Reactive oxygen intermediates increase vascular endothelial growth factor expression in vitro and in vivo

Elevated vascular endothelial growth factor (VEGF) levels are required for ocular and tumor angiogenesis in animal models. Ischemic hypoxia is strongly correlated with increased VEGF expression in these systems and is considered a physiologically relevant stimulus. Because ischemic hypoxia is often followed by reperfusion and reactive oxygen intermediate (ROI) generation, we examined the potential role of ROI in the control of VEGF gene expression. Human retinal pigment epithelial cells exposed to superoxide or hydrogen peroxide rapidly increased VEGF mRNA levels. Superoxide-associated mRNA increases were dose dependent, blocked by antioxidants, and associated with elevated VEGF protein levels in conditioned media. Increases in VEGF mRNA levels were also observed in cultured human melanoma and rat glioblastoma cells with superoxide or hydrogen peroxide. Cycloheximide prevented the ROI-associated increases in VEGF mRNA. Transcriptional inhibition with actinomycin D revealed an inducible increase in VEGF mRNA half-life, but nuclear run-on experiments showed no increase in VEGF transcriptional rate. Reoxygenation of human retinal pigment epithelial cells in vitro and ocular reperfusion in vivo increased retinal VEGF mRNA levels. Antioxidants prevented the reperfusion-associated VEGF mRNA increases in retina. We conclude that ROIs increase VEGF gene expression in vitro and during the reperfusion of ischemic retina in vivo. The ROI-associated increases are mediated largely through increases in VEGF mRNA stability.

Photodynamic therapy of pigmented choroidal melanomas using a liposomal preparation of benzoporphyrin derivative

OBJECTIVE

To evaluate the effectiveness of photodynamic therapy of pigmented choroidal melanoma using a liposomal preparation of benzoporphyrin derivative monoacid (BPD), verteporfin.

DESIGN

Pigmented choroidal melanomas were established in 25 New Zealand albino rabbit eyes. The animals were treated with daily injections of cyclosporine, and tumor growth was monitored with funduscopic examination and ultrasonography. Fifteen minutes after intravenous injection of BPD (2 mg/kg), the tumors were irradiated at 692 nm through an argon-pumped dye laser with the delivered fluence ranging between 40 and 150 J/cm2. Control animals were treated with light only, photosensitizer only, or observation only. Tumor growth was monitored by indirect ophthalmoscopy, fundus photography, fluorescein angiography, and ultrasonography. Histologic examination was performed.

RESULTS

Eighteen tumor-bearing rabbits were treated with light and BPD; 16 were followed up for 1 month, and two were killed immediately for histologic examination. Tumors regressed in all eyes treated with 60 J/cm2 or more. With fluence of 40 J/cm2, tumor regrowth was observed in one animal within 10 days of treatment. In the three control groups, all animals showed continuous tumor growth. Histologic examination of the eyes treated with photosensitizer and light immediately after treatment showed prominent vascular occlusion throughout the full thickness of the tumor. One month after treatment, tumor necrosis and infiltration of mononuclear cells and pigment-laden macrophages were the predominant findings.

CONCLUSIONS

Photodynamic therapy with BPD may have a role in the treatment of pigmented choroidal melanomas.

Radiation oncology at the centennial

1995 marks the centennial year of the discovery of x-rays. The medical profession advanced rapidly following Roentgen's discovery of the x-ray. Every aspect of medicine came to rely on radiology in some way. The x-ray not only revolutionized diagnostic medicine, it transformed therapeutic medicine as well. Only months after its discovery, the x-ray was being used with therapeutic intent, thus began radiation therapy. We can examine the development of radiation oncology in several periods.

An experimental model of retinal pigment epithelial and neurosensory serous detachment

PURPOSE

The authors document an animal model of retinal pigment epithelial (RPE) detachments.

METHODS

N-ethylmaleimide (NEM) and sodium iodate (sulfhydryl-alkylating agents) were injected into the vitreous of Dutch pigmented rabbits. Subretinal fluid samples were withdrawn 0.5 and 3 hours after NEM injections and analyzed for albumin content by gel electrophoresis. Selected eyes were examined histologically.

RESULTS

Injections of 9.2 micrograms NEM caused wrinkling of the retina within 15 minutes, at which time fluorescein angiography revealed multifocal RPE detachments. At this stage, histologic sections showed moderate choroidal edema and RPE detachment. Elevated retinal detachments developed over the next 15 to 25 minutes. Histologic sections showed massive choroidal edema and RPE fragmentation. The albumin concentration of subretinal fluid rose from 60% of serum level at 30 minutes after NEM to 80% after 3 hours. Sodium iodate did not cause choroidal edema or RPE detachment.

CONCLUSION

In rabbits, intravitreal NEM causes the rapid appearance of choroidal edema and RPE detachment, followed by serous retinal detachment. The initial effect probably is caused by an alteration of choroidal vascular permeability. The relationship of these effects to sulfhydryl alkylation is unclear because sodium iodate failed to produce RPE detachments. N-ethylmaleimide effects may model aspects of clinical RPE and serous retinal detachments.

Giant retinal tear and retinal detachment with underlying retinitis pigmentosa and hearing loss

Few retinal detachments have been described in patients with retinitis pigmentosa and allied retinal disorders, with only two cases (both with hearing loss) reported in association with giant retinal tears. To further characterise clinical characteristics of giant retinal tear associated with retinitis pigmentosa, we reviewed the course of four eyes of three patients. Unexpectedly, all three individuals also suffered from congenital sensorineural hearing loss. One suffered from associated myopathy. Despite aggressive surgical management, three of the four eyes became blind. The diagnosis of retinal detachment preceded the diagnosis of photoreceptor dystrophy in two of the three patients. To date, giant retinal tears occurring with underlying retinitis pigmentosa have been described in five young individuals, all of whom had associated congenital sensorineural hearing loss.

