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: To evaluate the role, especially of computed tomography, in the staging of maxillary sinus carcinomas. MATERIALS AND METHODS: Ten cases of carcinoma treated in Hospital Heliópolis Department of Diagnostic Imaging and Head and Neck Surgery, São Paulo, SP, Brazil, in the period between 1988 and 2002, were evaluated. RESULTS: Nine patients presented with tumor extension to the cheek, eight to the masticator space, seven to the mouth floor and hard palate, five to the pterygoid fossa, five to the orbit, three to the ethmoid bone, and one to the skull base. Three of the patients were staged T3, and seven T4. Two patients had lymph nodes metastases at their initial presentation, and were staged T4. All of the cases were histopathologically confirmed. CONCLUSION: The accurate analysis of the tumor local extent and dissemination by means of computed tomography and magnetic resonance imaging plays a relevant role in the surgical planning, besides influencing the therapeutic conduct and prognosis.

Keywords: Squamous cell carcinoma, X-ray tomography, Cancer, Maxillary sinus

OBJECTIVE: To evaluate the results of hepatocellular carcinoma arterial chemoembolization in cirrhotic patients awaiting liver transplantation. MATERIALS AND METHODS: Twenty-three cirrhotic patients with hepatocellular carcinoma awaiting liver transplantation were submitted to multiple sessions of chemoembolization using mitomycin C and lipiodol. A prospective evaluation of the following factors was performed: a) serum levels of alpha-fetoprotein; b) tumor size; c) maintenance of the viability criteria for hepatic transplantation; d) degree of liver dysfunction. RESULTS: The mean serum levels of alpha-fetoprotein were reduced by 43% during the first 13 months. The mean tumor size, as measured by the long axis, after a mean follow-up period of 13.5 months was 3.2 cm, which is considered stable for the period according to the World Health Organization criteria. The mean survival rate was 14 months. CONCLUSION: In this trial, pre-transplantation use of chemoembolization in combination with an adequately chosen therapy showed few complications and contra-indications as well as a considerable anti-tumor efficacy. Despite the fact that the adopted therapy increased survival rates in comparison to historical evolution data in hepatocellular carcinoma, this increase had not the same dimension if the median waiting time for transplantation is taken into consideration. Therefore, other strategies need to be associated to either make survival rate longer or to reduce transplantation waiting time.

Keywords: Hepatocellular carcinoma, Chemoembolization, Lipiodol

OBJECTIVE: To evaluate the response and potential toxicity of fractionated interstitial high-dose rate (HDR) brachytherapy for post-radiation pelvic recurrence in cervical cancer. MATERIALS AND METHODS: From 1998 to 2001, 11 patients aged 41 to 71 years with cervical carcinoma stages II to IV who presented pelvic recurrence after radiation therapy were treated wit interstitial HDR. Nine of these patients (82%) had squamous cell carcinoma and two had adenocarcinoma. Radiation consisted of 20 Gy to 30 Gy delivered in fractions of 4 Gy to 5 Gy over three days. The median follow-up was 22.5 months (2 to 54 months), with periodic physical examinations (three months interval). One patient died without evaluation of the response. RESULTS: Ten patients (91%) presented complete clinical response, three patients (27%) were disease free, two were alive with disease, three (27%) died of cancer and three (27%) were lost in the follow-up after the second recurrence. Urinary tract toxicity grade III was 9% (one patient). CONCLUSION: Interstitial HDR brachytherapy is an alternative approach to selected patients with recurrent cervical carcinoma after radiation therapy. High response rates were achieved with low toxicity taking into account the studied group, time of follow-up and re-irradiation.

