Multidrug resistance in ocular melanoma

AIMS/BACKGROUND

Metastatic disease in patients with ocular melanoma is resistant to chemotherapy. One of the main mechanisms of modulating multidrug resistance is the expression of the multidrug resistance gene 1 (MDR1) product (p-glycoprotein) by tumour cells. The purpose of this study was to evaluate the frequency of expression of the MDR1 gene in ocular melanoma whose primary treatment was surgical excision or enucleation.

METHODS

Twelve recent ocular melanomas were received fresh, snap frozen and cryostat sections of tumour were analysed for expression of MDR1 by immunohistochemistry using a well characterised monoclonal antibody to MDR1. Tumour explants were established in short term tissue culture from four tumours and cell blocks were examined by immunohistochemistry.

RESULTS

MDR1 expression was present in five of 12 ocular melanomas. Upregulation of protein expression was found in four cell lines established in short term culture from tumour explants. A recurrent tumour, initially treated by local excision and radioactive plaque, showed overexpression of MDR1 mRNA.

CONCLUSIONS

These results suggest that significant level of MDR1 may be intrinsically present in ocular melanomas before exposure to drugs involved in multidrug resistance, and indicate the possible importance of MDR1 in modulating chemoresistance in ocular melanoma. Chemosensitisation may be of potential value in planning adjuvant chemotherapy for patients with metastatic disease.

Prostate specific antigen nadir following external beam radiation therapy for clinically localized prostate cancer: the relationship between nadir level and disease-free survival

PURPOSE

We determined whether the prostate specific antigen (PSA) nadir achieved following external beam radiation therapy alone predicts biochemical disease-free survival in a large cohort of men with clinically localized prostate cancer.

MATERIALS AND METHODS

Between January 1986 and October 1993, 364 men with clinically localized, stages T1 to T3 adenocarcinoma of the prostate received definitive external beam radiation therapy with no prior, concomitant or adjuvant endocrine therapy. PSA was measured before treatment in 326 men (90%) and serial PSA was measured following treatment in all patients. All men were followed continuously for at least 24 months (median 44 months, range 24 to 90, mean 46). Biochemical failure after irradiation was defined as PSA of 1.5 ng./ml. or more and 2 consecutive serum PSA elevations.

RESULTS

The 5-year overall biochemical disease-free survival rate for the entire group was 56%. PSA nadir was predictive of subsequent biochemical disease-free survival. The biochemical disease-free survival rate at 3 years was 93, 49 and 16% for PSA nadirs of 0 to 0.99, 1 to 1.99 and 2 or more ng./ml., respectively (p = 0.0001). In a multivariate analysis PSA nadir (0 to 0.99 versus 1.0 to 1.99 versus 2 or more ng./ml.) was an independent predictor of biochemical disease-free survival along with pretreatment PSA, central axis dose, Gleason grade and T stage.

CONCLUSIONS

PSA nadir after radiation therapy is an indicator of subsequent biochemical disease-free survival. Patients who achieve a nadir of less than 1 ng./ml. following external beam radiation therapy have a favorable biochemical disease-free survival rate, while those with a nadir of greater than 1 ng./ml. have a high subsequent failure rate. Strategies to improve results should focus on techniques to increase the likelihood of achieving a PSA nadir of less than 1 ng./ml.

Conformal technique dose escalation for prostate cancer: biochemical evidence of improved cancer control with higher doses in patients with pretreatment prostate-specific antigen > or = 10 NG/ML

PURPOSE

Conformal radiation technology results in fewer late complications and allows testing of the value of higher doses in prostate cancer.

METHODS AND MATERIALS

We report the biochemical freedom from disease (bNED) rates (bNED failure is Prostate Specific Antigen (PSA) > or = 1.5 ng/ml and rising) at 2 and 3 years for 375 consecutive patients treated with conformal technique from 66 to 79 Gy. Median follow-up was 21 months. Biochemical freedom from disease was analyzed for patients treated above and below 71 Gy as well as above and below 73 Gy. Each dose group was subdivided by pretreatment PSA level (< 10, 10-19.9, and > or = 20 ng/ml). Dose was stated to be at the center of the prostate gland.