The efficacy of cranial irradiation in ovarian cancer metastatic to the brain: analysis of 32 cases

OBJECTIVE

To determine the role of irradiation in the management of brain metastases from epithelial ovarian cancer.

METHODS

Tumor registries from five university cancer centers were searched to identify ovarian cancer patients with brain metastases. During a 30-year period (1965-1994), 4027 ovarian cancer patients were evaluated, 32 of whom were found to have cerebral metastases. Each received fractionated whole-brain irradiation (median dose 30 Gy, range 20-52.5). Five patients received concomitant chemotherapy with whole-brain irradiation.

RESULTS

The median survival time for the whole population was 4 months. For the entire series, symptomatic response (complete response and partial response) was achieved in 23, 16 of whom were palliated until death. Patients with higher Karnofsky performance status (70 or above versus below 70) were more likely to derive a palliative response and attained a statistically significant survival advantage. No other factor predicted the likelihood of deriving a palliative response or a survival advantage after treatment.

CONCLUSIONS

In this large review of patients with cerebral metastases from ovarian cancer, we found that most of those treated with whole-brain irradiation achieved palliation until death. Nearly all women with high performance status derived durable palliation from cerebral irradiation. Whole-brain irradiation was an effective means of palliating ovarian cancer metastatic to the brain and provided a favorable alternative to other means of management.

Twice-per-day fractionated high versus continuous low dose rate intracavitary therapy in the radical treatment of cervical cancer: a nonrandomized comparison of treatment results

PURPOSE

To compare the efficacy of two twice-per-day fractionated high dose rate (HDR) brachytherapies with a historical control group treated with low dose rate (LDR) brachytherapy for cervical cancer patients.

METHODS AND MATERIALS

From 1985 to 1988, 92 patients with cancer of the cervic were treated by remote-controlled, HDR brachytherapy, six fractions of 7 Gy per fraction (42 Gy) at point A (HDR-6). Fifty-seven patients were treated with four fractions of 8 Gy per fraction (32 Gy) at point A (HDR-4). A twice-per-day program was used for all HDR patients by two split courses. As a historical control, treatment results of 259 patients treated with LDR brachytherapy (40 Gy in two split courses) were compared with those of the two HDR regimens. All patients received whole pelvic external irradiation, 36-45 Gy (mostly 40 Gy) before brachytherapy.

RESULTS

Five-year local control rates were not significantly different for the three groups (HDR-6 = 82.0%, HDR-4 = 85.5%, and LDR = 89.5%, respectively). Five-year survival rates were also comparable (67.7%, 77.9%, and 74.1%, respectively). However, late complications were lower in HDR-4 than HDR-6 (11.0% vs. 25.6%).

CONCLUSIONS

Both 5-year local control and survival rates were comparable among the three groups. However, HDR-4, which was more biologically equivalent to our LDR regimen, showed fewer complications compared to HDR-6. In addition, our twice-per-day schedule shortened the hospital stay.

Recurrent acute multifocal placoid pigment epitheliopathy in two cousins

PURPOSE/METHODS

To test the hypothesis that there may be inherited predisposition in acute multifocal placoid pigment epitheliopathy, HLA typing was undertaken in two cousins with recurrent disease.

RESULTS/CONCLUSIONS

Both cousins were shown to have HLA antigens DR2 but not B7; both antigens have been associated with this disorder previously. This finding is compatible with the concept that DR2 may be associated with an increased risk of recurrent disease.

Major geometric variations between multiple high-dose-rate applications of brachytherapy in cancer of the cervix: frequency and types of variation

PURPOSE

To evaluate major geometric variations in multiple intracavitary applications for carcinoma of the cervix.

MATERIALS AND METHODS

Orthogonal radiographs were reviewed of 17 consecutive patients with carcinoma of the cervix treated with 70 applications of high-dose-rate brachytherapy. In seven patients, conscious sedation was used for all applications. In 10 patients, general anesthesia was used for the first application and conscious sedation for subsequent applications. Major geometric variation between applications in axis, length, and slippage in tandem placement and separation, packing, and slippage in colpostats placement were reviewed. A major variation was defined as more than 1.0-cm deviation.

RESULTS

Major variations between applications occurred more commonly in colpostats placement than in tandem placement. For tandems, the rates of variation were 5.7% in axis, 4.3% in length, and 1.4% in slippage. For colpostats, rates of variation were 7.1% in separation, 25.7% in vaginal packing, and 7.1% in slippage. No consistent pattern of variation was found between applications except in vaginal packing.

CONCLUSION

Awareness of geometric variations should improve proper placement of intracavitary applicators for brachytherapy.

Autosomal dominant pattern dystrophy of the retina associated with a 4-base pair insertion at codon 140 in the peripherin/RDS gene

OBJECTIVE

To define the phenotype of a retinal dystrophy associated with a 4-base pair insertion at codon 140 of the peripherin/RDS gene.

PATIENTS

Six affected members spanning two generations of a single family were examined. Five were studied in detail electrophysiologically and psychophysically.

METHODS

Psychophysical testing included color vision testing, photopic and scotopic static threshold perimetry, and dark adaptometry. Electrophysiological testing included flash and pattern electroretinography, as well as electrooculography.

