoptotic cells labeled by single stranded DNA antibody was expressed as an apoptotic index (AI). p53 mutations at exons 5 through 8 were analyzed by direct sequence on polymerase chain reaction amplified products obtained from laser microdissected tissues. The effectiveness of radiochemotherapy was investigated histologically on surgically dissected specimens. RESULTS: p53 mutations were identified in 20 (29%) of 70 patients. p53 protein was overexpressed in 39 patients (56%), Fas in 20 patients (29%), bax in 40 patients (57%), and bcl-x in 33 patients (47%). Overexpression of bax was associated with negativity of bcl-x (P = 0.015) and with high AI (P = 0.024). Low AI and/or p53 mutation in the pretreatment tissues correlated with low histologic effectiveness of radiochemotherapy (P = 0.048, P = 0.019, respectively). Kaplan-Meier analysis as well as univariate analysis using the Cox proportional hazards model showed that low histologic effectiveness of radiochemotherapy (P = 0.0281, P = 0.0284, respectively), p53 mutations (P = 0.0095, P = 0.0187, respectively), negativity of bax (P = 0.0069, P = 0.0191, respectively), and low AI (P = 0.0134, P = 0.0407, respectively) were significantly related to worse disease-free survival. Multivariate analysis showed AI as an independent factor predicting for disease-free survival (P = 0.0455). CONCLUSIONS: The p53 mutations, expression of bax, and levels of spontaneous apoptosis have prognostic value in maxillary sinus SCC; AI especially is an independent factor for disease-free survival. A high level of spontaneous apoptosis induced by overexpression of bax may increase sensitivity of radiochemotherapy resulting in good prognosis, while p53 mutation may lead to resistance against radiochemotherapy, resulting in poor prognosis.  (+info)

(6/88) Bimaxillary chondrosarcoma: clinical, radiologic, and histologic correlation.

In this report, we describe an unusual case of chondrosarcoma that involved the entire bimaxillary and nasal skeleton. The pathogenesis, correlation of histopathology with radiology, and management of chondrosarcoma are reviewed.  (+info)

(7/88) Fine-needle aspiration biopsy cytology of malignant neoplasms of the sinonasal tract.

BACKGROUND: Primary and metastatic malignancies that originate in the sinonasal tract are rare and histologically diverse. The role of fine-needle aspiration biopsy (FNAB) and the cytomorphologic features of these tumors have not been specifically addressed. METHODS: The authors reviewed 22 cytology cases (20 FNABs, 1 sputum sample, and 1 pleural fluid sample) from 18 patients with malignancies originating in the sinonasal tract (17 carcinomas, 3 melanomas, and 2 sarcomas) and assessed the cytomorphology, cytohistologic correlation, and ability of cytology to render a specific diagnosis. RESULTS: Primary and metastastic sites sampled by FNAB included masses in or around the nose (n = 2), orbit (2), maxillary sinus (2), frontal sinus (1), intraoral area (1), preauricular area (1), soft tissue neck masses, parotid and lymph nodes (10), and cervical spine (1). Exfoliative cytology was positive in two samples of sputum and pleural fluid, representing the initial cancer diagnosis before the sinonasal primary tumor was detected. Seventeen of 22 (77.3%) cases were classified as carcinoma not otherwise specified, carcinoma with specific differentiation, sarcoma, or melanoma. Cytology failed to correctly classify the specific subtype of three carcinomas. The cytologic features that were evaluated included cellularity, cellular arrangement, nuclear features, nuclear-to-cytoplasmic ratio, and the background appearance. CONCLUSIONS: Sinonasal tract malignancies demonstrate a wide range of cytologic findings but specific features allowing for an accurate and definitive diagnosis are often present in many tumors. Fine-needle aspiration cytology is an important diagnostic tool in the management of sinonasal malignancies and can be complemented by the use of ancillary studies for the diagnosis of poorly differentiated or nonepithelial tumors.  (+info)

(8/88) Recurrent desmoplastic ameloblastoma of the maxilla: a case report.

A case of desmoplastic ameloblastoma recurring within 2 months of curettage is presented. This tumour appeared in the premolar region of the left maxilla with involvement of the antrum. The 24-year-old female patient was initially treated by curettage with wide surgical margins. Later, partial maxillectomy was carried out followed immediately by iliac bone graft. The case was followed with periodic plain radiography and computed tomography. The presence of a pulpally infected premolar and the atypical radiographic appearance obscured the disease. The biologic profile of this tumour is not fully understood because of the limited number of reported cases, coupled with inadequate long-term follow-up. A review of the lesion with emphasis on the pathogenesis of recurrence is discussed.  (+info)