[Gastric stromal tumors. Findings with computerized tomography]. / Tumori stromali gastrici. Aspetti con Tomografia Computerizzata.

PURPOSE: Gastric stromal tumors are an ill-defined group of lesions arising from muscle wall cells and characterized by extremely variable biological patterns. Thanks to modern immunohistochemical and ultrastructural techniques, four main classes of these lesions have been identified, namely: 1) tumors with differentiation toward smooth muscle cells; 2) tumors with differentiation toward neural elements; 3) tumors with dual differentiation toward both cell types; 4) tumors lacking differentiation toward either cell type. We investigated the yield of CT in diagnosing and characterizing gastric stromal tumors. MATERIAL AND METHODS: We retrospectively reviewed the CT findings of 38 patients (15 men and 23 women; mean age 51 years) with pathologically proven gastric stromal tumors, namely 31 of myoid origin, 4 of neural origin, 2 with both muscle and neural differentiation, 1 lacking differentiation with either cell type. Morphological (size, margins, growth pattern, enlarged lymph nodes, metastases) and structural (density, calcifications, necrosis, cystic changes, enhancement patterns) parameters were evaluated and compared with histopathologic diagnosis. RESULTS: The myoid tumors involved gastric fundus in 9/13 and 5/7 benign lesions and lesions with variable biological patterns, respectively, while the malignant tumors exhibited diffuse involvement in 7/11 of cases. Eleven of 13 benign lesions had regular shape and a diameter +/- 5 cm, while 5/7 intermediate tumors and 7/11 malignant ones were 6-10 cm and over 10 cm (1/7 and 3/11, respectively). Tumor growth was intramural (6/13) or mixed (5/13) in the benign lesions, mainly exophytic in the malignant ones, and finally variable (2/7 intramural, 3/7 exophytic and 2/7 mixed) in the tumors with intermediate patterns. Calcifications were identified only in 3 benign lesions. Structure was homogeneous in 11/13 of the benign lesions with regular contrast enhancement (10/12), heterogeneous due to necrotic areas in nearly all (10/11) or most (5/7) malignant and intermediate forms, respectively. Enlarged lymph nodes (4/11) or synchronous metastases (7/11) were found in the malignant lesions. Our two schwannomas had a pseudocystic structure with regular peripheral contrast enhancement; the neurofibroma was characterized by multiple, markedly hypodense and hypovascular lesions. Both the malignant neurogen form and the two tumors with dual differentiation showed a diffuse, aspecific and infiltrating pattern. The lesion without differentiation had a "benign" shape and structure even though it developed metastases two years after radical surgery. CONCLUSIONS: Despite the lack of specificity of CT patterns of gastric stromal tumors, these parameters are useful in differentiating benign from overtly malignant forms. The definition "gastric stromal tumor with benign, variable, or malignant macroscopic appearance" should be used in the radiologic report.

[Endometriosis of the ileum and colon complicated by intestinal obstruction. Report of two cases]. / Endometriosi dell'ileo e del colon complicata da occlusione intestinale. Due casi clinici.

The authors report two cases of intestinal occlusion, one ileal and the other colic, caused by endometriosis. Both patients underwent surgery. Following a review of data in the literature regarding the frequency, pathogenesis, diagnosis and management, the authors conclude that pre- and intraoperative diagnosis is often impossible in these cases and must be postponed to histological analysis. Full remission was achieved after surgery.

Percutaneous radiofrequency thermal ablation combined with transcatheter arterial embolization in the treatment of large hepatocellular carcinoma.

