Impact of lymph node yield at prostatectomy on outcomes in NRG/RTOG 9601

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Background: A recent study ( Fossati et al, 2018) found that higher lymph node count at radical prostatectomy was associated with improved outcomes in patients treated with salvage radiation for elevated prostate-specific antigen (PSA) after surgery. We sought to validate these results in NRG/RTOG 9601, a randomized controlled trial of men with pT2/T3 disease who underwent either radiation (RT) alone or RT+antiandrogen (bicalutamide) therapy for PSA elevation following radical prostatectomy from 1998-2003. Methods: We reviewed available pathology reports for all patients in NRG/RTOG 9601 to determine the nodal count at radical prostatectomy. Clinical data was as of 11/5/2015, same as the primary endpoint for the trial. Cox proportional hazards models were used to assess the effect of number of positive lymph nodes, treatment arm (RT alone or RT+bicalutamide), Gleason score, positive margins, and seminal vesicle invasion on the following endpoints: times to local and distant failure and overall and disease specific survival. Results: Out of the 760 patients originally eligible in the trial, 552 (73%, 276 in each arm) had complete data available. Median node count in the entire cohort was 6 (range 0-33, Q1-Q3 3-9). There were no significant differences between treatment arms in terms of patient demographic or clinical characteristics, including total lymph nodes removed in either arm (RT alone vs RT+bicalutamide median 5 vs 6, p = 0.11). There was no significant association between total lymph nodes and overall survival with both arms combined (HR = 1.00, 95% CI:0.97-1.03, p = 0.87) or in the individual arms alone (RT+Casodex: HR = 1.01, 95% CI:0.97-1.05, p = 0.65; RT+Placebo: HR = 0.98, 95% CI: 0.94-1.03, p = 0.45). There was also no significant association between total lymph nodes and disease-specific survival with both arms combined (HR = 1.00, 95% CI:0.95-1.04, p = 0.84) and in the arms alone (RT+Casodex: HR = 1.00, 95% CI:0.95-1.05, p = 0.92; RT+Placebo: HR = 0.99, 95% CI: 0.92-1.07, p = 0.86). In multivariable analysis performed on the two arms, Gleason score was the only feature associated with worse overall and disease-specific survival, seen only in the RT alone arm. Similar findings were seen when evaluating times to local and distant failure. Conclusions: Lymph node yield in NRG/RTOG 9601 did not show any association with adverse outcomes in the entire cohort, or in either treatment arm alone. The therapeutic benefit of an extensive lymph node dissection in this population remains uncertain. Clinical trial information: NCT00002874.

NRG Oncology/RTOG 9601, a phase III trial in prostate cancer patients: Anti-androgen therapy (AAT) with bicalutamide during and after salvage radiation therapy (RT) following radical prostatectomy (RP) and an elevated PSA

