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Biomedical subjects

J A Shields

Publications and source records attributed to J A Shields.

At least 181 records · Page 10Linked to original sources
PubMed1997

Chewing-induced visual impairment from a dumbbell dermoid cyst.

A 29-year-old woman presented with a 1-year history of blurred vision in her left eye while chewing. Examination revealed a rubbery mass with ill-defined borders in the superotemporal brow region. Imaging studies demonstrated a cystic lesion extending from the temporal fossa into the orbit through a bony defect in the lateral orbital wall, assuming a dumbbell configuration. Histopathology of the excised specimen confirmed the clinical diagnosis of a dermoid cyst of cutaneous origin. We believe that the patient's visual disturbance was caused by transient displacement of orbital contents by the dermoid cyst as it was compressed into the orbit during mastication. Dermoid cysts are frequently associated with bony defects, which may require preoperative imaging and may produce unexpected symptoms.

Adult↗
PubMed1997

Functional vision is improved in the majority of patients treated with external-beam radiotherapy for choroid metastases: a multivariate analysis of 188 patients.

PURPOSE: Metastatic deposits are the most common intraocular malignancies. We evaluated the efficacy of external-beam radiotherapy (EBRT) in the palliation of posterior uveal metastases in terms of clinically relevant outcomes: functional vision, tumor control, and globe preservation. PATIENTS AND METHODS: Four hundred eighty-three consecutive patients (578 eyes) were diagnosed with intraocular metastatic disease from solid tumors between 1972 and 1995. Of these, 233 eyes (188 patients) had lesions of the posterior uveal tract and received EBRT. Best-corrected visual acuity (VA) was documented pre- and post-EBRT. Visual function was considered excellent if VA < or = 20/50, navigational if 20/60 to 20/200, and legally blind if > or = 20/400. Most patients received 30 to 40 Gy in 2- to 3-Gy fractions to the posterior or entire globe. RESULTS: Fifty-seven percent of all assessable eyes had improved visual function or maintained at least navigational vision following EBRT. Thirty-six percent of legally blind eyes regained useful vision. Ninety-three percent experienced no clinical evidence of tumor progression and the globe preservation rate was 98%. The following characteristics independently predicted improvement to or maintenance of excellent vision on multivariate analysis: excellent vision pre-EBRT (P = .001), age less than 55 years (P = .004), white race (v black/Hispanic) (P = .003), and tumor base diameter less than 15 mm (P < .001). CONCLUSION: EBRT effectively restores and maintains useful vision in patients with choroid metastases, with a globe preservation rate of 98%. Patients less than 55 years with pretreatment VA better than 20/60 and tumor diameter less than 15 mm are most likely to benefit from this therapeutic intervention.

Adult↗
PubMed1997

Time to systemic metastases in patients with posterior uveal melanoma.

A total of 116 patients, all of whom had systemic metastases from posterior uveal melanoma, were evaluated to identify potential indicators for time to systemic metastasis. In the multivariate Cox proportional hazards model with clinically available variables, the age at initial treatment for uveal melanoma, gender and diameter of the primary tumor were revealed to be independent predictive factors for time to systemic metastasis. Age older than 60 years, male gender, and diameter of the primary uveal melanoma more than 10 mm were proved to be independent unfavorable factors. The estimated median time to systemic metastasis for the most unfavorable group (age > 60, male, diameter > 10 mm) was 20.2 months in contrast with 76.1 months for the most favorable group (age < or = 60, female, diameter < or = 10 mm). Although the results of this study cannot be applied to all patients with posterior uveal melanoma, predictive factors for time to systemic metastasis in those patients who have recurred supplement the information obtained from prognostic factors for the likelihood of metastasis or survival. They contribute not only to our understanding of the biology of metastasizing posterior uveal melanoma, but also in developing appropriate strategies for follow-up and treatment.

Analysis of Variance↗
PubMed1997

Iris juvenile xanthogranuloma studied by immunohistochemistry and flow cytometry.