PURPOSE: To evaluate whether the combination of hepatic segmental transcatheter arterial embolization (TAE) with percutaneous radiofrequency (RF) ablation can increase the volume of coagulation necrosis to treat patients with large hepatocellular carcinoma (HCC). METHOD: Fourteen patients with cirrhosis and HCC whose greatest diameter ranged from 3.8 to 6.8 cm (mean, 5.2 cm) underwent segmental TAE followed within 3 days by RF interstitial thermal ablation with an expandable needle electrode inserted into the tumour under sonographic guidance, after local anesthesia. We made one or more needle electrode insertions depending on tumor shape. Posttreatment necrosis was evaluated by ultrasonography, dynamic computed tomography (CT) and alpha-fetoprotein dosage in all cases, repeated every three to four months. RESULTS: Tumor ablation was obtained in one session in 11 (78%) patients (with one needle electrode insertion in 8 patients), in two sessions in 1, in three sessions in 2. In a mean follow-up of 13.2 months (range 6-23) two patients died from unrelated causes; one patient showed multinodular HCC 6 months after the treatment; 4 patients developed new lesions, treated by a new course of RF ablation (3 cases) or by surgery (1 case); therefore 11/12 patients still in follow-up were disease-free. No fatal complications were observed. One month after the treatment, fluid collection at the site of the ablated tumor was observed in one patient which was percutaneously drained. CONCLUSIONS: Percutaneous RF thermal ablation performed after TAE effectively treated HCCs larger than tumors suitable for segmental TAE or RF application alone; the result was achieved in two thirds of the cases in a single session with only one needle electrode insertion.

Relationship between the shape and size of radiofrequency induced thermal lesions and hepatic vascularization.

AIMS AND BACKGROUND: The aim of this study was to evaluate the relationship between hepatic vascularisation and the final size and shape of radiofrequency (RF) induced thermal lesions. METHODS: Series of four RF thermal lesions were created in explanted calf livers and in pig livers maintaining the following experimental conditions throughout the procedure: normal hepatic perfusion, occlusion of the hepatic artery, occlusion of the portal vein, occlusion of both hepatic artery and portal vein (Pringle maneuver) and subtotal occlusion of the hepatic veins. A 14G expandable needle electrode was used to make the thermal lesions. Each lesion was created applying predetermined temperatures ranging between 95 and 115 degrees C and an exposure time of 20 minutes. RESULTS: Occlusion of the hepatic artery during the RF procedure resulted in moderate and not significant increases in thermal lesion diameter compared with those obtained in normally perfused liver (3.0 +/- 0.4 cm vs 3.0 +/- 0.2 cm), while occlusion of the portal vein resulted in larger lesion diameters (3.5 +/- 0.3 cm). In both these cases the diameters of the thermal lesions were smaller than those obtained in explanted calf liver (4.0 +/- 0.3 cm) and their shape showed peripheral irregularities. Thermal lesions larger than those seen in normally perfused liver and equaling those observed in explanted calf liver were created both during the Pringle maneuver (4.0 +/- 0.2 cm) and after subtotal occlusion of the hepatic veins (4.0 +/- 0.3 cm). In both these cases the thermal lesions were regular in shape. CONCLUSIONS: Occlusion of the blood flow during the RF procedure avoids heat loss by convection, resulting in the creation of larger thermal lesions than those obtained in normally vascularized liver using the same electrode, temperatures and exposure time. This technique could therefore be employed in humans to destroy large hepatic tumor nodules.

[Jejunal diverticulosis. Presentation of a clinical case]. / Diverticolosi digiunale. Presentazione di un caso clinico.

Jejunal diverticulosis is a rare and often asymptomatic disease, generally presenting as an occasional finding during laparotomy for other diseases. There are no established criteria for the treatment of such diverticula. Due to the possible onset of acute complications, surgical management must be considered. Personal experience on a case of jejunal diverticulosis in a woman who presented with acute complications of surgical peritoneal adhesions is described. Through examinations of small intestine discovered many diverticula, mainly in the mesenteric side; two diverticula were particularly large. Even though there appeared to be no symptoms due to the diverticula, major diverticula were considered at risk for acute complications. Because their reduction was not easily achievable, they were resected and enterotomies were stitched. Postoperative course was uneventful and after 2 years the patient is alive and well. Features of this rare entity are analyzed with regard to data reported in the literature, with special reference to some pathogenetic theories.

Percutaneous treatment of small hepatic tumors by an expandable RF needle electrode.

