Werner Rosenau

Carcinoma of the thyroid with a mixed medullary and follicular pattern morphologic, immunohistochemical, and clinical laboratory studies

We recently encountered an unusual carcinoma of the thyroid gland with a predominantly medullary pattern admixed with areas of follicular differentiation. Both patterns prevailed at the primary site and in bilateral cervical lymph node metastases. The tumor cells were stained for calcitonin by indirect immunofluorescence technique and were found to contain dense‐core granules by electron microscopy. Calcitonin was demonstrated in tumor homogenates by radioimmunoassay and was elevated in the serum. Immunofluorescence staining also revealed thyroglobulin in the neoplastic cells. Moreover, following total thyroidectomy, the cervical node metastases concentrated radioactive iodine (131I), and serum thyroglobulin was increased at one stage of the disease when measured by radioimmunoassay. These findings are discussed in the light of the dual embryonic derivation of the thyroid gland.

Correlation of dynamic contrast-enhanced magnetic resonance imaging with histologic tumor grade: comparison of macromolecular and small-molecular contrast media

Background. The endothelial integrity of microvessels is disrupted in malignant tumors. Quantitative assays of tumor microvascular characteristics based on dynamic magnetic resonance imaging (MRI) were correlated with histopathologic grade in mammary soft tissue tumors. Materials and methods. A spectrum of tumors, benign through highly malignant, was induced in 33 female rats by administration of N -ethyl-N -nitrosourea (ENU), a potent carcinogen. Dynamic contrast-enhanced MRI was performed using a small-molecular contrast medium [gadopentetate, MW = 0.5 kDa] and a macromolecular contrast medium [albumin-(Gd-DTPA)30, MW = 92 kDa] at an interval of 1–2 days. Permeability surface area product (PS), as estimated by the corresponding endothelial transfer coefficient (KPS), and fractional plasma volume (fPV) were calculated for each tumor and each contrast agent using a two-compartment bi-directional kinetic model. MRI microvascular characteristics were correlated with histopathologic tumor grade. Results. Tumor permeability to macromolecular contrast medium, characterized by KPS, showed a highly positive correlation with tumor grade (r2 = 0.76, P < 10− 10). KPS values were zero for all benign and some low-grade carcinomas, greater than zero in all other carcinomas, and increased in magnitude with higher tumor grade. A considerably smaller but significantly positive correlation was found between fPV and tumor grade using macromolecular contrast medium (r2 = 0.25, P < 0.003). No correlation between KPS or fPV values and tumor grade was found using gadopentetate (r2 = 0.01, P > 0.95 and r2 = 0.03, P > 0.15, respectively). Conclusion. Quantitative tumor microvascular permeability assays generated with macromolecular MRI contrast medium correlate closely with histologic tumor grade. No significant correlation is found using small-molecular gadopentetate.

Contrast-enhanced magnetic resonance imaging estimation of altered capillary permeability in experimental mammary carcinomas after X-irradiation.

RATIONALE AND OBJECTIVES.Dynamic magnetic resonance imaging (MRI) enhanced with a macromolecular contrast medium, albumin-(Gd-DTPA)35, was used to detect changes in microvascular characteristics in R3230 mammary adenocarcinomas induced by x-irradiation. METHODS.Tumors were implanted in either flank in nine rats. One of the tumors was exposed to single-dose x-irradiation (30 Gy) 3 days before MRI. The contralateral control tumor was shielded from irradiation. RESULTS.Capillary permeability to macromolecular contrast medium in irradiated tumors was elevated significantly (P<.05) compared to the control nonirradiated tumors. The mean estimated permeability surface area product for the irradiated tumors increased more than three-fold; 0.511 ± .046 mL hr-1 cm-3 compared with 0.121 ± .011 mL hr-1 cm-3 for the nonirradiated tumors. This radiation-induced increase in permeability was corroborated using a macromolecular Evans blue-protein complex measured in the same tumors using an invasive spectrophotometric technique. CONCLUSIONS.Dynamic MRI-enhanced with macromolecular contrast medium permits noninvasive quantitative estimates of capillary permeability in tumors, with and without xirradiation. Because the transendothelial permeability for macromolecular solutes likely influences tumoral accumulation of macromolecular chemotherapeutic agents, this noninvasive technique may prove to be clinically useful in tailoring tumor treatment programs which combine radiation and chemotherapy.