RESULTS

Clinical findings ranged from subtle pigmentary changes at the level of the retinal pigment epithelium to more widespread pigmentary changes associated with choroidal neovascularization. Those with severe fundus changes exhibited greater abnormalities in psychophysical and electrophysiological testing than those with minimal fundus changes.

CONCLUSIONS

This particular peripherin/RDS gene mutation is associated with dominantly inherited pattern dystrophy of the retina. The phenotypic expression is variable in a manner not explained by age.

Autosomal dominant retinitis pigmentosa mapping to chromosome 7p exhibits variable expression

The genetic locus causing autosomal dominant retinitis pigmentosa (adRP) has recently been mapped in a large English family to chromosome 7p. Eight affected members of this family were studied electrophysiologically and psychophysically with dark adapted static threshold perimetry and dark adaptometry. The phenotypes observed fell into three categories: minimally affected with no symptoms, and normal (or near normal) electrophysiology and psychophysics; moderately affected with mild symptoms, abnormal electroretinograms, and equal loss of rod and cone function in affected areas of the retina; and severely affected with extinguished electroretinograms and barely detectable dark adapted static threshold sensitivities. The mutation in the gene on 7p causing adRP in this family causes regional retinal dysfunction with greatly variable expressivity ranging from normal to profoundly abnormal in a manner not explained by age.

Conventional four-field pelvic radiotherapy technique without computed tomography-treatment planning in cancer of the cervix: potential geographic miss and its impact on pelvic control

PURPOSE

To evaluate the impact of inadequate margins on pelvic control using the conventional four-field pelvic portals without computed tomography (CT)-treatment planning.

METHODS AND MATERIALS

Between 1986 and 1991, 34 patients with invasive cancer of the cervix were eligible for outcome study of conventional four-field radiation therapy (10 Stage I, 16 Stage II, 8 Stage III). The eligibility for this study includes four-field pelvic technique, definitive radiation therapy, and diagnostic CT scan of the pelvis. For this study, an inadequate margin is arbitrarily defined as < or = 1.0 cm of normal tissue around the CT-defined tumor volume.

RESULTS

All 34 patients had adequate margins for anterio-posterior/posterio-anterior portals. However, 19 patients had an inadequate margin at the posterior border (S2-S3 interspace) and/or custom-shaped rectal block for lateral pelvic portals. Two patients had inadequate margins at the anterior border (level of symphysis pubis) due to an enlarged uterus. With a median follow-up of 36 months, pelvic control for adequate margins and inadequate margins was 100% and 71% for Stage IB disease and 88% and 50% for Stage IIB disease, respectively. However, pelvic control for Stage IIIB disease was 50% for both groups. There was no difference in total dose to point A or point B between the two groups.

CONCLUSION

Our preliminary data show higher local failure in patients with an inadequate margin. For four-field pelvic radiation therapy, we strongly recommend CT-treatment planning. Otherwise, anterio-posterior/posterio-anterior pelvic therapy is the most reliable treatment for cancer of the uterine cervix.

Cutaneous melanoma-associated retinopathy

PURPOSE

To define further the syndrome of cutaneous melanoma-associated retinopathy, of which only five affected patients have been reported previously.

METHODS

Three men with melanoma-associated retinopathy were examined and studied electrophysiologically. Two were studied in detail psychophysically.

RESULTS

Visual symptoms consisted of flickering black and white spots, shimmering patches of colors, and night blindness. The onset was acute and nonprogressive. Reduced amplitudes were observed in the flash electroretinographic b-wave and the pattern electroretinogram. Color vision, contrast sensitivity, and light- and dark-adapted perimetric sensitivities were abnormal. In one patient, the rate of dark adaptation was normal with elevated final cone and rod thresholds.

CONCLUSIONS

Melanoma-associated retinopathy is a paraneoplastic syndrome distinct from cancer-associated retinopathy with a different visual prognosis. It may preferentially affect men.

A clinically practical electron cone for the treatment of head and neck cancer

PURPOSE

The purpose of the work was to develop a practical electron cone and to compare its dosimetry with that of the conventional applicator collimation system.

METHODS AND MATERIALS

The electron cone consists of the upper part of a manufacturer-supplied electron applicator and an institution-built rectangular extension tube which produces a 12 cm x 6 cm field at 100 cm SSD while maintaining an air gap of 5 cm between the patient.

RESULTS

The compact size of the cone allows electron irradiation without having to reposition the patient after photon treatment. The radiation field is very similar to that of a standard 15 cm x 15 cm applicator with a 12 cm x 6 cm field restricting insert. Radiation leakage at the surface of the special cone is typically less than 1% of the useful beam at dmax. During 12 years of clinical use the special cone proved itself very practical in the treatment of more than 300 patients.

CONCLUSION

An electron cone practical for clinical use with dosimetry comparable to the conventional applicator was developed.

Conventional four-field pelvic radiotherapy technique without CT treatment planning in cancer of the cervix: potential geographic miss

The advantage of 4-field radiation to the pelvis is the use of lateral ports which spare the small bowel anteriorly and a portion of the rectum posteriorly from radiation. However, guidelines for the lateral pelvic ports are poorly defined. This is a comparative analysis to determine adequate margins by correlating conventional lateral pelvic treatment portals with CT defined tumor volume. The study included 52 patients treated definitively for carcinoma of the uterine cervix between 1986 and 1991. The most common site of inadequate margin (< or = 1.0 cm) was at the rectal block. The incidence of inadequate margin ranged from 39% to 50% and was independent of the stage of the disease except non-bulky stage IB disease. The next most common site was at the posterior border where frequency of inadequate margin for cervical tumor depended on stage with 8% of stage IB, 27% of stage IIB and 22% of stage IIIB/IVA disease. For the anterior border, an enlarged uterus was the only reason for inadequate margin rather than cervical tumor in 8% of stage IB, 18% of stage IIB, and 27% of stage IIIB/IVA disease. Without knowledge of precise tumor volume, the 4-field pelvic technique is potentially dangerous, risking underdosing of the tumor volume. For 4-field pelvic radiotherapy, we strongly recommend CT treatment planning.