OBJECTIVE: The aim of this study was to evaluate the usefulness of expandable RF needle electrodes in the treatment of hepatic cancer. SUBJECTS AND METHODS: Thirty-seven patients, 23 of whom had 26 hepatocellular carcinoma nodules and 14 of whom had 19 hepatic metastatic nodules, underwent treatment by RF interstitial thermal ablation with expandable needle electrodes. Forty-five tumor nodules were treated in 64 RF interstitial thermal ablation sessions with 83 needle electrode insertions. The mean diameter of the tumor nodules was 2.5 cm (range, 1.1-3.5 cm). Immediate posttreatment tumor necrosis was evaluated by dynamic CT in all cases. Two patients with hepatocellular carcinoma and three patients with metastases underwent surgical resection 20-60 days after RF treatment. The remaining 32 patients were followed up clinically. RESULTS: The mean number of RF interstitial thermal ablation sessions to complete tumor nodule treatment was 1.4. Mean number of needle electrode insertions was 1.8. No complications were observed. Posttreatment dynamic CT showed a completely nonenhancing area in the site of the treated tumor in 44 of 45 cases. The remaining patient with metastatic disease had persistent enhancing tissue. Histology showed complete necrosis in four treated tumor nodules and residual viable cancer in one. Twenty-one patients with hepatocellular carcinoma were followed up for 6-19 months (mean, 10 months). Of these patients, six showed recurrences and 15 remained apparently disease-free. Two patients died, one from advanced cancer and one from other causes. Eleven patients with hepatic metastases were followed up for 7-20 months (mean, 12 months). Of these patients, nine showed recurrent disease and only two remained apparently disease-free. Two patients died from disseminated disease. CONCLUSION: RF interstitial thermal ablation of hepatic tumor by expandable needle electrodes is a safe and effective technique. Local ablation of tumors not exceeding 3.5 cm in diameter is achieved in a short time without complications.

Natural history, clinicopathologic classification and prognosis of gastric ECL cell tumors.

A series of 50 gastric endocrine tumors classified according to Rindi et al. [1] comprised 12 small cell neuroendocrine carcinomas (NEC) and 38 ECL cell carcinoids, of which 22 associated with type A chronic atrophic gastritis (A-CAG), eight with hypertrophic gastropathy due to combined Multiple Endocrine Neoplasia and Zollinger/Ellison syndrome (MEN/ZES), and eight sporadic. Variables found to predict tumor malignancy were: size > 2 cm, > 2 mitoses and > 130 Ki67 positive cells/10 high power fields (HPF), grade 2 or 3 histology, angioinvasion, p53 protein nuclear accumulation, and the presence of a single tumor. None of these factors increased significantly the predicting ability of tumor classification itself, although grade 2 + 3 shows 100 percent negative predictive value and Ki67 and angioinvasion 100 percent positive predictive value. When the mostly non-malignant A-CAG and MEN-ZES tumors were analysed against the mostly malignant sporadic and NEC tumors, a positive predictive value of 90 percent and a negative predictive value of 93 percent was obtained. Investigation of a larger tumor series is under way with the aim to develop an optimal model for prognostic evaluation of gastric endocrine tumors.

Primary liver leiomyosarcoma: CT appearance.

Primary hepatic leiomyosarcomas are exceedingly rare tumors. To the best of our knowledge, only 17 cases have been reported in literature. We report the computed tomographic findings of two cases of primary location in the liver. We also discuss the differential diagnosis of such lesions.

Apocrine carcinoma of the skin. A clinicopathologic, immunocytochemical, and ultrastructural study.

