Development of a rat lung cancer model.

A rat lung cancer model based on intrabronchial instillation of a tumor cell suspension has been developed for use in therapy and toxicity testing. Two tumors were used in this study, a sarcoma and an adenocarcinoma, both of which were of spontaneous origin in the strain of rats used. The inoculated tumor cells implant on the bronchiolar mucosa, forming a detectable single "primary" tumor resembling the spontaneous lung cancers arising in humans. The tumor growth is detectable by use of diagnostic radiographs, weight loss and other "clinical" signs. The tumors appear on chest radiographs 3 to 5 weeks after inoculation, and the implant rate is proportional to the number of tumor cells inoculated. Untreated animals have a median survival (after radiographic detection of the tumor) of 8 days, and die of local complications of tumor growth. When a slow growing transplantable tumor line of lung origin is developed, this model will be used to evaluate radiotherapy and chemotherapy schedules.

Non-Hodgkin's lymphoma presenting as malignant pericardial effusion and cardiac tamponade.

A case of malignant lymphoma, Rappaport histiocytic type, in which the initial clinical presentation was malignant pericardial effusion with cardiac tamponade is presented. The pathogenesis of malignant pericardial effusion is discussed, and the value of cytology in the diagnosis of malignant pericardial effusion is emphasized.

Combined robotic and nonrobotic telepathology as an integral service component of a geographically dispersed laboratory network.

To achieve real-time connectivity between its 8 hopital-based laboratories, Veterans Integrated Service Network (VISN) 12, headquartered in Chicago, IL, has implemented a hybrid dynamic store-and-forward (HDSF) telepathology network that extends across portions of 3 states. The majority of diagnostic telepathology functions are provided to the 3 hospitals (Iron Mountain, MI; Tomah, WI; and North Chicago, IL), which lack on-site pathologists and are serviced by the 4 pathologists located in Milwaukee, WI. In surgical pathology, routine primary diagnosis, frozen section diagnosis, and clinical consultation are provided with telepathology. In addition, autopsy and specialty clinical conferences are frequently performed by using telepathology. Telepathology has been applied to a variety of areas within clinical pathology as well, including protein electrophoresis, immunoelectrophoresis, peripheral blood smears, body fluids, microbiology, and distance learning. Implementation of telepathology has allowed VISN 12 to reach the goal of providing a single standard of accurate and timely pathology service, even at small sites that lack an on-site pathologist.

Dynamic-robotic telepathology: Department of Veterans Affairs feasibility study.

In this retrospective study, we assess the accuracy, confidence levels, and viewing times of two generalist pathologists using both dynamic-robotic telepathology and conventional light microscopy (LM) to render diagnoses on a test set of 100 consecutive routine surgical pathology cases. The objective is to determine whether telepathology will allow a pathology group practice at a diagnostic hub to provide routine diagnostic services to a remote hospital without an on-site pathologist. For TP, glass slides were placed on the motorized stage of the robotic microscope of a telepathology system by a senior laboratory technologist in Iron Mountain, MI. Real-time control of the motorized microscope was then transferred to a pathologist in Milwaukee, WI, who viewed images of the glass slides on a video monitor. The telepathologists deferred rendering a diagnosis in 1.5% of cases. Clinically important concordance between the individual diagnoses rendered by telepathology and the "truth" diagnoses established by rereview of glass slides was 98.5%. In the telepathology mode, there were five incorrect diagnoses out of a total of 197 diagnoses. In four cases in which the telepathology diagnosis was incorrect, the pathologist's diagnosis by LM was identical to that rendered by telepathology. These represent errors of interpretation and cannot be ascribed to telepathology. The certainty of the pathologists with respect to their diagnoses was evaluated over time. Results for the first 50 cases served as baseline data. For the second 50 cases, confidence in rendering a diagnosis in the telepathology mode was essentially identical to that of making a diagnosis in the LM viewing mode. Viewing times in the telepathology mode also improved with more experience using the telepathology system. These results support the concept that an off-site pathologist using dynamic-robotic telepathology can substitute for an on-site pathologist as a service provider.

Glomus tumor of the stomach. Histologic and ultrastructural features.

