Metastatic Renal Cell Carcinoma to the Eye and Adnexae: A Report of Three Cases and Review of the Literature

Three cases of metastatic renal cell carcinoma to the ocular structures are presented. Each of these tumors clinically simulated a more common ocular entity, thus causing diagnostic difficulty. The first patient had a metastatic tumor to the eyelid that clinically simulated a large chalazion. The second patient had a choroidal tumor with clinical features and ancillary studies strongly suggestive of a primary choroidal melanoma. The third patient presented with unilateral proptosis secondary to an orbital mass that was clinically believed to be a cavernous hemangioma of the orbit. In each case, there was a long interval between the initial diagnosis (15 months, 9 years, and 15 years respectively), and the ocular metastasis, which represented the first sign of metastatic disease.     

Preceptor development in residency training through a faculty facilitator

To address the demand for training preceptors, a community hospital-based residency program is using a part-time preceptor in a consultative capacity as a faculty facilitator to model, assess skills, and generally improve the level of teaching. Direct observation of resident-patient interactions and subsequent preceptor critiques are followed by feedback to the preceptor on the cogency and effectiveness of comments made. Goals, objectives, and teaching style are jointly examined by the preceptor and faculty facilitator. Evaluation of videotaped resident-preceptor interactions before and after six months' experience with the faculty facilitator shows significant increases in preceptor skills. Greatest improvement is in comments related to resident's clinical assessments, the resident-patient relationship, and in the quality of the resident-preceptor interaction. Scores by the faculty facilitator are significantly lower but parallel those of an independent, blind evaluator. Preceptor, resident, and administration reactions to the project are all positive. This ongoing program assures the continued upgrading of preceptor skills and provides for faculty attrition. A faculty facilitator providing direct feedback in the clinical setting is a low-cost and viable alternative to workshops and conferences for training effective teachers of family medicine.     

Tumour volume response, initial cell kill and cellular repopulation in B16 melanoma treated with cyclophosphamide and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea.

The relationship between tumour volume response and cell kill in B16 melanoma following treatment in vivo with cyclophosphamide (CY) and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) was investigated. Tumour volume response, expressed as growth delay, was estimated from measurements of tumour dimensions. Depression of in vitro colony-forming ability of cells from treated tumours was used as the measure of tumour cell kill. The relationship between these parameters was clearly different for the two agents studied. CY produced more growth delay (7.5 days) per decade of tumour cell kill than CCNU (2 to 3.5 days). The possibility that this was due to a technical artefact was rejected in favour of an alternative explanation that different rates of cellular repopulation in tumours treated with CY and CCNU might be responsible. Cellular repopulation was measured directly, by performing cell-survival assays at various times after treatment with doses of CY and CCNU which produced about 3 decades of cell kill. The rate of repopulation by clonogenic cells was much slower after treatment with CY than with CCNU, and this appears to account for the longer duration of the growth delay obtained with CY.     

A new method for heterotopic cardiac transplantation in the dog

A new method of heterotopic cardiac transplantation in the dog is described. Transplantation is performed in the thorax using the left innominate artery as an arterial supply with venous drainage into the superior vena cava. Over 200 dogs have undergone heterotopic cardiac transplantation using this technique, which we consider superior to previously described methods in the neck or abdomen. There was no operative mortality and minimal morbidity. Serial electrocardiographic recordings were found to be a more reliable measure of rejection since the donor heart could be compared as a ratio to the voltage of the recipient heart. Biopsy is possible by passage of a flexible cardiac bioptome through the right internal jugular vein and then into the right ventricle of the donor heart. The unpleasant sequelae or heterotopic transplantation in the neck or abdomen (torsion, hematoma, ileus, intestinal obstruction, and intussusception) are avoided.     