Age and radiation sensitivity of rat mammary clonogenic cells

The relative risk of breast cancer is very high among women who were exposed to ionizing radiation during or before puberty. In the current studies, the surviving fractions of clonogenic mammary cells of groups of virgin rats were estimated after single exposures to 137Cs gamma rays at intervals from 1 to 12 weeks after birth. The radiosensitivity of clonogens from prepubertal rats was high and changed with the onset of puberty at between 4 and 6 weeks of age. By this time, the increase in the size of the clonogenic cell subpopulation was slowing and differentiation of terminal mammary end buds and alveolar structures was occurring. Analysis of the relationship of clonogen survival and radiation dose according to the alpha/beta model showed that the exponential alpha D term predominated at the second and fourth weeks of age. By the eighth week of age, the beta D2 term had come to predominate and the survival curve had a pronounced initial convex shoulder. Further experiments are required to determine whether there is an association between the high sensitivity of the prepubertal and pubertal mammary clonogens to radiation killing and a high susceptibility to radiogenic initiation of cancer.

Acute zonal occult outer retinopathy (AZOOR) associated with multifocal choroidopathy

Acute zonal occult outer retinopathy (AZOOR) may be precipitated by various retinal disorders and is characterised by rapid loss of visual field which cannot be explained by the ophthalmoscopic changes consequent upon the initiating disease. The electroretinogram is abnormal, indicating that the field loss is due to retinal dysfunction. The phenomenon was first recognised in the multiple evanescent white dot syndrome (MEWDS) as the enlarged blind spot syndrome. It was subsequently described with multifocal inner choroidopathy and acute macular neuropathy (AMN). We have identified 7 patients who presented with widespread visual loss associated with multifocal inner choroidopathy in whom functional loss was documented with electroretinography and automated visual field testing. All patients were young, myopic, and otherwise healthy women. Initial photopsia was noted by 4 patients. Fundus findings included scattered small partially pigmented yellowish lesions resembling those in multifocal inner choroidopathy or pseudo presumed ocular histoplasmosis syndrome, disc swelling, vitritis, and secondary choroidal neovascularisation. Two patients had bilateral involvement. All patients had an enlargement of the blind spot, and widespread visual field loss which was not explained by fundus changes. All had an abnormal electroretinogram suggesting widespread retinal disease. In AZOOR retinal dysfunction occurs without corresponding visible retinal lesions. This disorder appears to be precipitated by several conditions, although the causal relationship between the initiating event and the widespread functional loss is unknown.

Malignant epidural spinal cord compression associated with a paravertebral mass: its radiotherapeutic outcome on radiosensitivity

PURPOSE

To evaluate clinical characteristics and functional outcome of malignant epidural spinal cord compression associated with a paravertebral mass.

METHODS AND MATERIALS

Between 1987 and 1990, 136 patients with epidural spinal cord compression were treated with irradiation. Of these, 25 patients (18%) had epidural spinal cord compression associated with a paravertebral mass. This report is based on analysis of these 25 patients. Fourteen patients received 3000 cGy in 10 fractions. Seven received 4000 cGy in 16 fractions. Four received 2000 cGy in 5 fractions. Motor function was evaluated by five grades.

RESULTS

Lung cancer accounted for the majority of epidural spinal cord compression with a paravertebral mass (60%) followed by lymphoma (8%) and kidney tumor (8%). This pattern of epidural spinal cord compression has a longer duration of pain before developing neurologic symptoms and has a high propensity of the upper thoracic spine involvement by an apical lung cancers. The functional outcome of radiation treatment reveals a significant difference between moderately radiosensitive tumors (lung, prostate, cervix, esophagus) and very radiosensitive tumor (lymphoma). None of the nonambulatory patients became ambulatory following radiotherapy except for the very radiosensitive tumors. Higher doses of radiation treatment (4000 cGy in 16 fractions) did not improve functional outcome.

CONCLUSION

Due to the larger tumor burden, radiation treatment for epidural spinal cord compression associated with a paravertebral mass is not as effective as treatment of epidural spinal cord compression without a paravertebral mass except for the very radiosensitive tumor. Therefore, combined treatment modality might be beneficial for improving functional outcome.

Dominant retinitis pigmentosa associated with two rhodopsin gene mutations. Leu-40-Arg and an insertion disrupting the 5'-splice junction of exon 5

OBJECTIVE

To determine the phenotypes of two families in which retinitis pigmentosa cosegregates with a rhodopsin (RHO) gene mutation: a leucine-to-arginine change at codon 40 (Leu-40-Arg) in one family, and a 150-base pair insertion that disrupts the RHO 5'-splice junction of exon 5 in another.

PATIENTS

Three affected members of each family.

RESULTS

The Leu-40-Arg mutation was associated with the onset of night blindness in the first decade of life. By the fourth decade, severe retinal functional loss was evident on dark-adapted static threshold perimetry, and electroretinographic responses were absent or barely detectable. In contrast, the RHO 150-base pair insertion was associated with the later onset of mild night vision difficulties; in two individuals, mild night vision difficulties were first noticed in the second decade while a third, a 25-year-old woman, was asymptomatic. Dark-adapted static threshold perimetry of this latter individual revealed a "regional" or class 2 pattern of retinal functional loss associated with equal loss of rod and cone electroretinographic responses.