A glomus tumor of the stomach was found in a 79-year-old white man who had episodes of upper gastrointestinal bleeding. Clinically, this uncommon gastric tumor mimics most of the benign and malignant lesions of the stomach. The most important aspect of this tumor, therefore, is its histologic identification and differentiation from the more common gastric lesions, most especially malignant tumors. This is of paramount importance because the glomus tumor is essentially benign and does not warrant a radical surgical procedure. The histologic and ultrastructural features of this particular gastric neoplasm are presented and discussed.

Richter's syndrome presenting as primary central nervous system lymphoma. Transformation of an identical clone.

The development of a central nervous system (CNS) large cell lymphoma in a patient simultaneously diagnosed with chronic lymphocytic leukemia (CLL) is reported. Although differences in phenotypic expression were demonstrated in study of the peripheral blood and CNS disease, identical immunoglobulin gene rearrangements were identified, providing evidence for evolution of two morphologically distinct neoplasms from the same clone. Beyond histologic transformation, acquisition of an aneuploid cell population in the CNS tumor was demonstrated by analysis of DNA content. Isolated parenchymal involvement of the CNS by large cell transformation of CLL has not been previously described; its relationship to CNS lymphoma and Richter's syndrome are reviewed.

Splenic phagocytic function after partial splenectomy and splenic autotransplantation.

We investigated splenic reticuloendothelial activity after splenic preservation procedures to determine their effect upon the phagocytic function of the spleen. We performed the following procedures in Sprague-Dawley rats: sham laparotomy, total splenectomy, hemisplenectomy, subtotal splenectomy, or total splenectomy with intraperitoneal splenic autotransplantation. At nine weeks after operation, phagocytic function of the spleen was determined by measuring radiocolloid uptake. Mean (+/- SEM) splenic phagocytic indices for sham laparotomy (41.2 +/- 2.9), hemisplenectomy (44 +/- 2.9), and subtotal splenectomy (43.2 +/- 5.2) were similar; however, the phagocytic index was reduced markedly after autotransplantation (15.8 +/- 2.2). These data demonstrate that the phagocytic function of the spleen after hemisplenectomy and subtotal splenectomy correlates highly with the weight of the splenic remnant; however, phagocytic function after autotransplantation remains reduced even after accounting for differences in splenic weight.

Metastatic tumors involving testis.

Two cases of metastatic tumors involving the testis are reported: one from an adenocarcinoma of the prostate and the other from an adenocarcinoma of the colon. The first was found incidentally in the orchiectomy specimen done for prostatic cancer while the other was noted clinically as a part of a widely disseminated disease. Although there are numerous pathways through which tumors may metastasize to the testis, the occurrence of testicular metastasis is extremely rare. The reason for this rarity remains unknown.

Primary renal carcinoid tumor.

A case of primary renal carcinoid tumor in a sixty-seven-year-old man is presented. Radical nephrectomy removed the primary disease, but hepatic metastases developed and the patient subsequently died. Review of the literature disclosed 8 other cases of primary renal carcinoid. Three of these had metastatic spread.

The prognostic significance of histologic subtyping in small cell carcinoma of the lung.

Previously untreated patients with small cell carcinoma of the lung (SCCL), who were treated at the Medical College of Wisconsin with combined chemotherapy and radiation therapy, were retrospectively subtyped according to the 1981 World Health Organization Lung Cancer Classification. Of 54 evaluated patients, 27 (50%) had "oat cell" subtype, 22 (41%) "intermediate cell" variety, and five (9%) were classified as "combined" type. There was no significant difference in response to therapy or median survival between the subtypes. In addition to the absence of prognostic significance among the subtypes, there were many technical factors affecting accuracy of subtyping, including tissue-crushing artifacts, size of biopsy materials, fixation of tissue samples, and variation of subtypes within the same biopsy. We conclude that subtyping of SCCL should not be construed as a prognostic tool or guideline to therapy. However, the recognition that SCCL may manifest in a variety of histologic patterns, some of which may be misinterpreted as a histology other than SCCL, is probably more important for choice of therapy and prognosis than the individual subtypes.

Hemangioma in a lymph node.

Hemangiomas occurring in lymph nodes are extremely rare and, to our knowledge, have been documented in the literature only once previously. We report an additional case that was found incidentally in a patient who had undergone a right hemicolectomy and small-bowel resection for widespread angiodysplasia. In addition, the patient also had a third type of vascular lesion, namely, a hemangiopericytoma of the oral mucosa. We also reviewed the literature regarding vasoformative lesions occurring in lymph nodes.

Papillary fibroelastoma of the heart. Report of six cases.