RESULTS

There was significant improvement in bNED survival for all patients divided by a dose above or below 71 Gy (p = 0.007) and a marginal improvement above or below 73 Gy (p = 0.07). Subdividing by pretreatment PSA level showed no benefit to the PSA < 10 ng/ml group at the higher dose but there was a significant improvement at 71 and 73 Gy for pretreatment PSA 10-19.9 ng/ml (p = 0.03 and 0.05, respectively) and for pretreatment PSA > or = 20 ng/ml (p = 0.003 and 0.02, respectively).

CONCLUSIONS

Increasing dose above 71 or 73 Gy did not result in improved bNED survival for patients with pretreatment PSA < 10 ng/ml at 2 or 3 years. Further dose escalation studies may not be useful in these patients. A significant improvement in bNED survival was noted for patients with pretreatment PSA > or = 10 ng/ml treated above 71 or 73 Gy; further dose escalation studies are warranted.

Erratum to Mutation spectrum of 2-chloroethyl methanesulfonate in Drosophila melanogaster premeiotic germ cells' [Mutation Res. 331 (1995) 213-224]

The 2-chloroethyl methanesulfonate (2CIEMS)-induced alcohol dehydrogenase (Adh) null germline mutation frequency in treated Drosophila melanogaster second instar larval gonia was two orders of magnitude greater than the spontaneous mutation frequency. DNA sequence analysis of 83 Adh null mutations showed that 40 mutations of independent origin were at 23 sites in the Adh gene. The mutation spectrum contained only GC --> AT transitions with 35 mutations (87.5%) at the middle or 3' guanine. In addition, characteristics of glutathione (GSH)-mediated bioactivation were determined for 2CIEMS in vitro. Rates of GSH-mediated conjugation, catalyzed by purified rat liver glutathione-S-transferase (GST), and binding of [35S]GSH-mediated conjugation products to calf thymus DNA were determined for 2CIEMS, 1,2-dichloroethane (EDC) and 1,2-dibromoethane (EDB). The relative rates of GSH-mediated conjugation were the following: 5 mM EDB > 40 mM 2CIEMS > 40 mM EDC. A similar trend was observed for DNA binding of the [35S]GSH-mediated conjugation products when differences in mutagen concentration were considered: EDB > 2CIEMS > EDC. The ratios of DNA binding to GSH conjugation calculated for EDB, EDC and 2CIEMS were 6.8 x 10(-5), 9.3 x 10(-5) and 19.1 x 10(-5), respectively. A narrow range, less than a 3-fold difference, in the ratios of DNA binding to GSH conjugation indicates that the bioactivation of 2CIEMS is mediated by the same mechanism as EDB and EDC. Consequently, 2CIEMS, EDC and EDB may induce a specific mutation in premeiotic germ cells.

Urinary incontinence following external-beam radiotherapy for clinically localized prostate cancer

OBJECTIVES

To determine the incidence of urinary incontinence in men with prostate cancer treated with definitive external-beam radiation therapy and to analyze the impact of various patient and treatment variables on the development of urinary incontinence.

METHODS

The records of all 758 men who received definitive external-beam radiation therapy at our institution between October 1986 and December 1994 were reviewed. The development of incontinence was recorded and graded according to the Late Effects Normal Tissues/Radiation Therapy Oncology Group (LENT/RTOG) scoring system.

RESULTS

Late grade 2 or higher urinary incontinence developed in 4 of 758 patients (0.5%) (3 grade 2; 1 grade 3). The actuarial urinary incontinence rate was 1.3% at 5 years. Patients with a history of prior transurethral resection of the prostate (TURP) had higher rates of urinary incontinence than patients without prior TURP (prior TURP 3 of 132 [2%] versus 1 of 626 [0.2%]; P = 0.02).

CONCLUSIONS

Urinary incontinence following definitive external-beam radiation therapy for clinically localized prostate cancer is a rare event. Previous TURP increases the risk of incontinence, although the risk remains low. There is no evidence that higher doses to the prostate using conformal techniques are associated with an increased risk of urinary incontinence.