An unusual large tan iris mass in a 19-month-old child was removed by iridocyclectomy and studied by light microscopy, immunohistochemistry, and flow cytometry. The excised mass consisted of granulomatous inflammation with numerous osteoclast-like giant cells and scattered atypical Touton giant cells. Immunohistochemistry studies showed that the cells were most consistent with mononuclear histiocytes. Flow cytometry showed that 90% of the cells sampled were T-lymphocytes, with a predominance of T-suppresser cytotoxic cells. Juvenile xanthogranuloma (XG) of the iris can occur as a large solitary mass, without signs of intraocular inflammation or hyphema.

Biomarkers↗
PubMed1997

Orbital dermoid cysts: clinicopathologic correlations, classification, and management. The 1997 Josephine E. Schueler Lecture.

The dermoid cyst is one of the most common space-occupying orbital lesions, but there has been no large series that details the clinical, pathologic, and therapeutic aspects of this condition. Furthermore, despite the various presentations and types of dermoid cysts, there is no clinically applicable classification of these lesions. We performed a retrospective histopathologic study of 197 consecutive orbital and periorbital dermoid cysts excised at Wills Eye Hospital during a 32-year period, correlated the histopathologic findings with the recorded clinical and radiographic observations, and devised a clinically applicable classification of orbital dermoid cysts. The mean age at excision was 17 years (range, 5 months to 85 years), and the most frequent clinical finding was a painless subcutaneous mass, present in 89% of cases. In 72% of patients, the mass was located in the superotemporal orbital region and produced no abnormalities of vision or intraocular pressure. Computed tomography and magnetic resonance imaging, performed mainly in the more recent cases, disclosed a characteristic round to ovoid cystic lesion with a well-defined lining. Histopathologically, 165 of the cysts (84%) were lined by keratinizing, stratified squamous epithelium. Ten (5%) were lined by nonkeratinizing epithelium resembling conjunctival epithelium. Hair shafts were present in the wall or lumen of the cyst in 195 (99%) of specimens, sebaceous glands in 148 (75%), and sweat glands in 39 (20%); inflammation was present in 75 cases (38%). Based on these personal observations and a review of the literature, a classification of orbital dermoid cysts is proposed that we believe will provide guidance for the ophthalmologist in the management of these lesions.

Adolescent↗
PubMed1996

External beam radiation for retinoblastoma: results, patterns of failure, and a proposal for treatment guidelines.

PURPOSE: To analyze treatment results and patterns of failure following external beam radiation for retinoblastoma and propose treatment guidelines according to specific clinical variables. METHODS AND MATERIALS: We analyzed 27 patients (34 eyes) with retinoblastoma who received external beam radiation as initial treatment at Hahnemann University Hospital from October 1980 to December 1991 and have been followed for at least 1 year. Of the 34 eyes, 14 were Groups I-II (Reese-Ellsworth classification), 7 were Group III, and 13 were Groups IV-V. Doses ranged from 34.5-49.5 Gy (mean 44.3 Gy, median 45 Gy) in 1.5-2.0 Gy fractions generally delivered through anterior and lateral wedged pair fields. RESULTS: At a mean follow up of 35.2 months (range 12-93 months), local tumor control was obtained in 44% (15 out of 34) of eyes with external beam radiation alone. Salvage therapy (plaque brachytherapy, cryotherapy, and/or photocoagulation) controlled an additional 10 eyes (29.5%), so that overall ocular survival has been 73.5%. Local tumor control with external beam radiotherapy alone was obtained in 78.5% (11 out of 14) of eyes in Groups I-II, but in only 20% (4 out of 20) of eyes in Groups III-V. A total of 67 existing tumors were identified prior to treatment in the 34 treated eyes and local control with external beam radiation alone was obtained in 87% (46 out of 53) of tumors measuring 15 mm or less and in 50% (7 out of 14) of tumors measuring more than 15 mm. When analyzing patterns of failure in the 19 eyes that relapsed, a total of 28 failure sites were identified and consisted of progression of vitreous seeds in seven instances (25% of failure sites) recurrences from previously existing tumors in 10 instances (36% of failure sites) and development of new tumors in previously uninvolved retina in 11 instances (39% of failure sites). CONCLUSIONS: 1) We find that external beam radiation to a dose of 45 Gy in fractions of 1.5 to 2.0 Gy provides adequate tumor control in retinoblastoma eyes Groups I-II (Reese-Ellsworth classification) or tumors measuring 15 mm in diameter or less. Eyes in more advanced group staging or containing tumors larger than the 15 mm seem to require higher radiation doses. We propose treatment guidelines for external beam radiation of retinoblastoma that specifically take into account the important clinical variables of tumor stage and patient age. 2) External beam radiation does not prevent the appearance of new tumors in clinically uninvolved retina. Therefore, the traditional belief that external beam radiation can treat the retina "prophylactically" should be seriously questioned. Due to this finding and their significant less morbidity, focal treatment modalities (plaque brachytherapy, photocoagulation, and/or cryotherapy), when clinically feasible, should be considered the treatment of choice for intraocular retinoblastoma. External beam radiation should be considered only when focal treatment modalities are not clinically indicated.