Keywords: Recurrent cervical carcinoma, Radiation therapy, High-dose rate brachytherapy, Gynecological cancer

OBJECTIVE: To review the results of adjuvant external beam radiation therapy (EBRT) combined with high-dose rate brachytherapy (HDR-BT) for the treatment of endometrial carcinoma. MATERIALS AND METHODS: We retrospectively evaluated 141 patients treated with EBRT and HDR-BT after surgery between January 1993 and January 2001. EBRT was performed with a median dose of 45 Gy, and HDR-BT was performed with a median dose of 24 Gy, with four weekly insertions of 6 Gy. The median age of the patients was 63 years and the disease stage distribution was: CS I (FIGO), 52.4%; CS II, 13.5%; CS III, 29.8%; CS IV, 4.3%. RESULTS: With a median follow-up of 53.7 months, the disease free survival (DFS) at five years was: CS I, 88.0%; CS II, 70.8%; CS III, 55.1%; CS IV, 50.0% (p = 0.0003). Global survival after five years was: CS I, 79.6%; CS II, 74.0%; CS III, 53.6%; CS IV, 100.0% (p = 0.0062). Factors affecting the DFS were histological grade and serous-papillary histology. Recurrence of the disease was observed in 33 cases, 13 (9.2%) of these occurred in the pelvis, vagina or vaginal vault. EBRT + HDR-BT of the vaginal vault allowed disease control in 90.8% of the cases. CONCLUSION: Radiation therapy is essential for loco-regional control of endometrial cancer and can achieve excellent cure rates in the initial stages. In more advanced stages, therapeutic failure frequently appears as distant metastases suggesting the need for complementary systemic therapy using new treatment modalities, particularly chemotherapy.

Keywords: Carcinoma, Endometrium, Radiation therapy, Brachytherapy

Radioiodine therapy has attained a significant role in the treatment of differentiated thyroid cancer. The literature addressing possible secondary effects of 131I is limited, although there has been increasingly interest in this field. A more comprehensive understanding of the mutagenic effects of radiation on the offspring of women exposed to 131I is mandatory in view of the possibility of occurrence of miscarriages, congenital abnormalities and malignancies in these children. In this review, we found that many reports on safety of this type of treatment in female patients in reproductive age recommend that pregnancy should be avoided for at least one year after therapeutic administration of radioiodine.

Keywords: Radioiodine therapy, Differentiated thyroid carcinoma, Pregnancy

The distribution of fibroglandular tissue in the breast is often symmetrical. Changes in that symmetry may indicate a hidden lesion in the parenchyma. The evaluation of asymmetric densities in the breast is one of the main day-to-day challenges for radiologists, i.e., differentiating normal superimposed structures from true parenchymal lesions. The knowledge of different techniques and resources used to investigate asymmetric densities as well as evaluation protocols are essential to establish the nature of the lesions. Asymmetric densities may be the only sign of breast cancer otherwise clinically and radiologically concealed.

Keywords: Asymmetric density, Mammography, Invasive lobular carcinoma

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

Malignant lesions of the esophagus, other than epidermoids and adenocarcinomas, are remarkably uncommon. The authors report a case of a patient with a spindle cell carcinoma of the esophagus. This is a rare malignant tumor characterized by a large bulky lobulated mass in the middle third of the esophagus that causes relatively little obstruction in spite of its volume. A review of literature is presented.

Keywords: Esophagus, Spindle cell carcinoma, Carcinosarcoma, Pseudosarcoma

Bronchioloalveolar carcinoma is a bronchogenic carcinoma that presents an insidious growth, arises from the walls of the distal air spaces and spreads using the alveolar septa as a stroma, preserving the lung architecture. In this work we analyze the high-resolution computed tomography of 17 patients with bronchioloalveolar carcinoma. Conversely to the data presented in the literature, male preponderance (71%) and a higher frequency of association between multinodular and consolidation patterns (53%) in comparison to single nodular (12%), multinodular (12%) and consolidation (23%) patterns were observed. The most common findings were: consolidation areas (76%), air bronchogram (71%), low attenuation areas (60%), thickening of interlobular septa, ground-glass attenuation and confluent nodules (54% each), and crazy paving pattern (36%). Cavitated nodules, atelectasis, halo sign and "tree in bud" pattern were observed in only one case each.