Metastatic choroidal melanoma to the contralateral orbit 40 years after enucleation

Metastatic uveal melanoma to the contralateral orbit is extremely rare, with only eight cases in the literature having been reported. We reviewed the clinical presentation, the histologic findings of the primary and secondary tumors, and the clinical outcome of these cases and studied an additional case of metastatic choroidal melanoma to the contralateral orbit that occurred 40 years after enucleation for the primary tumor. The long interval between recognition of the primary tumor and the appearance of clinically manifest metastatic disease in the contralateral orbit is the longest reported in the literature to date. The histologic features of the tumor cells of the enucleation specimen and those of the orbital metastasis were similar, consisting of spindle-cell type with minimal atypia. Combined use of immuno-phenotyping and electron microscopy substantiated the diagnosis of melanoma.

Young patients with prostate cancer have an outcome justifying their treatment with external beam radiation

PURPOSE

The majority of young patients with early stage prostate cancer in the United States are treated with radical prostatectomy. To determine whether this preference for surgical care is justified, we analyzed by patient age the survival without biochemical evidence of disease (bNED) of men with clinically organ-confined prostate cancer treated with external beam irradiation.

METHODS AND MATERIALS

One hundred and sixty-nine men with clinical stages T1-2 adenocarcinoma of the prostate received external beam radiation therapy alone at Fox Chase Cancer Center. All patients had serum prostate-specific antigen (PSA) values less than 10 ng/ml prior to initiation of treatment. Out of 169 patients, 167 had unstaged regional nodes (NX) and all had no evidence for distant metastasis (M0). The median age was 69 years. Criteria for bNED survival were posttreatment serum PSA < or = 1.5 ng/ml and not rising on two consecutive values. The median follow-up is 35 months.

RESULTS

The actuarial 5-year bNED survival of all 169 patients was 85%. The bNED survival of patients less than 65 was not significantly different than that of patients 65 and older (89 vs. 84%, respectively). Patient age, American Joint Committee on Cancer (AJCC) stage, palpation stage, Gleason score, and dose to the center of the prostate were not found to be significant predictors of bNED survival on multivariate analysis.

CONCLUSION

Our results using strict biochemical endpoints are comparable to reported series of similarly staged men treated with prostatectomy. In addition, the patient age of less than 65 is not a prognostic factor for worse outcome after radiation therapy. Young patients with clinically organ-confined prostate cancer who are fully informed of their treatment options can be appropriately accepted for external beam treatment.

Do the results of systematic biopsies predict outcome in patients with T1-T2 prostate cancer treated with radiation therapy alone?

OBJECTIVES

The present study examines whether findings from systematic biopsies add any prognostic information in men with clinical Stage T1-T2 prostate cancer treated with external beam radiation therapy alone.

METHODS

Seventy-two men with clinical T1-T2 prostate cancer had ultrasound-guided quadrant or sextant prostate biopsies prior to treatment with external beam radiotherapy alone between January 1, 1988 and December 31, 1993. The median follow-up is 23 months (range, 11 to 65). Biochemical failure after irradiation was defined as a prostate-specific antigen (PSA) greater than 1.5 ng/mL (Hybritech assay) and rising.

RESULTS

The biochemical relapse-free survival was 90% at 36 months. The percentage of biopsies involved by cancer was not predictive of biochemical relapse-free survival on univariate analysis. Patients with less than 50% positive biopsies had similar biochemical relapse-free survival at 36 months compared to patients with 50% or more positive biopsies (93% versus 89%; P = 0.80). After stratifying according to pretreatment PSA level, the percentage of positive biopsies was not prognostic. A multivariate analysis demonstrated that pretreatment PSA level was the only variable that predicted relapse-free survival (P = 0.01).

CONCLUSIONS

At present, the results of ultrasound-guided quadrant or sextant biopsies do not add further prognostic information, beyond that provided by the pretreatment PSA level, in patients with T1-T2 prostate cancer treated with radiation therapy alone. Further follow-up will be required to confirm these results.

Lateral rectal shielding reduces late rectal morbidity following high dose three-dimensional conformal radiation therapy for clinically localized prostate cancer: further evidence for a significant dose effect

PURPOSE

Using conventional treatment methods for the treatment of clinically localized prostate cancer central axis doses must be limited to 65-70 Gray (Gy) to prevent significant damage to nearby normal tissues. A fundamental hypothesis of three-dimensional conformal radiation therapy (3DCRT) is that, by defining the target organ(s) accurately in three dimensions, it is possible to deliver higher doses to the target without a significant increase in normal tissue complications. This study examines whether this hypothesis holds true and whether a simple modification of treatment technique can reduce the incidence of late rectal morbidity in patients with prostate cancer treated with 3DCRT to minimum planning target volume (PTV) doses of 71-75 Gy.