Dose-Response Relationship, Radiation↗
PubMed1996

Deletion mapping of chromosome region 9p21-p22 surrounding the CDKN2 locus in melanoma.

The cyclin-dependent kinase-4 inhibitor gene CDKN2, localized at chromosome region 9p21, has been shown to be a familial melanoma gene, though we found that mutations of it are rare in uncultured sporadic melanomas. To determine Whether the region of allelic loss at 9p21 frequently observed in sporadic melanomas includes the CDKN2 locus, new polymorphic microsatellite probes were isolated from the genomic segments surrounding the CDKN2 gene and used for the study of loss of heterozygosity (LOH) in melanoma. The LOH study of matched uncultured tumor-constitutional DNA pairs from 66 metastatic cutaneous and 19 primary uveal melanomas showed that 63% and 32% of the respective tumors suffered allelic loss in the 9p21 region. Two regions of common losses which did not include the CDKN2 locus were observed: in a region of common loss near the D9S157 locus, telomeric to the CDKN2 locus, deletions were observed in 51% of informative cases; in the other region of common loss, near the D9S171 locus, centromeric to the CDKN2 locus, deletions were observed in 47% of informative cases. At the D9S974 locus, located within 20 kb of the CDKN2 gene, deletions were observed in 43% of informative cases. Homozygous deletions of the CDKN2 locus were observed in 8 cases of cutaneous melanoma and 2 cases of uveal melanoma; mutations in CDKN2 exon 2 were found in 2 of the 46 cases with allelic deletion in 9p21. Our results support the following conclusions: (i) somatic mutation of the CDKN2 gene is rare in sporadic melanomas with allelic loss at 9p21; (ii) homozygous loss is more frequent than mutation of the CDKN2 gene in sporadic melanomas; (iii) at 9p21-p23 genes other than CDKN2 may be involved in the development of sporadic melanomas.

Alleles↗
PubMed1996

Familial uveal melanoma. Clinical observations on 56 patients.

OBJECTIVE: To study the clinical profile and kindreds of patients with familial uveal melanoma (FUM). DESIGN: Retrospective case series. SETTING: Tertiary referral center. PATIENTS: Medical charts of 4500 patients with uveal melanoma were reviewed for family history of uveal melanoma. The clinical profile of these patients and their kindreds were studied to determine the incidence of FUM and pattern of inheritance. The association of FUM to cutaneous melanoma, familial atypical mole and melanoma syndrome, and other nonmelanocytic cancers was analyzed using statistical methods. RESULTS: Of 4500 patients with uveal melanoma, 56 patients in 27 families (0.6%) had a family history of uveal melanoma. The uveal melanoma in all 56 familial patients was unilateral. In 17 cases (63%), the second affected relative was a first-degree relative. In the remainder, the second affected relative was a second- (22%) and third-degree (15%) relative. In 25 families (93%) only two members were affected, and in two families (7%) three members had uveal melanoma. Patients with FUM were four times as likely to have a second primary malignant neoplasm than were people in the general population. However, no evidence was seem that unaffected kindreds of patients with FUM were at higher risk of having a second primary malignant neoplasm. CONCLUSIONS: Familial involvement in uveal melanoma is rare. Familial uveal melanoma most often (63%) affects first-degree relatives, rarely affects more than two persons in a family, and may be associated with a generalized inherited predisposition to cancer. Further genetic studies are necessary to fully characterize FUM syndrome.