Keywords: Bronchioloalveolar, Carcinoma, High-resolution computed tomography

We reviewed the case notes and computed tomography scans of 22 patients with squamous cell carcinoma of the vocal cord, in the period between 1992 and 1998. Interobserver concordance for all cases and accuracy and concordance between the methods for the operated patients were evaluated using the kappa test. Concordance was classified as follows: excellent for evaluating tumoral involvement of the thyroid and cricoid cartilages, extralaryngeal extension and lymph node staging; very good for tumoral involvement of vocal cords, posterior commissure and paraglottic space; good for tumoral involvement of the supraglottic and subglottic regions and tumoral staging; regular for tumoral involvement of the anterior commissure and arytenoid cartilage. The combination of clinical and computed tomography evaluation for T staging resulted in an accuracy and concordance with the pathological results of 89.47% and 84.9%, respectively, which were superior to isolated clinical or computed tomography analysis. The accuracy and pathological concordance of computed tomography for N staging was 100%, which was superior to clinical evaluation.

Keywords: Squamous cell carcinoma. Vocal cord. Computed tomography.

PURPOSE: The purpose of this study was to evaluate the relationship between diffuse hypoechoic appearance of the prostate, which is characterized by indistinguishable boundaries between the peripheral zone and the inner gland, and the diagnosis of prostate adenocarcinoma established by transrectal prostate biopsies. MATERIALS AND METHODS: We performed transrectal ultrasonography in 143 male patients with serum prostate specific antigen levels above 4 ng/ml. Randomized biopsies were carried out in all patients. RESULTS: Prostate adenocarcinoma was diagnosed in 36.4% of the patients. Twenty-one (95.4%) out of 22 patients with diffuse hypoechoic appearance of the prostate had positive biopsies for prostate adenocarcinoma. CONCLUSION: Ultrasound diffuse hypoechoic appearance of the prostate is a significant criterion for suspecting adenocarcinoma, since 95.4% of the patients exhibiting this ultrasound findings presented positive biopsies.

Keywords: Ultrasound. Transrectal ultrasound. Prostate carcinoma.

The authors report the case of a patient with a thyroid nodule with benign sonographic and cytopathological features that had presented a decrease of more than 50% in three years and changed its pattern during her pregnancy, being diagnosed as papillary carcinoma. It was concluded that pregnancy can either increase the risk for malignant transformation or accelerate the growth of a malignant thyroid nodule, corroborating pre-existing literature data.

Keywords: Pregnancy; Cancer; Thyroid; Carcinoma; Papillary.

The authors present a case of a neuroendocrine carcinoma in an asymptomatic 75-year-old woman, detected in routine breast screening. The lesion was visible at mammography as a well circumscribed, medium density nodule, with no associated microcalcifications, and at ultrasonography as a hypoechoic nodule, with irregular shape and ill-defined margins. Magnetic resonance imaging revealed findings consistent with malignancy.

Keywords: Carcinoma; Neuroendocrine; Breast; Imaging.

Renal cell carcinoma (RCC) is the seventh most common histological type of cancer in the Western world and has shown a sustained increase in its prevalence. The histological classification of RCCs is of utmost importance, considering the significant prognostic and therapeutic implications of its histological subtypes. Imaging methods play an outstanding role in the diagnosis, staging and follow-up of RCC. Clear cell, papillary and chromophobe are the most common histological subtypes of RCC, and their preoperative radiological characterization, either followed or not by confirmatory percutaneous biopsy, may be particularly useful in cases of poor surgical condition, metastatic disease, central mass in a solitary kidney, and in patients eligible for molecular targeted therapy. New strategies recently developed for treating renal cancer, such as cryo and radiofrequency ablation, molecularly targeted therapy and active surveillance also require appropriate preoperative characterization of renal masses. Less common histological types, although sharing nonspecific imaging features, may be suspected on the basis of clinical and epidemiological data. The present study is aimed at reviewing the main clinical and imaging findings of histological RCC subtypes.

Keywords: Renal cell carcinoma; Kidney cancer; Computed tomography; Magnetic resonance imaging.