METHODS AND MATERIALS

The 257 patients with clinically localized prostate cancer who completed 3DCRT by December 31, 1993 and received a minimum PTV dose of 71-75 Gy are included in this report. The median follow-up time was 22 months (range: 4-67 months); 98% of patients had follow-up of longer than 12 months. The calculated dose at the center of the prostate was < 74 Gy in 19 patients, 74-76 Gy in 206 patients, and > 76 Gy in 32 patients. Late rectal morbidity was graded according to the Late Effects Normal Tissue (LENT) scoring system. Eighty-eight consecutive patients were treated with a rectal block added to the lateral fields. In these patients the posterior margin from the prostate to the block edge was reduced from the standard 15 to 5 mm for the final 10 Gy, which reduced the dose to portions of the anterior rectal wall by approximately 4-5 Gy. Estimates of rates for rectal morbidity were determined by Kaplan-Meier actuarial analysis. Differences in morbidity percentages were evaluated by the Pearson chi-square test.

RESULTS

Grade 2-3 rectal morbidity developed in 46 out of 257 patients (18%) and in the majority of cases consisted of rectal bleeding. No patient has developed Grade 4 or 5 rectal morbidity. The actuarial rate of Grade 2-3 morbidity is 23% at 24 months and the median time to the development of Grade 2-3 complications is 15 months. A statistically significant dose effect is evident. The incidence of Grade 2-3 rectal morbidity increased as the dose at the center of the prostate increased (p = 0.05). In patients receiving minimum PTV doses of < or = 76 Gy the use of a rectal block significantly reduced the incidence of Grade 2-3 toxicity; 6 out of 88 (7%) with a block vs. 30 out of 137 (22%) without a block, (p = 0.003).

CONCLUSION

The incidence of late rectal morbidity with 3DCRT to minimum PTV doses of 71-75 Gy is acceptable and to date no Grade 4-5 rectal morbidities have been observed. In our experience, higher doses to the center of the prostate are associated with an increased likelihood of developing Grade 2-3 rectal morbidity but treatment techniques that reduce the total dose to the anterior rectal wall have reduced the incidence of late rectal morbidity. If clinical studies indicate improved tumor control with minimum PTV doses above 71 Gy, then dose escalation above 76 Gy to the center of the prostate should be pursued cautiously with treatment techniques that limit the total dose to the anterior rectal wall.

Patterns-of-failure analysis of patients with high pretreatment prostate-specific antigen levels treated by radiation therapy: the need for improved systemic and locoregional treatment

PURPOSE

The patterns of failure (local and/or regional v metastatic) have been determined for patients with prostate cancer and pretreatment prostate-specific antigen (PSA) levels > or = 20 ng/mL treated with radiation alone with the purpose to design appropriate multimodal treatments.

MATERIALS AND METHODS

One hundred twenty patients with pretreatment PSA levels > or = 20 ng/mL were treated with external-beam radiation alone between February 1988 and October 1993. They were arbitrarily divided by PSA levels, 20 to 29.9 ng/mL, 30 to 49.9 ng/mL, and > or = 50 ng/mL, and analyzed in terms of freedom from any failure (no evidence of biochemical disease [bNED], and PSA level < 1.5 ngm/mL and not increasing), as well as freedom from imaging evidence of distant metastasis (fdm).

RESULTS

There was no significant difference in short-term outcome by pretreatment PSA level, and thus all patients were pooled for analysis. At 4 years, 81% were fdm and 28% were free of any failure. This suggests that approximately 50% have recurred with local and/or regional disease or undetectable metastatic disease. Multivariate analysis indicated that low palpation stage and higher center of prostate dose were associated with better bNED survival. Multivariate analysis indicated that increasing stage and younger age are significantly associated with increasing distant metastasis.

