[Distribution and frequency of gastric cancer at the para-cardiac region and fornix]

To clarify the distribution and frequency of gastric cancer in the upper third of the stomach, especially in the para-cardiac region and fornix, we reviewed 634 lesions of all gastric cancers in any location in the University Hospital of Tsukuba University from April 1985 to March 1992. The para-cardiac region was defined as a circular area of 6 cm in diameter around the cardia. We found 56 lesions (8.8%) in the para-cardiac region, almost all of which were concentrated in the distal half of the para-cardiac region, and only three of which (0.47%) were in the fornix. Cancer in the upper third of the stomach tended to occur predominantly in aged male patients, and histologically most of them were classified as having differentiated adenocarcinoma. Since the percentage of advanced cancer at the para-cardiac region was much higher than at any other location, we should be careful to obtain double-contrast images of sufficient quality during the upper gastrointestinal examinations and not to overlook subtle changes in this region during the interpretation of films.

Hepatic peribiliary cysts: multiple tiny cysts within the larger portal tract, hepatic hilum, or both

PURPOSE

To describe characteristic imaging features of hepatic peribiliary cysts.

MATERIALS AND METHODS

Four patients with hepatic cysts in which the radiologic (n = 3) or histologic (n = 1) findings were consistent with peribiliary cysts of the liver (multiple small cysts seen exclusively in the larger portal tract, hepatic hilum, or both at gross examination and dilatations of extramural peribiliary gland at histologic examination) underwent computed tomography (CT) and ultrasound (US). In three patients, CT was performed after drip infusion of cholangiographic contrast material.

RESULTS

Contrast material-enhanced CT clearly depicted many tiny cysts along the larger portal veins up to the third- or fourth-order branch (n = 3). US depicted multiple cysts in the echogenic portal tract definitely (n = 2) or equivocally (n = 2). On cholangiographic contrast-enhanced CT scans, cystic areas were located adjacent to or surrounding the bile ducts, and the possibility of biliary dilatation, communication, or both was disproved.

CONCLUSION

Hepatic peribiliary cysts can be diagnosed with US and enhanced CT, especially with CT performed after administration of cholangiographic contrast material.

Metastatic tumors in irregular fatty liver mimicking focal sparing

Two cases of hepatic metastatic tumor occurring in irregular fatty liver are reported. These metastatic tumors appeared as irregularly shaped hyperdense areas and were difficult to distinguish from focally spared areas of irregular fatty liver. Even if areas of focal sparing are irregular in shape, hepatic tumors should be carefully ruled out in patients at high risk for liver tumors.

[The evaluation of lung cancers hidden by the mediastinal and hilar shadows on the plain chest film]

We retrospectively evaluated the plain chest frontal radiographs in four cases in which the lung cancers were quite difficult to observe prospectively on plain chest frontal radiographs in spite of the relatively large size of tumors (over 3 cm in diameter). Three of four cases were central-type lung cancers, two squamous cell carcinomas and one adenosquamous cell carcinoma. Since there was no associated atelectasis or obstructive pneumonia in these cases, wall thickening and indistinctness of the lumen of the central bronchi were the significant findings for diagnosis. One case proven to be adenocarcinoma was located in the periphery of S6. A focally increased radiopacity behind the descending pulmonary artery was the only finding to pointed out. Since tumors were not demonstrated directly in the aerated lungs, the condition of the central bronchi as well as the degree radiopacity of the pulmonary artery should be carefully interpreted.

Long-term survivors after salvage surgery combined with radiotherapy for recurrence of stage IV main hepatic duct cancer--report of two cases

Main hepatic duct cancer is notorious for its poor prognosis and frequent locoregional failure of therapy even after curative resection. In this paper, two cases of recurrent carcinoma of the stage IVA main hepatic duct are presented. One patient had local failure 13 years after curative resection of the tumor and the other had regional failure 18 months after combination treatment with non-curative resection and intra-operative radiation therapy. Recurrent tumors were successfully treated with combined resection and postoperative radiation therapy or with combined intra-operative radiation therapy and postoperative radiation therapy. The patients are well 16.9 and 6.3 years, respectively, after primary tumor resection. We briefly review a number of other reports of salvage treatment in patients with recurrent carcinoma of the main hepatic ducts and discuss the results with particular reference to the advantage of salvage therapy for the main hepatic duct cancer.

Angiographic findings of Meckel's diverticulum: the characteristic appearance of the vitelline artery

Angiographic findings of the vitelline artery in five patients with surgically proven Meckel's diverticulum were reviewed retrospectively. Superselective vitelline arteriography was performed in two patients and superior mesenteric arteriography in three. Arteriography showed the elongated artery without branching originating from the distal ileal artery and a group of tortuous vessels at the distal portion of this artery in all patients. A dense capillary staining of the vitelline artery was exclusively shown in patients with ectopic gastric mucosa. In one patient, injection of methylene blue intraoperatively through a previously placed angiographic catheter into the vitelline artery stained only the vitelline artery and Meckel's diverticulum in blue but neither the mesentery nor the ileum. Demonstration of a nonbranching artery from the ileal artery and a group of dilated tortuous vessels at the distal portion of this artery should suggest the possibility of Meckel's diverticulum and can be confirmed by selective injection of the artery. It should be emphasized that angiography can detect Meckel's diverticulum even in the absence of acute bleeding.