CONCLUSION

The RHO Leu-40-Arg mutation causes symptomatic retinal dysfunction by the end of the first decade while the insertion disrupting the 5'-splice junction of RHO exon 5 causes later onset "regional" or class 2 retinal dysfunction.

An avian alpha B-crystallin. Non-lens expression and sequence similarities with both small (HSP27) and large (HSP70) heat shock proteins

alpha B-crystallin is multifunctional, serving as both a major structural protein in the lens and a small heat-shock protein (shsp) in other tissues in mammals. Cloning and Northern analysis show similarly that alpha B-crystallin mRNA is present in all mature tissues examined in a bird (Anas platyrhynchos), although there are some differences in the pattern of transcripts seen. Interestingly, sequence analysis not only shows that duck alpha B-crystallin is a member of the shsp family, as expected, but that this family shares more distant similarity with another heat shock protein family, the highly conserved HSP70s of both eukaryotes and prokaryotes. This raises the possibility that large and small hsps may share structural and perhaps functional features.

Oxygen dependency of retinal adhesion

PURPOSE

Normal retina is firmly attached to the retinal pigment epithelium, but the force of this adhesion drops precipitously within the first 2-3 min after enucleation. The purpose was to study metabolic factors that might be relevant to this postmortem failure of adhesion.

METHODS

Dutch rabbit retina was manually peeled from the retinal pigment epithelium on strips of enucleated eyecup within a 37 degrees C bath. Retinal adhesiveness was measured by observing the amount of retinal pigment epithelium that remained adherent to the retina.

RESULTS

Autologous whole blood in place of salt solution retarded the decrease in adhesiveness. A solution of hemoglobin alone was similarly effective, whereas methemoglobin solution failed to help the persistence of retinal adhesion. Bubbling oxygen into the salt solution and circulating it to avoid oxygen depletion at the tissue boundary also proved effective at sustaining retinal adhesiveness. Eyes made ischemic in vivo for 5 min or longer, by elevating intraocular pressure, showed virtually no retinal adhesion when enucleated immediately thereafter. However, eyes made ischemic for 10 min, but allowed to regain circulation for 5 min before enucleation, showed a return of retinal adhesiveness to 80% of normal.

CONCLUSIONS

Oxidative metabolism is critical to the maintenance of retinal adhesiveness, and the effects of oxygen deprivation on adhesion are reversible within a certain time period.

Expression of the duck alpha-enolase/tau-crystallin gene in transgenic mice

In many vertebrates, metabolic enzymes have been directly recruited to an additional structural role as crystallins in the eye lens. In some species the glycolytic enzyme alpha-enolase (alpha ENO) attains high concentrations in the lens, as tau-crystallin (tau CRY). A line of transgenic mice was constructed containing the entire duck alpha ENO/tau CRY gene with 5'- and 3'-flanking regions and all introns. Full-sized duck alpha ENO mRNA was expressed in the transgenic mice with the same pattern as the endogenous mouse alpha ENO isozyme. Although there was no evidence for tissue preference, the concentration of enolase increased markedly in transgenic lens as well as in other tissues. In spite of this, transgenic lenses were transparent and the animals were normal in appearance. The increase in enolase levels in the transgenic lens mimics the stepped increase that might occur in the early stages of enzyme crystallin recruitment. These results demonstrate that lens transparency is sufficiently robust to be refractory to some increase in metabolic enzyme concentration without the need for compensatory adaptation.

A phase I study of high-dose cisplatin, prolonged infusion 5-fluorouracil, and concomitant conventional fraction radiation therapy in patients with inoperable squamous cell carcinoma of the head and neck

Cisplatin (CDDP) and 5-fluorouracil (5-FU) have been used alone, in combination, and in various doses and sequences with radiation therapy in attempts to improve local control and survival of patients with advanced head and neck cancer. This study was undertaken to determine the toxicity and maximum tolerated dose of high-dose CDDP plus prolonged infusion 5-FU with concomitant conventional radiation therapy. Twenty-two patients with inoperable Stage III and IV squamous cell cancer were treated with CDDP (30 or 35 mg/m2 for 5 days every 4 weeks for three courses) and 5-FU (200 or 300 mg/m2 per day continuous i.v. infusion for 12 weeks) with concomitant conventional radiation therapy. This aggressive treatment regimen is accompanied by severe mucositis, myelosuppression, and chronic neuropathy. CDDP, 35 mg/m2/day x 5, and 200 mg/m2/day of 5-FU infused over 12 weeks were identified as potential doses for future Phase II studies.

The cDNA RPE1 and monoclonal antibody HMB-50 define gene products preferentially expressed in retinal pigment epithelium

As a first step towards identifying genes expressed specifically in the retinal pigment epithelium (RPE), we generated a bovine RPE cDNA library. In preliminary characterization of this library, we isolated a clone, RPE1, that was identified as the bovine homologue of a human cDNA thought to encode the HMB-50 melanoma antigen. Sequence analysis suggests RPE1 encodes a membrane-anchored glycoprotein. In Northern blot analysis of RNA from bovine tissues, the 2.5 kb RPE1 transcript was detected only in the RPE. Southern blot analysis suggested the presence of a single bovine rpe1 gene. In normal human eyes, HMB-50 immunoreactivity was also restricted to the RPE; no immunoreactivity was detected in other intraocular pigmented cells. Thus, RPE1 and HMB-50 define gene products preferentially expressed in the RPE at the RNA and protein levels, respectively.