CONCLUSION

Patients with pretreatment PSA levels > or = 20 ng/mL are not optimally treated by irradiation alone. The pattern of failure suggests improvement may come from systemic treatment of metastatic disease and high-dose radiation to improve locoregional disease. To evaluate this, we have begun a multimodal trial of chemohormonal therapy followed by extended-field irradiation.

Prostate carcinoma patients upstaged by imaging and treated with irradiation. An outcome-based analysis

BACKGROUND

The American Joint Committee on Cancer (AJCC) staging of prostate cancer relies upon digital rectal examination (DRE) findings, but suggests using all available information, including prostate imaging studies, prior to definitive treatment of prostate carcinoma. We have studied whether patients upstaged by imaging have a different outcome after treatment with external beam radiation therapy (RT) from those not upstaged.

METHODS

The records of 499 men with clinically localized adenocarcinoma of the prostate treated with only definitive external beam irradiation from January 1986 to December 1993 were reviewed. The 348 patients with any one or a combination of the following pretreatment imaging studies were considered eligible; transrectal ultrasound (TRUS), pelvic MRI, or endorectal MRI. Patients were assigned two clinical stages: one based upon palpation criteria alone (palpation stage) and the other allowing for any upstaging by imaging abnormalities (AJCC or imaging stage). The Kaplan-Meier method was used to estimate biochemical no evidence of disease (bNED) survival where a failure was defined as a prostate specific antigen (PSA) greater than 1.5 and increasing. Differences in outcome were evaluated by the log-rank test.

RESULTS

Overall upstaging by TRUS or MRI to any higher stage occurred in 115 of 312 palpation T1c-T2c patients (37%). These upstaged patients had an unexpected improvement in bNED survival (84% vs. 71%, P = 0.05) compared with those who were not upstaged due to the upstaged patients having a significantly greater number with a pretreatment PSA < 10 ng/mL. T1c patients were upstaged by imaging in 81% of the 94 patients. The 36-month bNED survival of palpation T1c and imaging T2 patients was similar (88% vs. 88%, P = NS), but both were significantly improved compared with the 36-month bNED survival for palpation T2 patients (88% vs. 71%, P = 0.04). There was no significant difference in 36-month bNED survival for imaging T2c (bilobar disease) patients compared with their original palpation stage disease. Upstaging to T3 occurred in 10% of palpation T1c-T2c patients. There was no difference in 36-month bNED survival for the imaging T3 patients compared with their original palpation stage (84% vs. 71%, respectively, P = 0.04). There was a significant improvement in the 36-month bNED survival for imaging T3 patients compared with palpation T3 patients (84% vs. 50% respectively, P = 0.01). Multivariate analysis demonstrated palpation stage to be a significant predictor of bNED survival (P = 0.001), while AJCC stage (including imaging) is not predictive.

CONCLUSIONS

Using the endpoint of bNED survival, upstaging by TRUS/MRI does not separate prostate cancer patients treated with RT into groups with different prognoses. Upon multivariate analysis, palpation stage alone, not AJCC stage including imaging upstaging, is a significant predictor of bNED survival.

Ocular tumoral calcinosis. A clinicopathologic study

Tumoral calcinosis is a rare systemic disorder characterized by para-articular ectopic soft-tissue calcification. This case report describes the ophthalmic features (palpebral conjunctival calcific nodules, the white limbal girdle of Vogt, disc drusen, and angioid streaks) in a 38-year-old Asian woman who had tumoral calcinosis associated with hyperphosphatemia. A morphologic study of the calcified nodules on the palpebral conjunctiva disclosed deposition of hydroxyapatite crystals in an extracellular matrix (deposit) containing alcianophilic mucopolysaccharides. Excision of the eyelid nodules was not followed by recurrence.

Do overall treatment time, field size, and treatment energy influence local control of T1-T2 squamous cell carcinomas of the glottic larynx?

PURPOSE

To evaluate treatment and patient related prognostic factors that may influence local control in the treatment of T1-T2 squamous cell carcinoma of the glottic larynx.

METHODS AND MATERIALS

One hundred nine patients with invasive, previously untreated T1-T2 squamous cell carcinoma of the glottic larynx were treated with curative intent with radiotherapy at the Fox Chase Cancer Center between June 1980 and November 1991. Follow-up ranged from 26-165 months (mean 83 months).