Adult↗
PubMed1996

Malignant melanoma of the optic nerve.

A 67-year-old man was diagnosed as having a melanocytoma of the optic disc in the left eye. Observation during a 5-year period showed no change in the lesion. At age 72 years, he had abrupt visual loss to no light perception in the affected left eye. Clinical examination disclosed little enlargement of the papillary tumor but ultrasonographic evidence of optic nerve infiltration. Precontrast magnetic resonance imaging studies disclosed a hyperintense infiltrative lesion in the enlarged left optic nerve. Enhancement features of the lesion excluded a hemorrhagic process. The eye was removed with a 22.5-mm segment of optic nerve. Histopathologic examination showed a large, necrotic, mixed-cell malignant melanoma confined to the optic nerve. No choroidal involvement or viable melanocytoma cells were documented. This case stresses that it may be difficult to differentiate a melanocytoma from a primary malignant melanoma of the optic nerve.

Aged↗
PubMed1996

Diffuse choroidal melanoma. Clinical features predictive of metastasis.

OBJECTIVE: To assess the clinical features that predict metastasis of diffuse choroidal melanoma. DESIGN: A review of patients who had been diagnosed clinically as having diffuse choroidal melanoma evaluated on the Oncology Service at Wills Eye Hospital, Philadelphia, Pa. MAIN OUTCOME MEASURE: Effect on metastasis of clinical features of the tumor. RESULTS: Of 3500 consecutive patients with choroidal melanoma, 111 (3%) had diffuse choroidal melanoma. Of these 111 tumors, the mean tumor base was 14.7 mm and the mean overall tumor thickness was 2.1 mm. The thickness-to-base percentage averaged 14.8%. The tumor had poorly defined margins in 39 patients (35%), orange pigment on its surface in 49 (44%), and a secondary serous retinal detachment in 76 (68%). Optic nerve invasion was clinically suspected in 2 patients (2%) and transcleral extension in 3 (3%). Initial management was enucleation in 36 patients (32%), plaque radiotherapy in 60 (54%), laser photocoagulation in 3 (3%), and observation in 12 (11%). During a mean follow-up of 5.3 years (median, 3.9 years), metastasis developed in 29 patients (26%). Using Kaplan-Meier survival estimates, the probability of metastasis developing was 16% at 3 years, 24% at 5 years, and 36% at 10 years. The clinical factors predictive of metastasis by univariate analysis included tumor basal dimension 18 mm or more (P = .002), poorly defined tumor margins (P = .03), transcleral extension (P = .003), and optic nerve invasion (P = .03). The clinical factors predictive of metastasis by multivariate analysis included basal dimension of 18 mm or more (P = .01), optic nerve invasion (P = .03), and poorly defined tumor margins (P = .05). CONCLUSIONS: Despite its relative flatness, diffuse choroidal melanoma carries a metastatic potential of 24% at 5 years. The risks for metastasis are greatest with increasing tumor base and poorly defined margins. Recognition of the clinical features of this tumor in the earliest stage and prompt treatment are encouraged.

Adolescent↗
PubMed1996

Familial uveal melanoma, III. Is the occurrence of familial uveal melanoma coincidental?.

OBJECTIVE: To ascertain whether the familial occurrence of uveal melanoma was coincidental in kindreds in which 1 first-degree relative of the proband had also been affected with primary uveal melanoma. PATIENTS: In a series of 4500 patients with primary uveal melanoma, 17 kindreds were identified in which a first-degree relative of the proband had also been affected with primary uveal melanoma. DESIGN: In the 17 families in which a first-degree relative of the proband had been affected, primary uveal melanoma was classified as familial. In the remaining 4483 families, primary uveal melanoma was classified as sporadic. The expected number of affected first-degree relatives of probands for a family was estimated, assuming an incidence rate of 6 cases per million population per year in each type of family. RESULTS: The expected number of affected first-degree relatives was calculated to be 0.81, with an SE of 0.08, compared with 17 observed affected first-degree relatives (P < .001). CONCLUSION: Our study provides strong statistical evidence that occurrence of familial uveal melanoma is not coincidental.

Adolescent↗
PubMed1996

Chemoreduction in the initial management of intraocular retinoblastoma.