Papillary fibroelastoma is a rare cardiac lesion, mostly encountered as an incidental finding at the time of autopsy but occasionally seen during life. Although this condition generally is asymptomatic, a few cases had been associated with clinical problems, such as embolic phenomena, angina pectoris, outflow tract obstruction, and sudden death. We studied six examples of this lesion, five occurring on the cardiac valves and one on the left ventricular septum. In one, the lesion was detected by echocardiography, which represents to our knowledge only the third published case in which the lesion was visualized by this diagnostic procedure and only the fourth in which the lesion was seen during life. We believe that echocardiography is sensitive in the detection of this often small, intracardiac lesion, useful in evaluating whether a case, by virtue of its size or location, carries a significant risk of causing clinical problems and therefore requires treatment.

Argyrophilic, 'carcinoid-like' prostatic carcinoma. An immunocytochemical study.

Four cases of argyrophilic or carcinoid-like prostatic carcinoma were studied immunocytochemically, using immunoperoxidase stains for prostatic-specific antigen, neuron-specific enolase, hydroxytryptamine (serotonin), somatostatin, and adrenocorticotropic hormone. All four showed strong positive reaction to prostatic-specific antigen and uniformly negative results with neuron-specific enolase, hydroxytryptamine, somatostatin, and adrenocorticotropic hormone. These findings lend further support to the concept that this particular prostatic tumor is truly a carcinoma that somehow manifests a carcinoid-like histomorphology, but does not possess evidence of true neuroendocrine or carcinoidal nature.

Injuries to the bronchi and lungs caused by laser-ignited endotracheal tube fires.

A CO2 laser attached to an operating room microscope was used to produce extraluminal and intraluminal ignition of various endotracheal tubes in dogs. Extraluminal ignition was produced in Silastic and red rubber endotracheal tubes. The red rubber tube ignited before the tube lumen was penetrated. The Silastic tube failed to ignite while the cuff was inflated. When the cuff was deflated, ignition occurred before the lumen was penetrated. No lung or bronchial injuries were detected in the red rubber or Silastic endotracheal tube extraluminal fires. Intraluminal fires were produced in Silastic, red rubber, and polyvinylchloride (PVC) endotracheal tubes. Microscopic examination of the bronchi and lungs revealed severe injuries in dogs intubated with the PVC and red rubber endotracheal tubes. No injuries to the bronchi and lungs were detected in the Silastic tube group, although the potentially toxic effects of silica ash require further investigation.

Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch.

A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis.

Argyrophilic prostatic carcinoma. Case report with literature review on prostatic carcinoid and "carcinoid-like" prostatic carcinoma.

An unusual prostatic neoplasm characterized by a carcinoid-like light microscopic pattern together with argyrophilia of tumor cells is described. Immunoperoxidase stain for prostatic specific antigen, however, was positive, indicating that this neoplasm was an argyrophilic prostatic carcinoma. Although the clinical significance of a carcinoid-like pattern and/or argyrophilia in prostatic carcinoma is currently unknown, pathologic recognition of these features is of paramount importance because prostatic carcinoma with these features has to be distinguished from true primary prostatic carcinoid tumor or, in areas of metastasis, from metastatic carcinoid originating from other sites such as the gastrointestinal or respiratory tracts. The value of the immunoperoxidase technique for prostatic specific antigen as well as prostatic acid phosphatase in this differentiation is stressed.

Primary signet-ring carcinoma of the colon.

Three cases of primary signet-ring carcinoma, or linitis plastica, of the colon are described. This rare form of colonic carcinoma possesses certain clinical, pathologic, and biologic characteristics that differ from those of the ordinary colorectal adenocarcinoma. Most importantly, the prognosis is poor, with only very few patients surviving more than one year following diagnosis. Some authors believe that the poor prognosis seen with this tumor may be due largely to a delay in diagnosis. Therefore, awareness of this form of colonic malignancy should be stressed so that early recognition may be made at a stage when curative treatment can still be instituted.

Diffuse papillomatosis of the gallbladder.

Herein we document the first case of diffuse papillomatosis of the gallbladder. The lesion occurred in a patient with a history of chronic ulcerative colitis and sclerosing cholangitis with secondary biliary cirrhosis. Of further interest was the presence of Paneth cells in the gallbladder lesion. The unique aspects of this case as well as the significance of papillomas or adenomas of the gallbladder are discussed.