The nasopharynx is located in the upper aerodigestive tract. Its roof is formed by the basisphenoid, basiocciput and the anterior aspect of the first two cervical vertebrae, in front of the clivus. The lateral walls are formed by the margins of the superior constrictor muscle and the pharyngobasilar fascia, pharyngeal recess, torus tubarius and pharyngeal opening of auditory tube. The inferior margin of the nasopharynx is a horizontal plane passing through the hard palate and palatopharyngeal muscle. Anteriorly, it is in direct continuity with the nasal cavity through the posterior choanae. It is approximately 2.0 cm in anteroposterior diameter and about 4.0 cm in craniocaudal extent. Squamous cell carcinoma accounts for about 70% to 98% of nasopharyngeal malignant lesions found in adults. This tumor presents a high incidence in Asians, most frequently in men, and is the third most frequent cancer in women. The clinical presentation of this disease depends on the size and site of the lesion, with small-sized lesions being asymptomatic. Computed tomography and magnetic resonance imaging play essential and complementary roles in the staging and treatment of patients with nasopharyngeal cancer.

Keywords: Computed tomography, Nasopharynx, Tumor, Carcinoma

OBJECTIVE: The present study was aimed at evaluating the role of computed tomography in the local clinical staging of supraglottic tumors according to the TNM classification, as well as the interobserver agreement on the detection of the tumor extent. MATERIALS AND METHODS: Thirty-nine dossiers of inpatients of Hospital Heliópolis with supraglottic squamous cell carcinoma in the period between 1988 and 1998 were retrospectively evaluated. CT studies were individually analyzed by two radiologists. The kappa test was utilized for evaluating the interobserver agreement. RESULTS: Computed tomography has played a decisive role in the upstaging of 38.5% of cases, as a result of a deep tumor extent undetected at clinical examination. CONCLUSION: Interobserver agreement was considered as excellent for vocal folds and subglottis; good for supraglottic, paraglottic and preepiglottic spaces, thyroid and cricoid cartilages and for extralaryngeal tumor extension; and regular for the base of the tongue.

Keywords: Laryngeal neoplasms, Squamous cell carcinoma, Computed tomography, Tumors staging

The authors report a case of a two year-old girl with an extrarenal Wilms' tumor in the retroperitoneum. Abdominal plain films, intravenous urography, abdominal ultrasound and computed tomography examinations showed a retroperitoneal mass adjacent to the right kidney. The patient underwent surgery with complete resection of the mass. The diagnosis of Wilms' tumor was confirmed by histopathological study. Extrarenal Wilms' tumor is an extremely rare malignancy which is almost always presented in medical literature as a case report. The tumor may arise in the retroperitoneum, uterus and ovaries, inguinal groove, testes, skin, and even in the thorax. The exact mechanism of occurrence of this tumor in extrarenal tissues has not yet been established. The diagnosis relies on histopathological study, generally after surgical intervention.

Keywords: Extrarenal Wilms' tumor, Retroperitoneum, Radiology

Although rare, transitional cell carcinoma of the urinary tract is the second most common tumor of the kidneys. We studied retrospectively the computed tomography images of 10 patients with confirmed transitional cell carcinoma of the urinary tract. There was involvement of the bladder in 60% of the cases whereas the calyceal system and the ureters were involved in 60% and 10% of the cases, respectively. Concomitant tumors were present in 40% of the cases. The findings were sessile masses, ureteral wall thickening and renal infiltrative lesions. Calcified tumors were seen in two patients and a transitional cell tumor arising from a bladder diverticulum was identified in another patient. Local tumor dissemination was observed in 80% of the patients and distant dissemination in 20% of the patients. Computed tomography allowed the detection of local and distant tumor dissemination, thus allowing a selected group of patients to be treated conservatively.