mu-crystallin is a mammalian homologue of Agrobacterium ornithine cyclodeaminase and is expressed in human retina

mu-Crystallin is the major component of the eye lens in several Australian marsupials. The complete sequence of kangaroo mu-crystallin has now been obtained by cDNA cloning. The predicted amino acid sequence shows similarity with ornithine cyclodeaminases encoded by the tumor-inducing (Ti) plasmids of Agrobacterium tumefaciens. Until now, neither ornithine cyclodeaminase nor any structurally related enzymes have been observed in eukaryotes. RNA analysis of kangaroo tissues shows that mu-crystallin is expressed at high abundance in lens, but outside the lens mu-crystallin is preferentially expressed in neural tissues, retina, and brain. An almost full-length cDNA for mu-crystallin was cloned from human retina. In human tissues, mu-crystallin mRNA is present in neural tissue, muscle, and kidney. This pattern of expression and relationship to an enzyme involved in unusual amino acid metabolism suggests the interesting possibility that mammalian mu-crystallins could be enzymes participating in processes such as osmoregulation or the metabolism of excitatory amino acids.

Early-stage glottic cancer: importance of dose fractionation in radiation therapy

The treatment results in 85 patients with T1N0M0 squamous cell carcinoma of the glottic larynx who were treated with primary radiation therapy were reviewed to analyze for local control. After a minimum follow-up period of 2 years, 13 patients had local recurrence of disease, which yielded a local control rate of 84.7%. Local control was then reassessed as a function of substages (T1a and T1b) and dose fractionation. No difference in local control was seen in T1a and T1b neoplasms. However, after undergoing standard once-a-day fractionation, patients treated with fractions of 200 cGy had a local control rate of 96%, while those receiving 180 cGy had a local control rate of 79% (P = .05). Mean total dose for each patient group was comparable, and the median number of days of treatment interruption was the same for both groups. These data corroborate the recent findings of other authors regarding the importance of fraction size in facilitating local control of early-stage glottic cancer.

Treatment of recurrent head and neck cancer with 5-fluorouracil, hydroxyurea, and reirradiation

Head and neck cancer locally recurrent after previous irradiation and surgery presents a difficult management problem. Conventional treatment alternatives include chemotherapy, reirradiation with interstitial implant, and hyperthermia. Reirradiation with external beam is generally not considered because of previous high radiation dose and limited tissue tolerance. In this study, 21 patients with recurrent and previously irradiated head and neck cancer were treated in a Phase I-II fashion. Patients received 5 days of 5-fluorouracil, 300 mg/m2/day IV bolus, Hydroxyurea 1.5 or 2 g/day by mouth and external beam radiation therapy every 2 weeks for up to four courses. Of 20 evaluable patients, 9 have attained a complete response (CR) and 6 a partial response (PR). Fifteen patients completed all planned therapy, eight on time, seven patients with delays. With a median follow-up of 7 months, 13 patients are alive, 7 disease-free (3 after salvage surgery) and 6 with recurrence. Eight patients have died. The 1-year survival is 56%. Treatment toxicity was mainly neutropenia. No major early or late radiation related side effects have been observed at a median follow-up of 7 months. Neither previous radiation dose, time since first radiation, prior chemotherapy, or site of recurrence was predictive of response or treatment tolerance. Patients with a performance status of at least 80 had a significant higher CR rate, with 7/10 patients in this group, as compared to 2/10 patients in patients with a performance status less than 80, achieving a CR. Reirradiation with 5-fluorouracil and hydroxyurea is a well tolerated outpatient treatment program for patients with recurrent and previous irradiated head and neck cancer that produces a high response rate and can provide significant palliation of symptoms.

Independent segregation of fundus albipunctatus and the transthyretin (prealbumin) gene

A defect in the visual cycle has been suspected in patients with fundus albipunctatus (FALB), rendering genes encoding visual cycle components etiologic candidates. One such component is the retinoid and thyroxine transport protein transthyretin (TTR, prealbumin) which in the eye is synthesized only in the retinal pigment epithelium and is believed to play a role in retinal retinoid transport. The authors established polymerase chain reaction conditions that allow rapid assay of TTR alleles as defined by MspI and Fnu4HI restriction fragment length polymorphisms. In a candidate gene analysis of an affected family, they demonstrate independent segregation of the TTR and FALB disease loci. These results exclude the possibility that a TTR gene defect causes FALB in this family.

Three-port perineal sparing technique

The records were reviewed of 103 patients with low-lying pelvic malignancies irradiated with a skin-sparing technique involving use of a pair of anteroposterior-posteroanterior opposed ports and a direct perineal port. Patients had rectal, anal, cervical, vaginal, urethral, or vulvar cancer. Use of a special lead compensator allowed the three beams to be applied perpendicularly to the surface, while delivery of a homogeneous dose to the pelvis and perineum was maintained. Skin dose with this method was greatly reduced compared with that delivered with simple opposing or four-port techniques, in which irradiation is tangential to the surface at the perineum. Acute perineal skin irritation was assigned a grade between 0 and 3, with grade 0 representing the least amount of irritation. All patients were in the grade 0 or grade 1 category. Patients treated for low-lying rectal carcinoma showed no increase in perineal recurrences when compared with historic control subjects. Use of this approach allowed delivery of adequate doses to the pelvis and perineum and a definite decrease in local toxic effects, and local control was not compromised.