Cell Proliferation in Prostatic Adenocarcinoma: In Vitro Measurement by 5-Bromodeoxyuridine Incorporation and Proliferating Cell Nuclear Antigen Expression

We assessed cancer cell proliferation, a marker of the biologic activity of tumor cells, by evaluating bromodeoxyuridine (BrdUrd) incorporation and proliferating cell nuclear antigen (PCNA) expression. Prostatic carcinoma specimens (N = 48) were incubated in the presence of BrdUrd to label cells undergoing DNA synthesis, and immunocytochemical staining was performed with monoclonal antibodies to BrdUrd and PCNA and a standard indirect immunoperoxidase technique. The proportion of cells staining positively (labeling index or LI) for BrdUrd and PCNA was determined in 2 ways: by counting only high-power fields with the greatest concentration of stained cells (selected LI); or by counting cells in random fields (random LI). For BrdUrd the mean selected and random LIs were 3.08% and 1.62%, respectively; for PCNA they were 6.02% and 3.47%. Random and selected BrdUrd correlated well (r2 = 0.83), as did random and selected PCNA LIs (r2 = 0.86). However, a weaker correlation was noted when LIs of both techniques were compared, with the PCNA LI usually higher. The LIs of either technique correlated rather poorly with tumor grade and concentration of prostate-specific antigen, but correlated well with clinical stage as assessed by examination and imaging. In addition, either technique discriminated among tumors known to be pathologically confined (stages A and B) and those with extension to seminal vesicles (stage C) or metastatic to regional lymph nodes or bone (p < 0.019).

Forearm Skin Capillaries of Diabetic, Potential Diabetic and Nondiabetic Subjects: Changes Seen by Light Microscope

Light microscopic examinations were carried out on sections of skin from thirty diabetic and 101 control subjects. Examination of the periodic acid-Schiff stained material in a blind study revealed an abnormality in sixteen of the thirty diabetics and seven of the 101 controls. The abnormality is a hyalinization of the normally fibrillar area external to the endothelial cell of the dermal capillaries. Among the diabetics, the abnormality was seen more frequently in juvenile diabetes, long-standing diabetes, diabetes with retinopathy, neuropathy, or nephropathy, and in obese diabetics. The incidence in control subjects was not strikingly higher in those with a family history of diabetes (three in thirty-nine) or in acromegaly (one in eleven) than in other control subjects (three in fifty-one). Electron microscopic observations suggest that the lesion may be due to deposition of material in the collagen containing cuff of the capillary wall rather than to basement membrane thickening.

Comparison of Gadomer-17 and gadopentetate dimeglumine for differentiation of benign from malignant breast tumors with MR imaging.

RATIONALE AND OBJECTIVES This study compared gadopentetate dimeglumine (molecular weight, 0.5 kD), a standard contrast medium, and Gadomer-17 (apparent molecular weight, approximately 35 kD), a new, clinically applicable, large-molecular contrast medium, with respect to their microvascular characterizations of experimentally induced breast tumors at magnetic resonance (MR) imaging. MATERIALS AND METHODS A spectrum of breast tumors, benign through highly malignant, was induced in Sprague-Dawley rats (n = 30) by intraperitoneal administration of N-ethyl-N-nitrosourea (ENU), a potent carcinogen. All animals underwent three-dimensional spoiled gradient-recalled MR imaging, with precontrast imaging and dynamic postcontrast imaging after injection of gadopentetate dimeglumine (0.1 mmol/kg) and Gadomer-17 (0.03 mmol/kg), administered in a random order at a 24-hour interval. Several microvascular parameters were compared: the endothelial transfer coefficient (K(PS)), a measure of microvascular permeability; the fractional plasma volume (fPV), and the plasma equivalent volume. Each MR imaging parameter was correlated with histopathologic findings. RESULTS With Gadomer-17, the mean values for K(PS) and fPV were significantly greater in carcinomas than in fibroadenomas (P < .004 and .04, respectively). With gadopentetate dimeglumine, the mean values for fPV and PEV were significantly greater in carcinomas (P <. 004 and .02, respectively). Because of the high variability within both fibroadenoma and carcinoma groups, however, there were no significant correlations between K(PS), fPV, or PEV and histopathologic tumor grade as indicated by the Scarff-Bloom-Richardson score, for either agent. CONCLUSION Although the K(PS) and fPV estimates obtained from dynamic MR imaging data with Gadomer-17 enhancement offer some potential for characterizing breast tumors, none of the quantitative microvascular parameters derived with either agent were significantly correlated with histopathologic tumor grade.

Lymphotoxin: properties, role and mode of action.