Keywords: Transitional cell carcinoma, Computed tomography, Renal tumors

Sarcomatoid renal carcinoma is an aggressive neoplasm with clinical and radiological features similar to those of clear cell renal sarcomas. The tumor is formed by layers of malignant spindle cells that show immunohistochemical and ultrastructural characteristics of both stromal and epithelial cells, and may also contain mixoid areas of osteoclast-like giant cells, rhabdomyoblast-like pleomorphic cells as well as other rare sarcomatoid components. The authors report a case of sarcomatoid renal carcinoma in a 54-year-old male patient presenting with the classic clinical triad seen on patients with renal cell carcinomas. The typical macroscopic and microscopic features, imaging findings and differential diagnosis with true renal sarcomas are discussed.

Keywords: Renal cell carcinoma, Sarcomatoid renal carcinoma, Tumor metaplasia, Computed tomography, Ultrasonography

The authors report a case of intraabdominal desmoplastic small round cell tumor in a 21-year-old male patient who presented with abdominal pain, right lower limb thrombosis and obstructive loss of renal function. Initial investigation showed a large lobulated intraabdominal soft tissue mass with internal cystic cavities, located posteriorly to the bladder and causing obstruction of ureteral flow, compression of the right iliac vein and partial occlusion of the rectum. Involvement of intraperitoneal and retroperitoneal nodes was also seen. Ultrasound, computed tomography and magnetic resonance imaging findings, as well as surgical and histopathology macroscopical, microscopical and immunohistochemistry findings are described.

Keywords: Desmoplastic small cell tumor, Desmoplastic tumor

Undifferentiated embryonal sarcoma of the liver is a rare disease that affects predominantly children over five years of age. The most common macroscopic finding is a large hepatic mass with a greater solid component and smaller cystic areas. However, computed tomography tends to overestimate the cystic components of the lesion and consequently ultrasonography is considered a more reliable technique for evaluating the texture of the tumor. Imaging methods can help to rule out nonneoplastic diseases such as liver abscesses and hematomas, and to establish the extent of the lesions. The diagnosis of undifferentiated embryonal sarcoma can be correctly inferred when imaging findings, the age of the patient and serum alpha protein levels are concurrently analyzed. The authors report a case of undifferentiated embryonal sarcoma in a 10-year-old girl and discuss the imaging findings features and differential diagnosis.

Keywords: Sarcoma, Tumor, Liver

The authors report a rare case of granular cell tumor in the left medial rectus muscle of a seven-year-old boy. Clinical, pathologic and radiologic findings of the present case are described and a brief literature review is undertaken.

Keywords: Orbit; Granular cell tumor.

Objetivo: A principal utilidade da tomografia por emissão de pósitrons com 18-fluordeoxiglicose (FDG-PET) está no estadiamento do câncer de pulmão. Porém, ela também pode ser utilizada para diferenciar lesões pulmonares indeterminadas, mas seu impacto na ressecção cirúrgica de lesões benignas é desconhecido. O objetivo deste estudo foi comparar a prevalência de lesões benignas em toracotomias feitas por suspeição de câncer de pulmão, antes e após a introdução do FDG-PET, em um centro de referência de cirurgia torácica. Materiais e Métodos: Os autores analisaram, prospectivamente, uma base de dados cirúrgicos de todos os pacientes consecutivos submetidos a toracotomia por câncer de pulmão suspeito ou comprovado e compararam a prevalência de lesões benignas em dois grupos ao longo de dois anos consecutivos, respectivamente antes (grupo I) e depois (grupo II) da introdução da FDG-PET. Resultados: Ressecção cirúrgica foi feita em 1.233 pacientes durante o período do estudo. A prevalência de lesões benignas na cirurgia nos grupos I e II foi similar (44/626 e 41/607, ambas correspondendo a 7%), e também no grupo II, entre aqueles submetidos a FDG-PET e os restantes (21/301 e 20/306 respectivamente, ambos correspondendo a 7%). No grupo II, dos 21 pacientes com lesões benignas submetidos a FDG-PET, 19 tiveram um estudo falso-positivo (valor médio padrão de captação 5.3 [faixa 2.6–12.7]). Desses, respectivamente 13 e 4 pacientes tiveram broncoscopia não diagnóstica e biópsia transtorácica percutânea de pulmão antes da toracotomia. Não houve diferença na proporção de lesões benignas diferentes ressecadas entre o grupo I e aqueles submetidos a FDG-PET no grupo II. Conclusão: A introdução da FDG-PET não alterou a proporção de pacientes submetidos a toracotomia por lesões benignas, principalmente devido à avidez pelo isótopo de algumas lesões não malignas. Tais resultados falsos-positivos devem ser considerados nos casos em que se contempla a possibilidade de ressecção cirúrgica em pacientes com câncer de pulmão não confirmado.