Structure and expression of the duck alpha-enolase/tau-crystallin-encoding gene

In the duck, the glycolytic enzyme, alpha-enolase (alpha ENO) and the lens structural protein, tau-crystallin (tau CRY), are products of the same gene, an example of protein multi-functionality. We report that duck alpha ENO/tau CRY mRNA levels are developmentally regulated: alpha ENO/tau CRY mRNA levels in the lens increase over those in the liver by embryonic day 14 and, within the lens, are higher in the lens epithelium than in fiber cells. We determined the structure of the duck alpha ENO/tau CRY-encoding gene (alpha ENO/tau CRY), sequenced 1 kb of 5'-flanking region, and demonstrated that this region contains a functional promoter. The gene is 13 kb in size and is composed of twelve exons; the exon organization is identical to that of mammalian enolase-encoding genes. A fragment of 5'-flanking region (-803/+3) containing three CCAAT boxes and a TATA box was able to activate transcription of a heterologous reporter gene when transfected into cultured lens cells. However, in spite of greater quantities of alpha ENO/tau CRY mRNA and protein in the lens, the promoter was equally active in primary cultures of embryonic lens, liver and fibroblast cells. Since the cultured cells unexpectedly lost the restricted pattern of alpha ENO/tau CRY mRNA levels observed in vivo, evaluation of the promoter's tissue specificity was precluded.

A phase I study of prolonged infusion 5-fluorouracil and concomitant radiation therapy in patients with squamous cell cancer of the head and neck

The radiosensitization properties of 5-FU are well documented, and clinical trials have suggested improved local control and survival in head and neck cancer. Clinical trials to date have used bolus injection or short term (less than or equal to 5 days) 5-FU infusions. To determine the maximum tolerated dose (MTD) of 5-FU given as continuous intravenous infusion for 12 weeks concomitant with conventional radiation therapy, 18 patients with advanced inoperable head and neck cancers were treated with conventional irradiation and 100, 200, 250, or 300 mg/m2/day of 5-FU. A dose of 250 mg/m2/day was determined to be the maximum tolerated dose and is recommended for Phase II studies.

Extradural spinal cord compression from metastatic tumor

Extradural spinal cord compression (ESCC) as a consequence of metastasis from various primary cancers represents the most common type of malignant lesion affecting the spinal cord. It has been estimated that 5% of all patients with systemic cancer who are autopsied have pathologic evidence of tumor invading the extradural space. The incidence of ESCC is expected to increase due to improved survival of the cancer patient. The current approach to the diagnosis of ESCC depends upon the recognition of early symptoms and signs of spinal cord compression. Despite the increasing clinical awareness of these complications, irreversible loss of ambulation continues to occur in over half of these patients. Early diagnosis is critical since onset of spinal cord injury may be sudden, often progressing to irreversible paralysis in a period of hours. Consequently, physicians dealing with cancer patients must maintain a high index of suspicion. This paper analyzes prognostic factors based on our prospective study and emphasize the use of diagnostic tests in early recognition of ESCC before onset of neurologic deficits.

Extradural spinal cord compression: analysis of factors determining functional prognosis--prospective study

The treatment results in 59 patients with extradural spinal cord compression (ESCC) who were treated with irradiation between April 1987 and December 1988 were analyzed prospectively. Eighty percent of the patients presented with back pain, which preceded ESCC by an average of 6 weeks. The most common primary tumor was lung cancer (27% of cases), followed by prostate cancer and breast cancer. The prognostic significance of pretreatment motor function, degree of spinal cord block, radiosensitivity of tumor, and radiation dose schedule was determined with multivariate analysis. Only pretreatment motor function was found to be a significant factor in determining functional prognosis (P = .0058). Even with the increasing clinical awareness of ESCC, 78% of the patients in the current series were nonambulatory at presentation. Therefore, computed tomographic myelography or magnetic resonance imaging is recommended for patients with back pain and bone destruction at the site of the complaint if local radiation treatment is not planned.

Retinoids and butyrate modulate fibroblast growth and contraction of collagen matrices

Wound healing in the eye may lead to undesirable sequelae such as proliferative vitreoretinopathy and scarring of glaucoma filtering fistulas. We therefore sought to manipulate in vitro two key wound healing processes--cell proliferation and contraction of extracellular matrices--using vitamin A (VA), retinoic acid (RA), and n-butyrate (BUT). These substances modulate growth and differentiation of normal and neoplastic cells. We examined the effects of these agents on cultured rabbit fibroblast proliferation and contraction of collagen matrices. Dermal fibroblast proliferation was unaffected by VA, stimulated by RA, and inhibited by BUT. Scleral fibroblast proliferation, in contrast, was stimulated by both VA and RA. All three agents mildly inhibited fibroblast contraction of collagen matrices. We conclude that 1) VA, RA, and BUT have differential effects on rabbit fibroblast proliferation; 2) retinoid effects on fibroblast growth vary with the tissue of origin; and 3) VA, RA, and BUT modestly inhibit fibroblast contraction of extracellular matrices. This study suggests that fibroblast-mediated processes in ocular wound healing and cicatricial disease may be differentially modulated by retinoids and BUT.

Radiotherapy as an adjunct in the management of Merkel cell carcinoma

Four patients with a diagnosis of Merkel cell carcinoma initially underwent surgery followed by radiotherapy. Recurrent disease prompted use of radiation in three cases. The three cases of recurrent disease illustrate the aggressiveness of Merkel cell carcinoma and also provide further documentation of the radiosensitivity of this tumor. Additionally, these cases suggest that surgery alone frequently is inadequate to achieve local control of disease.