RESULTS

The 2-year local control rates for patients with T1 and T2 lesions were 89% and 80%, respectively. The 2-year local control rate for patients whose overall treatment time was < 50 days was 92% vs. 82% for patients whose overall treatment time was > 50 days (p = 0.07). The 2-year local control rate for patients treated with an irradiated area < 36 cm(2) was 90% compared to 86% in patients who were treated to an area > or = 36 cm(2). The 2-year local control rate for patients treated with 60Co was 83% vs. 92% for patients treated with 6 MV x-ray. Cox proportional hazards regression analysis was performed using the following variables: treatment energy, irradiated area, gender, tobacco pack years, tumor differentiation, overall treatment time, total dose, dose per fraction, and T stage. Overall treatment time (p = 0.05) was the only variable that significantly influenced local control.

CONCLUSION

Extending the overall treatment time was found to adversely influence local control. Neither the irradiated area nor treatment energy was found to influence local control in early stage vocal cord carcinoma.

Amebic keratitis in a wearer of disposable contact lenses due to a mixed Vahlkampfia and Hartmannella infection

PURPOSE

To support the hypothesis that Acanthamoeba is not a unique cause of amebic keratitis, we report a case of amebic keratitis in which viable Acanthamoeba could not be isolated from corneal tissue. Vahlkampfia and Hartmannella, two other genera of free-living ameba, were isolated, however, using prolonged culture.

METHODS

A 24-year-old wearer of soft contact lenses had keratitis. Extensive histologic and microbiologic investigations were performed on corneal scrape, biopsy, and keratoplasty tissue. Contact lenses, storage case, and the home water supply, where contact lens hygiene was practiced, were examined for the presence of micro-organisms.

RESULTS

No viruses, pathogenic bacteria, or fungi were detected from corneal tissue samples. Amebae were observed using light and electron microscopy, but these could not be unequivocally classified using immunocytochemical staining. Viable Vahlkampfia and Hartmannella, but no Acanthamoeba, were isolated from the corneal biopsy sample. Indirect immunofluorescence with a range of polyclonal rabbit antisera raised against axenically cultivated stains of the three amebal genera was unhelpful because of cross-reactivity. A diverse range of micro-organisms was present within the storage case, including the three amebal species. Amebic cysts also were associated with the contact lens.

CONCLUSION

A mixed non-Acanthamoeba amebic keratitis has been identified in a wearer of soft contact lenses where lack of storage case hygiene provided the opportunity for the free-living protozoa Vahlkampfia and Hartmannella to be introduced to the ocular surface. When Acanthamoeba-like keratitis occurs, but where Acanthamoeba cannot be isolated using conventional laboratory culture methods, alternate means should be used to identify other amebae that may be present. Polyclonal immunofluorescent antibody staining was unreliable for generic identification of pathogenic free-living amebae in corneal tissue.

Systematic biopsies: do they add prognostic information in men with clinically localized prostate cancer treated with radiation therapy alone?

PURPOSE

To determine whether systematic biopsy can help predict treatment outcome in men with clinically localized prostate cancer treated with external-beam radiation therapy alone.

MATERIALS AND METHODS

Two hundred twenty-four men with clinically localized prostate cancer underwent ultrasound-guided systematic biopsies before undergoing external-beam radiation therapy. Median follow-up was 25 (range, 4-80) months. Treatment failure after irradiation was defined as a prostate-specific antigen (PSA) level greater than 1.5 ng/mL and rising.

RESULTS

Univariate analysis demonstrated that the percentage of biopsy specimens involved by cancer was predictive of relapse-free survival. Patients in whom more than 50% of biopsy specimens were positive had significantly lower relapse-free survival rates at 36 months than patients with 50% or fewer positive biopsy specimens. After stratifying patients according to pretreatment PSA level, however, the percentage of positive biopsy specimens was no longer prognostic. Multivariate analysis demonstrated that pretreatment PSA level was the only variable that enabled prediction of relapse-free survival.

CONCLUSION

Systematic biopsy added little further prognostic information beyond that provided by pretreatment PSA level. A larger series with longer follow-up is necessary to verify these results.