Keywords: Tomografia por emissão de pósitrons; Tomografia computadorizada; Pulmão – lesões benignas ou congênitas; Câncer de pulmão – diagnóstico e estadiamento; Câncer de pulmão – cirurgia.

DWI/ADC is a completely non-invasive technique that has been successfully conducted for many years in brain imaging and is currently being studied for the assessment of other organs, such as the abdomen and pelvis and in particular the head and neck structures. Even though DWI and the ADC measurement are able provide tissue information at the cellular level, most imaging centers have not yet adopted them as part of their routine evaluation of the head and neck. DWI has demonstrated usefulness to discriminate specific histological tumor types, especially to differentiate benign solid lesions from malignant masses, to evaluate lymph nodes, particularly to differentiate benign disease from malignancy, to differentiate postradiation changes from residual tumor and potentially to predict therapy success. Moreover DWI seems to be a safer and more affordable method considering the absence of radiation and to the higher cost of FDGPET to localize tumors and to differentiate benign from malignant masses. Given all these advantages and strengths, DWI will certainly become part of the routine in the MR imaging of the head and neck.

Keywords: Head and neck; Tumors; Squamous cell carcinoma; Diffusion weighted imaging; Apparent diffusion coefficient map; Exponential diffusion weighted imaging.

Inflammatory myofibroblastic tumors rarely affect the urinary tract or children, and frequently mimic malignancy on imaging studies. According to the recent literature, only 35 cases of such bladder tumors in children have been reported. The authors present the case of a child with a bladder myofibroblastic tumor with favorable progression following complete surgical resection.

Keywords: Bladder tumor; Inflammatory myofibroblastic tumor; Computed tomography.

OBJETIVO: Avaliar a completude das fissuras, resposta radiológica ao tratamento e análise quantitativa por TC (AQTC) em população de pacientes com enfisema grave submetidos ao implante de valvas endobrônquicas (VEB). MATERIAIS E MÉTODOS: Foram estudados exames de TC multidetectores de 29 pacientes, realizados com protocolo de baixo dose, cortes finos, sem contraste. Dois radiologistas revisaram, retrospectivamente, os exames em consenso. A completude das fissuras foi estimada em escala de 5% e a resposta radiológica (atelectasia/perda volumétrica do lobo alvo) foi avaliada. AQTC foi realizada nos exames pré e pós-tratamento utilizando programa completamente automático. RESULTADOS: Resposta radiológica positiva foi vista em 16/29 pacientes. Os 13 pacientes sem resposta à TC apresentavam fissuras incompletas e completude média das fissuras obliquas de 72,8%, contra 88,3% no outro grupo. Os resultados mais significativos da AQTC mostraram redução do volume pulmonar (VP) total (média de 542 ml), VP tratado (700 ml) e volume de enfisema (331,4 ml) no grupo com resposta positiva, que também apresentou melhora nos testes funcionais. CONCLUSÃO: O benefício das VEB é maior em pacientes com fissuras completas e que desenvolvem atelectasia lobar. Nos pacientes sem resposta radiológica encontramos maior prevalência de fissuras incompletas e grau de incompletude das fissuras. Nossa AQTC automática detectou as alterações pós-tratamento, principalmente considerado a análise do pulmão tratado.

Keywords: Enfisema; Terapia de colapso pulmonar; Tomografia computadorizada.