BACKGROUND: Apocrine carcinomas of the skin are rare and incompletely studied neoplasms. METHODS: An immunohistochemical and ultrastructural study is reported of specimens from six patients with apocrine skin carcinoma in various body sites. Three tumors were in the axilla; one, the eyelid; one, the ear; and one, the scalp. There were three local recurrences and three regional lymph node metastases, but no patient died of cancer (follow-up, 2-10 years). RESULTS: The most reliable histopathologic criteria for identifying apocrine skin carcinoma appear to be decapitation secretion, periodic acid-Schiff-positive diastase-resistant material in the cells or lumen, and immunoreactivity with gross cystic disease fluid protein 15. All specimens expressed common epithelial antigens (cytokeratins, carcinoembryonic antigen, and epithelial membrane antigen) and histiocytic-secretive antigens (Leu-M1, lysozyme, LN5, alpha-1-antitrypsin, and alpha-1-antichymotrypsin). S-100 protein was found in the three nonaxillary tumors. Ultrastructurally, the primary tumors, and especially the secondary lesions, were dedifferentiated compared with normal apocrine glands. CONCLUSIONS: Apocrine differentiation in skin tumors does not indicate an exclusive origin from the apocrine sweat glands; these neoplasms usually have an indolent clinical course.

Angiosarcoma of the adrenal gland. Case report.

The vascular tumours of the adrenal gland are rare, both the benign and the malignant ones. Twenty two cases from the literature are reviewed in a paper by Kareti et al., 1988, among which only one own case of angiosarcoma the authors deem to be the first to be reported. A second case of angiosarcoma of the left adrenal gland, in a 67 y. old man, is herein reported. Notwithstanding a through surgical removal, a quick fatal progression of the disease ensued. Perhaps, considering the high malignancy of these rare tumours, an adjuvant form of treatment seems to be advisable.

Multidirectional carcinoma of the thymus with neuroendocrine and sarcomatoid components and carcinoid syndrome.

We report a case of metastatic thymic neoplasm occurring in a 62-year-old Caucasian man. The tumor was polymorphic, with intimately admixed carcinoid, sarcomatous and undifferentiated components. Sarcomatous cells were spindle-shaped and immunoreactive for vimentin, actin and desmin. Carcinoid cells reacted for cytokeratin as well as with a panel of general neuroendocrine markers, including chromogranins A and B, synaptophysin, protein gene product (PGP) 9.5, neuron specific enolase (NSE), Leu 7 and Grimelius' silver. The endocrine nature of the latter cells was confirmed by ultrastructural evidence of abundant electron-dense granules 100 to 300 nm in size. Among the various hormones investigated immunohistochemically only the alpha chain of human chorionic gonadotropin (alpha-hCG) was detected in tumor cells. The neoplasm recurred after surgical resection and caused a typical carcinoid syndrome with skin flushing and increased urinary 5-hydroxyindolacetic acid (5-HIAA). The diagnosis of multidirectional thymic carcinoma with two lines of differentiation, of carcinoid and sarcomatoid type, was made.

Turcot's syndrome with intestinal lymphoma in a child: an unusual case of triple tumor.

Turcot's syndrome, the association of brain tumor (usually glioblastoma, medullo-blastoma, or astrocytoma) and colonic polyps, is a very rare condition of which about 20 cases have been reported. It has been described only once previously with cancer in a third organ system. In this paper, we report a child affected with colonic polyposis and astrocytoma (i.e., Turcot's syndrome) associated with intestinal non-Hodgkin's lymphoma.

Dextran deposits in tissues of patients undergoing haemodialysis.

Recently the possible storage of dextran-related material in patients undergoing regular haemodialysis has been suggested. We examined biopsy and autopsy specimens of 32 patients treated with regular haemodialysis for 61 +/- 34 months. All patients received dextran-40 as a plasma expander because of hypotension during haemodialysis. The same study was carried out in a control group of 11 haemodialysed patients who were given other plasma expanders. In the 11 patients who received larger doses of dextran-40 (0.38 g/kg body weight per week) we found particles in the cytoplasm of macrophages in various organs, which proved PAS positive and diastase resistant on light microscopy, and birefringent on polarisation. Electron microscopy revealed a fibrillar structure, but ionic analysis by electronic sampler on scanning electron microscopy excluded the presence of silicon. No intracellular inclusions were observed in the control group, nor in the patients given dextran-40 in doses lower than 0.08 g/kg body weight per week. As we also found a linear relationship between the number of particles and the dextran-40 doses given, we hypothesise that the material demonstrated in the macrophages is a structurally modified dextran.