Pretreatment prostate-specific antigen doubling times: clinical utility of this predictor of prostate cancer behavior

PURPOSE

The distribution of pretreatment and posttreatment prostate specific antigen (PSA) doubling times (PSADT) varies widely. This report examines the pretreatment PSADT as an independent predictor of biochemical freedom from disease (bNED) and describes the clinical utility of PSADT.

METHODS AND MATERIALS

Ninety-nine patients with T1-3 NX, M-0 prostate cancer treated between February 1989 and November 1993 have pretreatment PSADTs calculated from three or more PSA levels. Biochemical disease-free (bNED) survival (failure is PSA > or = 1.5 ngm/ml and rising) is evaluated by multivariate analysis of common prognostic indicators and PSADT.

RESULTS

Prostate-specific antigen doubling time (PSADT) is a significant predictor of survival along with radiation dose. Patients with a pretreatment PSADT of < 12 months show 50% failure by 18 months, while those with a PSADT that is not increasing show only 3% failure at 3 years.

CONCLUSIONS

Prostate-specific antigen doubling time (PSADT) is a predictor of bNED outcome in prostate cancer. Patients with PSADT < 12 months have aggressive disease, and should be considered for multimodal therapy. Slow PSADT (> or = 5 years) is observed in 57% of patients, and this end point may be considered in the decision to observe rather than to treat. After treatment failure, the PSADT may be used to determine which patients do not need immediate androgen deprivation.

Oropharyngeal carcinoma treated with radiotherapy: a 30-year experience

PURPOSE

This study was done to determine the outcome in patients with oropharyngeal carcinoma treated at the University of Florida with radiotherapy alone to the primary site, for comparison with reported results of other types of treatment.

METHODS AND MATERIALS

Of a consecutive cohort of 785 patients with biopsy-proven, previously untreated, invasive squamous cell carcinoma of the oropharynx, this report is based on the 490 patients who had continuous-course irradiation with curative intent at the University of Florida between October 1964 and January 1991. All patients had a minimum 2-year follow-up. Forty-eight percent had Stage T3 or T4 disease, and 64% had clinically apparent neck node metastases. The median radiation dose was 68 Gy for once-a-day treatment and 76.8 Gy for twice-a-day treatment. Patients with advanced neck node disease had planned neck dissection(s) after radiotherapy.

RESULTS

The overall local control rate after radiotherapy alone was 73%. The ultimate local control rate (including surgical salvage) was 78%. At 5 years, the probability of control of neck disease was 85%; control above the clavicles, 67%; absolute survival, 44%; cause-specific survival, 77%; distant metastasis (as the first or only site of failure), 11%. Thirteen patients (2.6%) experienced severe treatment complications.

CONCLUSION

Radiotherapy results in tumor control and survival rates comparable with rates achieved with combined irradiation and surgery, with less morbidity.

20th annual Frank Costenbader Lecture--adult strabismus

BACKGROUND

A retrospective analysis of adults with strabismus was done to examine the potential risks and the possible benefits of surgical treatment and to describe the types of adult strabismus.

METHODS

Eight hundred ninety-two patients were analyzed. Age at time of surgery ranged from 9 years to 89 years. The average follow up was 34 months. Major types of strabismus were grouped by their original diagnoses. The group of patients with horizontal strabismus, which usually had an onset before 9, was termed the before visual maturity (BVM) group. The group of patients with paretic or restrictive strabismus usually had the onset of strabismus after age 9 and was termed the after visual maturity (AVM) group.

RESULTS

Patients with adult strabismus can gain restoration of alignment, as well as binocular function. At the last postoperative visit, 74% of the BVM group were aligned within 15 prism diopters. Not only was restoration of alignment accomplished, many of them gained some degree of sensory fusion as measured by the Worth 4-Dot (W4D) or Titmus stereoacuity. Twenty-nine percent of patients with congenital esotropia had some sensory fusion. The other subtypes in the BVM group had even higher percentages of patients with postoperative stereoacuity. In the AVM group, 92% had fusion at the last postoperative visit.

CONCLUSIONS

The outcomes of adult strabismics in our study show that certain benefits can be gained from correction of ocular alignment. Restoration of alignment, elimination of diplopia and sensory fusion are functional benefits that can be obtained through strabismus surgery in the adult patient. It is clear that adult strabismus is more than just a cosmetic problem and treatment is worthwhile.