Inhibition of human malignant neuroblastoma cell DNA synthesis by lipoxygenase metabolites of arachidonic acid

In vivo studies have shown that inhibitors of cyclooxygenase metabolism of arachidonic acid may diminish growth and metastasis of certain tumors. Because cyclooxygenase inhibition may increase the production of lipoxygenase products of arachidonic acid metabolism, we have investigated the effect of two such products, 12-hydroxyeicosatetraenoic acid (12-HETE) and 15-hydroxyeicosatetraenoic acid (15-HETE) on tumor cell proliferation in vitro. When neuroblastoma cells (SK-N-SH) in culture were treated with 12-HETE for 18 hr, incorporation of [3H]thymidine was inhibited up to 64% at concentrations from 20 to 50 microM. Under the same conditions, 15-HETE resulted in inhibition of up to 46%, while arachidonic acid had no apparent effect. When evaluated in the presence of serum, 12-HETE at a concentration of 120 microM produced a 20.6 +/- 2.8% (S.E.) inhibition of the increase in total DNA content over 48 hr, while 15-HETE at this concentration produced a 16.5 +/- 5.3% inhibition. We conclude that 12-HETE, the product of platelet lipoxygenase, and 15-HETE, a product of neutrophil and lymphocyte lipoxygenases, can inhibit human neuroblastoma cell growth in vitro and may play a role in the effect of cyclooxygenase inhibitors on tumor growth in vivo.     

Does exercise alter anaerobic threshold in coronary artery disease during beta blockade?

The effect of propranolol on cardiac patients undergoing exercise training is reported to increase exercise tolerance and maximum oxygen uptake (VO2 max) but its effect on anaerobic threshold (AT) is unknown. It was the purpose of this study to determine the role of exercise training with propranolol on AT in patients with coronary artery disease (CAD). Eight men and one woman with significant (CAD) were selected for this study. Each patient completed a maximum treadmill stress test (MTST) following the Bruce protocol on propranolol 40-160 mg/day as a control study. Cardiorespiratory variables were measured at rest and at each stage of the treadmill test. These patients underwent an exercise training programme for 12-16 weeks on the same dose of propranolol. Training sessions were for a minimum of 30-40 minutes, 3 times a week, with training heart rate of 75%-85% of the pretraining peak heart rate. Training heart rate ranged from 98 to 128 beats/min. They were retested with a MTST after the training programme, on the same dose of propranolol. AT was calculated noninvasively by measuring respiratory variables every 30 seconds in relation to work increment. AT was identified by measuring the time course of VE, VCO2, VE/VO2, etc. in relation to incremental work. The mean values of VO2, O2P and % VO2 max at AT before and after training on propanolol were as follows: VO2 = 1.43 L/min +/- .25 and 1.86 L/min +/- .44, O2P = 14.35 +/- 2.40 and 18.73 +/- 4.00 ml/beat, % of VO2 max = 68.20 +/- 6.31 and 73.59 +/- 5.84. The mean changes of VO2 O2P, and % of VO2 max were + 0.43 L/min +/- 0.20 (P < .003), + 4.38 +/- 2.55 (P < .003) and +/- 5.07% +/- 4.84 (P < .001). After exercise training on propanolol, the mean peak exercise tolerance time and absolute VO2 max increased by 2.8 min (from 9.0 to 11.8 min) (P < .001) and 22.7% (P < .007), respectively. We conclude that the increase in anaerobic threshold in patients with coronary artery disease may be due to improvement in VO2 max, increased stroke volume, and peripheral O2 extraction.     

Pulsed Doppler angiography in lower limb arterial ischemia.

A 30-channel pulsed Doppler vessel imaging system (MAVIS, GEC Medical, Middlesex, England), was used to obtain images and maximal Doppler velocity time waveforms in the diagnosis of stenosis of the origin of the profunda femoris artery (PFA) and in the detection of structural changes within Dacron arterial grafts. In PFA scans of 33 limbs in 22 patients (mean age, 52 years), PFA stenosis of more than 50% at operation was invariably associated with a damping factor of the maximal Doppler velocity-time waveform of greater than 1.5 (eight limbs). In 12 limbs with a normal PFA at operation, the damping factor was always less than 1.4, and in 13 limbs of normal patients without arterial disease, the damping factor was always less than 1.34. In studies of 10 mm arterial grafts, the internal diameter of 14 iliopopliteal grafts scanned just above the popliteal anastomosis was strikingly reduced as compared with the femoral anastomosis of 14 aortoiliofemoral grafts and seven axillobifemoral grafts. These preliminary results suggest that MAVIS studies can be used noninvasively to detect PFA stenosis and to identify luminal narrowing of iliopopliteal grafts.