BACKGROUND: Chemoreduction is a method of reducing tumor volume to allow for more focused, less damaging therapeutic measures. OBJECTIVE: To determine whether chemoreduction could be used to decrease the size of retinoblastoma so that enucleation or external beam radiotherapy could be avoided and more conservative modalities employed. METHODS: A prospective pilot study was performed to assess the effectiveness of a 2-month chemoreduction regimen of vincristine sulfate, etoposide, and carboplatin in patients with retinoblastoma. The study included 20 patients with 54 tumors in 31 eyes. RESULTS: At the initial examination, the mean tumor base was 12 mm and the thickness, 7 mm. Vitreous seeds were present in 14 eyes (45%). A secondary retinal detachment was present in 24 eyes (77%) and, when present, involved a mean of 71% of the retina. In 11 eyes (36%) the retina was totally detached with serous subretinal fluid. After 2 months of chemoreduction, all 54 tumors showed regression in size, and 48 (89%) showed evidence of calcification. The mean tumor base was 8 mm and the thickness, 4 mm. Overall, there was a mean 35% decrease in base and 49% decrease in thickness of the tumor at the end of the treatment period. A complete response was found in 25 tumors (46%) and a partial response in 29 (54%). The subretinal fluid had resolved completely in 50% of the cases (12/24 eyes), and, in the 11 eyes with total retinal detachment, the subretinal fluid had completely resolved, leaving flat retina, in 6 eyes (54%). The vitreous seeds demonstrated some degree of regression in all cases, and in 5 eyes there was 90% to 100% calcification of the seeds. Short-term systemic toxic effects were mild (transient bone marrow suppression). Enucleation was avoided in all cases; external beam radiotherapy was necessary in 9 eyes because of diffuse vitreous seeds. The remaining 22 eyes were treated with local methods after chemoreduction. CONCLUSION: Tumor shrinkage with chemoreduction may allow treatment with less invasive measures, such as cryotherapy, laser photocoagulation, thermotherapy, or plaque radiotherapy, thereby avoiding enucleation and external beam radiotherapy.

Antineoplastic Agents, Phytogenic↗
PubMed1996

Plaque radiotherapy for juxtapapillary choroidal melanoma. Visual acuity and survival outcome.

OBJECTIVES: To assess the effect of plaque radiotherapy on the visual acuity of patients with juxtapapillary choroidal melanoma and to determine the clinical predictive factors for radiation retinopathy, radiation papillopathy, local tumor recurrence, and distant metastasis. DESIGN: A retrospective review of the medical records of 93 patients with juxtapapillary choroidal melanoma who were treated initially with plaque radiotherapy. RESULTS: During a mean follow-up of 78 months, radiation retinopathy developed in 81 patients (87%) and radiation papillopathy developed in 48 patients (52%) after a mean interval of 21 and 27 months, respectively. The univariate variables that were significant predictors of radiation retinopathy were history of diabetes mellitus (P = .05) and use of a notched radioactive plaque (P = .04). The factors predictive of radiation papillopathy were age (> 45 years; P = .01), history of diabetes mellitus (P = .05), mushroom-shaped tumor configuration (P = .006), and nasal location of the tumor (P = .04). By using Kaplan-Meier survival curves, we found that the proportion of the 93 patients with radiation retinopathy was 87 (94%) at 5 years and with radiation papillopathy was 53 (57%) at 5 years. By using life-table analysis, we found that the proportion of the 93 patients who experienced a decrement of at least 3 lines of visual acuity was 67 (72%) by 50 to 60 months. Local tumor recurrence was documented in 14 patients (15%) after a mean interval of 41 months. The age of the patient (< 35 years; P = .02) and the superior (P = .004) and inferior (P = .05) locations of the tumor were predictive of local tumor recurrence. Distant metastasis developed in 11 patients (12%) after a mean interval of 44 months. The factors predictive of distant metastasis were a tumor with a basal diameter larger than 6.0 mm (P = .05), the superior location of the tumor (P = .01), and local tumor recurrence (P < .001). CONCLUSION: Based on these observations, plaque radiotherapy remains a potential option vs enucleation for the management of juxtapapillary choroidal melanoma.

Brachytherapy↗