Radiation alone in the treatment of cancer of the uterine cervix: analysis of pelvic failure and dose response relationship

This retrospective analysis involves 569 patients with invasive cancer of the uterine cervix treated with irradiation alone between 1969 and 1980. Treatment consisted of external and intracavitary irradiation and treatment policy remained consistent throughout the study interval. In early stage disease (FIGO IA, IB, and IIA), pelvic failure was 4.6%, 11.2%, and 8.2%, respectively. In late stage disease (FIGO IIB, III, and IVA), pelvic failure was 30.1%, 52.3%, and 69.2%, respectively. Further analysis revealed that total dose at point A is well correlated with pelvic control. An aggressive treatment is crucial in late stage disease in determining the probability of pelvic tumor control and survival. Methods of dose prescription, dose-response relationships, treatment philosophy and its therapeutic implications are discussed.

Superior segmental optic hypoplasia. A sign of maternal diabetes

In a review of 10 patients with superior segmental optic nerve hypoplasia, all of whom were the children of diabetic mothers, 17 of 20 eyes had one or more of four characteristic findings in the optic disc: relative superior entrance of the central retinal artery, pallor of the superior disc, superior peripapillary halo, and thinning of the superior peripapillary nerve fiber layer. We believe that the presence of these four signs of superior segmental optic nerve hypoplasia strongly suggests maternal diabetes.

Intraperitoneal chromic phosphate in ovarian cancer: risks and benefits

Between March 1977 and December 1985, 59 patients were treated with intraperitoneal chromic phosphate at The University of Alabama Birmingham Hospitals and its affiliates. Twenty-seven patients received primary adjuvant therapy. Thirty-two patients were treated "secondarily" after tumor recurrence or after a "positive" second-look laparotomy. Associated morbidity was noted to be 12% with reoperation required in 7%. Early stage and grade tumors demonstrate a good prognosis. Little, if any, benefit was demonstrated in "secondary" therapy of advanced stage and grade tumors.

Analysis of treatment modalities and their failures in stage IB cancer of the cervix

This is a retrospective analysis of 240 patients who had clinical Stage IB cancer of the cervix treated with radiation between 1969 and 1980. Of these, 186 patients were treated with a combination of external and intracavitary radiation therapy, and 54 patients received adjuvant postoperative radiation therapy. The minimum follow-up was 5 years. In the group who received only radiation therapy, the overall recurrence in 170 patients (excluding 16 patients found at laparotomy to have unresectable disease) was 17% (29 of 170); pelvic recurrence was 9% and distant metastases alone was 6%. In the group who received the adjuvant postoperative radiation therapy, 16 patients had a simple hysterectomy followed by vaginal ovoid and/or external pelvic irradiation for an unexpected Stage IB cancer of the cervix. Their overall recurrence was 37.5% (6 of 16). Pelvic recurrence was the most common treatment failure with a recurrence of 31%. Significant prognostic factors were depth of stromal invasion and status of surgical margins. Thirty-eight patients had a radical hysterectomy followed by postoperative radiation therapy because of positive pelvic lymph nodes and/or close surgical margins. In patients with positive pelvic lymph nodes, the overall recurrence was 39% (9 of 23); pelvic recurrence was 13%. Distant metastases, the most common treatment failure, was 26%. In seven patients with close surgical margins, five recurred in the pelvis. There was no distant metastases without pelvic failure. Five of eight patients with close paracervical margins recurred in the pelvis. All five of these patients were treated with vaginal ovoid irradiation alone. Whole pelvic irradiation plus vaginal ovoid irradiation is necessary in those with close paracervical margins. The vaginal ovoid irradiation alone should be limited to very selected patients with positive vaginal margins only.

Adjuvant postoperative radiation therapy following radical hysterectomy in stage IB CA of the cervix--analysis of treatment failure

Among 240 patients treated by radiation therapy for clinical Stage IB cancer of the cervix between 1969 and 1980, 38 patients received postoperative pelvic radiation therapy after radical hysterectomy because of positive pelvic lymph nodes and/or close surgical margins. The overall recurrence was 45% (17 of 38), and the major complication rate was 15% in minimum 5-year follow-up. In patients with positive pelvic lymph nodes, the pelvic recurrence was 13% (3 of 23). However, distant metastases alone was 26% (6 of 23), which was the most common treatment failure. In 11 patients with close surgical margins, eight patients had paracervical margins and three had vaginal margins. All five patients with paracervical margins treated with vaginal ovoid irradiation only had pelvic recurrence. No local failure occurred in the other three patients treated with whole pelvic irradiation. All patients with vaginal margin alone treated with vaginal ovoid or whole pelvic irradiation had no recurrence of cancer in the pelvis. On the basis of our data, whole pelvic irradiation with or without vaginal ovoid irradiation is necessary in those with a close paracervical margin. In patients with close vaginal margin, whole pelvic irradiation with or without vaginal ovoid irradiation is recommended. The vaginal ovoid irradiation alone should be limited to very selected cases.

Skeletal metastases from cancer of the uterine cervix: frequency, patterns, and radiotherapeutic significance

The records of eight hundred two patients who received primary radiotherapy for invasive cervical cancer between 1969 and 1985 were reviewed. The incidence of bone metastasis was 1.9% (15/802). Lumbar spine involvement was the most common site, followed by the pelvic bones. Lumbar spine involvement was characterized by unilateral destruction of one or several contiguous vertebrae. All 10 patients with lumbar spine involvement were associated with a para-spinal mass. In seven of ten patients, this bone destruction due to direct extension from metastatic para-aortic tumor was the only recurrent cancer. In contrast, involvement of a long bone, a rib or the skull indicates hematogenous bone metastasis. When a spine X ray or bone scan is positive in the lumbar area in a cervical cancer patient with back pain, a CT scan should be performed to determine the extent of the underlying tumor. This will allow more accurate establishment of a radiation treatment plan, and will improve the chances for successful palliation.