About twenty years ago, studies by Govaerts (1960), Rosenau & Moon (1961) and Rosenau (1963) showed that aggressor lymphocytes from specifically sensitized animals establish direct contact with allogeneic target cells in vitro, which is followed by target-cell lysis. These findings pointed to the essential role of such lymphocytes in cellular immune reactions characterized by cell or tissue destruction. It was subsequently established that the cytotoxic cells are T lymphocytes, which react with specific target cells (Cerrottini, Nordin & Brunner, 1970). Cell lysis appears to proceed in two steps. First, the lymphocytes establish contact with the target cells. This reaction is Ca 2+and Mg2÷-dependent, but fairly independent of temperature (Berke, Sullivan & Amos, 1972; Martz, 1975. The second step does not require the presence of lymphocytes and proceeds effectively only at temperatures near 37°C (Martz & Benecerraf, 1974). Complement does not appear to be involved. For several years, the mechanism of lymphocytemediated lysis remained totally obscure. Ruddle & Waksman (1968), working with lymphocytes derived from tuberculin-sensitized rats, observed a cytotoxic factor in culture supernatants upon addition of purified tuberculoprotein (PPD). That same year, Granger & Williams (1968) found cytotoxic activity in lymphocyte cultures stimulated with the mitogen phytohemagglutinin (PHA). The substance responsible for the cytotoxicity was first called lymphocyte cytotoxic factor, but the term lymphotoxin (LT) subsequently came into general use. Lymphotoxin does not possess target-cell specificity, except that one form, the LT complex, has been reported to associate with immunoglobulin, and may thus perhaps gain specificity (see below). Several investigators have suggested that the specificity of the cytotoxic reaction is related to the ability of specifically sensitized T lymphocytes to recognize and attach themselves to target cells; they then discharge the nonspecific cytotoxin (LT) that accomplishes target-cell lysis. Almost all of the observations on LT have been made in vitro, and there is little information on this lymphocyte mediator (lymphokine) in the intact organism. Two previous reviews have dealt with certain aspects of LT (Rosenau & Tsoukas, 1976; Gately & Mayer, 1978).

Pulmonary oxygen toxicity: Demonstration of abnormal capillary permeability using contrast-enhanced MRI

An animal model of oxygen-induced pulmonary injury was used to assess the potential of contrastenhanced MRI to identify and quantify abnormal capillary permeability. Sprague-Dawley rats were exposed to 100% oxygen for 48 h (n=5) or 60 h (n=9). Axial spinecho MR images were acquired in intubated, anesthetized rats with ECG-gating (TR 400; TE 6) immediately or 7 days after the cessation of oxygen exposure. Polylysine-Gd-DTPA, a macromolecular paramagnetic blood-pool marker, was then given intravenously and the lungs were serially imaged for 42 to 47 min to monitor changes in signal intensity. Pulmonary enhancement was stable in rats exposed to 48 h of oxygen, and in rats exposed to 60 h of oxygen and given 7 days to recover. However, animals exposed to 100% oxygen for 60 h without a period of recovery showed a progressive increase in lung signal intensity for 15 min after polylysine-Gd-DTPA. Pleural effusions also showed progressively increasing signal, reflecting a capillary endothelial leak. A two compartment model describing the kinetics of polylysine-Gd-DTPA in the plasma and interstitial water of the lung was consistent with the dynamic MRI data and allowed estimation of the fractional leak rate (0.235 min−1) of the contrast agent from plasma to interstitial water. Given the assumption of our kinetic model, MRI following intravenous administration of polylysine-Gd-DTPA can be used to quantitate changes in capillary integrity induced by hyperoxia, including acute capillary leakiness and return to normal endothelial integrity with recovery from hyperoxic injury.

Demonstration of α-lymphotoxin in human rejected renal allografts

Abstract To determine whether α-lymphotoxin (α-LT), a lymphokine extensively studied in vitro , can also be isolated from human rejected renal allografts, we developed an isolation procedure by adding LT as a marker to kidney extracts and subjecting the material to a series of protein fractionation techniques. The procedure (without the added marker) was then applied to normal human kidneys and rejected renal allografts. Fractions isolated from normal human kidney were not cytotoxic. However, fractions separated from the rejected grafts were cytotoxic and could be neutralized in part by anti-human α-LT serum. The results of this investigation indicate that human rejected renal allografts, the sites of a mixed cellular and humoral immune reaction, contain α-LT.

MR imaging of liver abscesses; application of Gd-DTPA☆

The potential utility of Gd-DTPA contrast enhancement of MR images in the evaluation of liver abscesses was assessed in rodents. Twelve rats with surgically implanted sterile liver abscesses were imaged at various stages of focal hepatic inflammation, 48 hours, 4 days, 7 days, 14 days and 21 days after lesion induction. Spin echo images, acquired before and repeatedly after intravenous injection of 0.2 mmol/kg Gd-DTPA, demonstrated improvement of the lesion-to-background contrast ranging from 2% to 40% depending on the stage of the disease. The enhancement pattern also varied with abscess evolution. Two, four and seven-day-old abscesses typically showed a ring enhancement, whereas two- and three-week-old abscesses presented largely homogeneously enhancing lesions. In the earlier lesions, contrast enhanced rim surrounding the low intensity center corresponded histologically to the formation of a capsule consisting of fibrous tissue and inflammatory cells. The center was necrotic. Data show that abscesses can be detected on images acquired with long repetition and echo times without injection of Gd-DTPA. The administration of Gd-DTPA, however, improved the lesion-to-background contrast and helped to define the abscess capsule evolution.