Abnormal extracellular material in the levator palpebrae superioris complex in congenital ptosis

OBJECTIVE

To determine the pathologic abnormalities of the levator palpebrae superioris in congenital ptosis.

METHODS

By means of light and electron microscopy and immunohistochemistry, anterior levator tissue specimen from 15 patients with congenital ptosis excised during routine levator resections were examined.

RESULTS

All specimens showed lack of muscle fibers with endomysial and perimysial fibrosis and thickening of the aponeurosis. In addition, in four of the 15 patients, an abnormal extracellular material was present. By light microscopy this appeared as an unusual amorphous material arranged in clumps and bands, and electron microscopy showed it to consist of parallel coarse bundles of fibrillogranular material. Collagen type III and fibronectin were identified within this material by immunohistochemistry. There was no detectable collagen types I, II, IV, V, VI, or VII or laminin, and the material did not stain for actin, myosin, myoglobin, amyloid P component, or amyloid A.

CONCLUSIONS

In four of 15 samples of levator palpebrae superioris from patients with congenital ptosis, we identified an unusual amorphous extracellular material that stained positively for collagen type III and fibronectin on immunohistochemistry. This novel material, which we call "amorphocollagenoid," may represent a product of dysgenesis of the levator tissues. The source and full composition of this material merit further study.

Mutation spectrum of 2-chloroethyl methanesulfonate in Drosophila melanogaster premeiotic germ cells

The 2-chloroethyl methanesulfonate (2ClEMS)-induced alcohol dehydrogenase (Adh) null germline mutation frequency in treated Drosophila melanogaster second instar larval gonia was two orders of magnitude greater than the spontaneous mutation frequency. DNA sequence analysis of 83 Adh null mutations showed that 40 mutations of independent origin were at 23 sites in the Adh gene. The mutation spectrum contained only GC-->AT transitions with 35 mutations (87.5%) at the middle or 3' guanine. In addition, characteristics of glutathione (GSH)-mediated bioactivation were determined for 2ClEMS in vitro. Rates of GSH-mediated conjugation, catalyzed by purified rat liver glutathione-S-transferase (GST), and binding of [35S]GSH-mediated conjugation products to calf thymus DNA were determined for 2ClEMS, 1,2-dichloroethane (EDC) and 1,2-dibromoethane (EDB). The relative rates of GSH-mediated conjugation were the following: 5 mM EDB > 40 mM 2ClEMS > 40 mM EDC. A similar trend was observed for DNA binding of the [35S]GSH-mediated conjugation products when differences in mutagen concentration were considered: EDB > 2ClEMS > EDC. The ratios of DNA binding to GSH conjugation calculated for EDB, EDC and 2ClEMS were 6.8 x 10(-5), 9.3 x 10(-5) and 19.1 x 10(-5), respectively. A narrow range, less than a 3-fold difference, in the ratios of DNA binding to GSH conjugation indicates that the bioactivation of 2ClEMS is mediated by the same mechanism as EDB and EDC. Consequently, 2ClEMS, EDC and EDB may induce a specific mutation in premeiotic germ cells.

Clinical and biochemical evidence of control of prostate cancer at 5 years after external beam radiation

PURPOSE

We demonstrate the 5-year survival rate for patients with prostate cancer treated by irradiation, the value of the conformal technique and prostate specific antigen (PSA) doubling times after irradiation.

MATERIALS AND METHODS

The outcome of 502 consecutive patients with stages T1 to T3 prostate cancer treated by irradiation alone is reported. PSA doubling times before and after failure are reported for 13 patients and posttreatment PSA doubling times are reported for 93 consecutive patients in whom radiation failed.

RESULTS

The actuarial survival with biochemical freedom from disease (PSA nadir 1.5 or less not increasing) at 5 years was 44% for all patients, 50% for the conformal treatment group and 39% for the conventional therapy group. PSA doubling times after radiation failure were variable, with 42% greater than 12 months.

CONCLUSIONS

The 5-year survival rate for patients with prostate cancer treated by irradiation is excellent. The conformal technique is superior to conventional therapy and there is no evidence that irradiation accelerates the growth rate of prostate cancer.