[CT of pulmonary dirofilariasis--differential diagnosis from lung cancer]

We present here four cases of pulmonary dirofilariasis in which histological examination of the surgical specimen showed occlusion of the peripheral pulmonary artery by filariae and formation of a necrotic mass surrounded by reactive inflammation and hemorrhage. Radiological examination showed a solitary pulmonary nodule in three cases and a wedge-shaped consolidation in one case. Although pulmonary nodules in dirofilariasis closely mimic bronchogenic carcinoma on radiographs , it is possible to distinguish them from bronchogenic carcinoma on the basis of the following findings: (1) coexistence of subtle satellite lesions, (2) absence of pleural involvement, (3) fine marginal speculations, and (4) lack of concentric marginal speculations (eccentric speculation). In each case of dirofilariasis, CT showed the peripheral pulmonary artery entering the mass. This finding differentiates this disease from metastatic lung tumor, because in tumor metastasis via the pulmonary arteries, visible vessels are not usually involved.

[Computed tomographic evaluation of thickness of perirectal fascia in rectal cancer treated by preoperative radiotherapy--diagnostic value for prediction of local recurrence]

Perirectal fascia was examined by computed tomography before and after preoperative radiotherapy in thirty-six patients with rectal cancer. CT measurement showed that perirectal fascia tend to increase in thickness during preoperative radiotherapy in proportion to tumor extension into perirectal fat tissue. The fascial thickening more than 7 mm after preoperative radiotherapy was suggestive of local recurrence to develop. Preoperative or intraoperative boost irradiation would be recommended for such high-risk patients.

[Gastric cancer and obstructive uropathy]

In recent 5 years, we have experienced 24 cases of advanced gastric cancer associated with obstructive uropathy. Included were 19 cases of undifferentiated, 3 cases of differentiated and 2 cases of unknown histological type. Obstructive uropathy is diagnosed based on the typical radiological findings such as dilatation and delayed demonstration of the upper collecting systems. Pathologically, undifferentiated type of gastric cancer had tendency to spread infiltrating along the vessels, nerves and the lymphatics without alteration of the ordinary anatomical structures. In such cases, mucosal surface of the urinary tract tended to be spared in spite of extensive tumor invasion. It was proven that several radiological findings were characteristic of urinary tract involvement secondary to gastric cancer. Either thread-like ureteral stricture by IVU or ring-like appearance of the ureter by CT is one of those typical findings. Renal sinus involvement may occur continuously to diffuse retroperitoneal invasion and it appears as a thickened wall of renal pelvis or soft tissue mass directly extending into the fatty tissue of renal sinus by CT. In such cases IVU has less diagnostic ability because of the lack of mucosal destruction. If the urinary bladder is involved, it typically shows chestnut-bur appearance by IVU and diffuse wall thickening by CT. In cases of advanced gastric cancer, particularly in cases of histologically undifferentiated type, CT and IVU images should be carefully interpreted in consideration of the infiltrative art of tumor extension.

[Pulmonary infarction associated with bronchogenic carcinoma]

Pulmonary infarction may be associated with bronchogenic carcinoma. Radiopathological correlation was performed in four patients. There were two cases of squamous cell carcinoma, one case of adenocarcinoma and one case of large cell carcinoma. Infarcts in patients with squamous cell carcinoma were obscured on plain radiographs by a large primary tumor or atelectasis of the affected lobe. Infarcts in adenocarcinoma and large cell carcinoma were clearly demonstrated on plain radiographs; 1 to 2 cm in size, round or polygonal in shape, blurred in margin, and located at the periphery of the same lobe as the primary tumor. Rapid appearance of infarcts was helpful in distinguishing from intrapulmonary metastasis. Invasion of the pulmonary artery, pulmonary vein and bronchial wall in hilar region was thought to be responsible for pulmonary infarction. Pulmonary infarct should be considered in patients with centrally invasive bronchogenic carcinoma, when a small ill-defined opacity appears at the periphery of the involved lobe over a short period.

[Clinical signification of localization of S protein and late components in the skin from lupus patients]

We studied frozen tissue of lesional skin and normal-appearing skin from SLE patients and DLE patients by immunofluorescence. S-protein and late components (C5, C7, C9) were localized at the dermal-epidermal junction of the lesional skin from SLE and DLE patients. All specimens of normal-appearing skin from patients with SLE were free of deposits of S-protein and late components. These results suggest that late components may play a role in the development of skin lesions of SLE and DLE.

[Extramedullary haematopoiesis as a cause of a paravertebral mass in the thorax (author's transl)]

The radiological due to extensive extramedullary haematopoiesis taking place in the posterior mediastinum in two patients are described, and the literature is reviewed. Characteristic features are a polycyclic or spindle-shaped configuration of the mass, with bilateral paravertebral localisation in the caudal and middle third of the thorax. There is absence of inflammatory or neoplastic changes in the neighbouring skeleton, but in thalassaemia there may be changes in the paravertebral portion of the ribs. Computer tomographically, the combination of a solid paravertebral tumour, with adjacent rib changes, is characteristic of thalassaemia with extramedullary haematopoiesis. In the absence of other skeletal changes, computed tomography is valuable for differential diagnosis. Lymphomas occur considerably more often and may appear identical but, because of the well know fat content of myolipoma, the scan shows contrast values between -15 and + 40 HU. Because of their high vascularity, there is a marked increase in density following intravenous contrast medium.

[A special type of hyperplastic polyps of the stomach (author's transl)]

Five patients with hyperplastic polyps of the stomach were found in the course of 573 double contrast examinations over a period of six and a half months. The radiological findings were similar in all cases, consisting of multiple small round mucosal elevation with sharp margins, situated in the body of the stomach. They can probably extend into the fundus and the pylorus. Histological examination has indicated that these polyps are the result of an inflammatory process.