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors with distinct morphological and biological manifestations, the liver being the main organ affected by its metastases. However, primary hepatic involvement is quite rare. Hepatic NENs can have a variety of radiological presentation forms and can therefore mimic other lesions, making their diagnosis challenging. Nonetheless, certain imaging aspects allow NENs to be included among the main differential diagnoses of hepatic lesions and can guide the search for an extrahepatic primary site when the probable diagnosis is metastases.

Keywords: Carcinoma, neuroendocrine; Neuroendocrine tumors; Neoplasm metastasis; Liver.

Objective: To determine whether the whole-body tumor burden, as quantified by ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT), is a prognostic indicator in advanced (stage III or IV) non-small cell lung cancer (NSCLC). Materials and Methods: This was a prospective study in which we evaluated ¹⁸F-FDG PET/CT staging parameters to quantify tumor burdens in patients with stage III or IV NSCLC. The following parameters were evaluated for the whole body (including the primary tumor) and for the primary tumor alone, respectively: maximum standardized uptake volume (wbSUV_max and tuSUV_max); metabolic tumor volume (wbMTV and tuMTV); and total lesion glycolysis (wbTLG and tuTLG). To determine whether the ¹⁸F-FDG PET/CT parameters were associated with overall survival (OS) and progression-free survival (PFS), we evaluated the wbSUV_max/tuSUV_max, wbMTV/tuMTV, and wbTLG/tuTLG ratios. Results: ¹⁸F-FDG PET/CT was performed for staging in 52 patients who were followed for a median of 11.0 months (mean, 11.7 months). The estimated median PFS and OS were 9.6 months and 11.6 months, respectively. In the univariate analysis, OS was found to correlate significantly with wbTLG (hazard ratio [HR] = 1.001; 95% confidence interval [95 CI]: 1.000–1.001; p = 0.0361) and with the wbTLG/tuTLG ratio (HR = 1.705; 95% CI: 1.232–2.362; p = 0.0013). In the multivariate analysis, only the wbTLG/tuTLG ratio was independently associated with OS (HR = 1.660; 95% CI: 1.193–2.310; p = 0.0027). Conclusion: The wbTLG/tuTLG ratio is an independent prognostic indicator of OS in advanced-stage NSCLC.

Keywords: Fluorodeoxyglucose F18; Positron-emission tomography/methods; Tomography, X-ray computed/methods; Carcinoma, non-small-cell lung/diagnosis; Tumor burden; Carcinoma, non-small-cell lung/mortality.

OBJETIVO: Avaliar os padrões tomográficos relacionados aos agentes etiológicos da pneumonia em pacientes durante o primeiro ano após transplante renal. MATERIAIS E MÉTODOS: Foram analisados dados de prontuários de 956 pacientes submetidos a transplante renal, no período de 2013 a 2018, em um centro transplantador renal do nordeste do Brasil. Nos pacientes que desenvolveram pneumonia, os agentes etiológicos foram classificados em bactérias piogênicas, micobactérias, fungos, vírus e pneumonia polimicrobiana, enquanto os padrões tomográficos foram classificados em consolidação, broncopneumonia, pneumonia intersticial e nódulos e massas. Para verificar associação estatística entre micro-organismos e padrões tomográficos, foi utilizado o teste exato de Fisher, com p < 0,001. RESULTADOS: Foram encontrados 101 casos de pneumonia, dos quais 60 (59,4%) tiveram agente etiológico identificado, sendo as bactérias piogênicas as mais frequentes, detectadas em 22 (36,7%) dos casos. Entre os pacientes com agente causal identificado, o padrão tomográfico predominante foi o de nódulos e massas, identificado em 25 (41,7%) casos. Foi observada associação entre bactérias piogênicas e o padrão de consolidação, fungos com nódulos e massas, bem como entre agentes virais e padrão intersticial. CONCLUSÃO: Foi demonstrada associação estatística entre micro-organismos causadores de pneumonia e padrões tomográficos, informação que pode contribuir para o planejamento da terapia de pacientes transplantados renais.

Keywords: Pneumonia; Transplante de rim; Tomografia computadorizada.