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Background: Previous reports suggested that AAT when combined with salvage RT following RP in patients may improve prostate cancer control outcomes. Methods: Post-RP patients with pT3pN0 or with pT2pN0 and positive margins who had or developed elevated PSA levels from 0.2 to 4.0 ng/ml were randomized on a phase III, double-blind, trial of RT + placebo (64.8 Gy in 36 fractions of 1.8 Gy) vs. RT + AAT (24 months bicalutamide, 150 mg daily) during and after RT. The primary end-point was overall survival. Trial design required 725 patients and provided 80% power to detect a reduction in death rate by at least 28.5% and a 1-sided significance level of 0.046. Results: From 3/98 to 3/03, 761 eligible patients (median age 65) were randomized to RT + AAT (384) or RT + placebo (377). 248 patients (33%) were pT2pN0 and 513 (67%) were pT3pN0. 671 (88%) had a PSA nadir after RP of < 0.5 ng/ml. 649 (85%) had an entry PSA value of <1.6, 112 patients (15%) had an entry PSA of 1.6-4. Median follow up was 12.6 years. Actuarial overall survival at 10 years was 82% for RT plus AAT and 78% for RT + placebo and a hazard ratio of 0.75 (95% CI: 0.58-0.98) with a 1-sided p value of 0.018 (2-sided p = 0.036). The 12-year incidence of PC central-reviewed deaths were 2.3% for RT + AAT and 7.5% for RT + placebo ( p< 0.001).The cumulative incidence of metastatic PC at 12 years was less in the RT + AAT arm, 14% (51 patients), vs. 23% (83 patients) in the RT + placebo arm (p < 0.001). Subgroup analyses of the relative benefits of the addition of AAT to RT are planned and will be presented. Late grade III and IV toxicity were similar in the AAT and placebo arms. The combined grade III and IV toxicities for RT + AAT and RT + placebo were: bladder 7.0% vs. 6.7%, bowel 2.7% vs. 1.6%. Gynecomastia differed significantly by treatment arm, 70% vs. 11%. Conclusions: 24 months of AAT using 150mg bicalutamide daily during and after salvage RT significantly improved long term overall survival and reduced the incidence of metastatic PC and PC death. Support: NCI grants U10CA21661, U10CA180868, U10CA180822, and U10CA37422 and AstraZeneca. Clinical trial information: NCT00002874.

Treatment of bone metastases in a rural setting: The effect of Choosing Wisely

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Background: In 2013, the American Society of Therapeutic Radiology released its list of Choosing Wisely Initiatives. One of these initiatives was to use fraction schemes which may allow less than 10 fractions for the palliation of bony metastatic disease. Such schemes may use one or five fractions to treat an uncomplicated case of bone metastases. This project looks at a rural radiation practice, both before and after a decision was made to employ the Choosing Wisely guidelines when appropriate. Methods: This is a non-randomized, retrospective analysis of 12 months of bone metastases treatments in a single provider practice comparing the 6 months before Choosing Wisely adoption to the 6 months after. A total of 37 consecutive patients, 63 treatment sites were examined. Comparing to a standard 10 fractions of 300 cGy, fifteen treatment fractions were eliminated before adoption, 84 treatment fractions were saved after the guidelines were published. Results: Because of the bias of the practitioner, 14% of the patients received shorter fraction schedules before the Choosing Wisely adoption, 68% of patients after. As far as radiation treatment charges, $12,000 in treatments were saved before adoption, $69,000 in treatments were saved after. Besides the cost savings for the treatments, there were benefits to the patient and to the caregivers. The average patient receiving a shortened fraction schedule saved 145 miles of commuting during the course of their treatment, and saved 5 hours of commuting and treatment time. Assuming that caregivers were employed, a caregiver bringing a patient in for their treatment saved $170.00 in lost wages during the commuting and treatment time. One patient was hospitalized for her treatment and her hospital stay was reduced by the altered fractionation. No patient in the study required retreatment, the minimum follow up period was 6 months. Conclusions: Shorter fraction schemes when used as clinically appropriate do offer savings, not only to health care payers, but also to patients and to patients’ families. Consideration of Choosing Wisely Initiatives has saved patients time and expense as opposed to a similar time period before the initiative. With patients with pain from metastases, these savings are significant.

External irradiation of epithelial skin cancer

A total of 339 consecutively treated, biopsy proven squamous and basal cell carcinomas of the skin treated from January 1966 to December 1986 were retrospectively analyzed to determine the patterns of local recurrence. There were 242 basal cell carcinomas, 92 squamous cell carcinomas, and 5 variants of squamous cell carcinoma in various locations. Radiotherapy was the initial treatment modality in 212 patients and 127 were treated after failing initial surgical excision. Lymph nodes were involved in 1/242 patients (.4%) with basal cell carcinoma, 14/92 patients (15%) with initially treated squamous cell carcinoma, and 20/51 (39%) with recurrent squamous cell lesions. Distant metastasis was found in one patient. Superficial X rays were given to 187 patients, electrons to 57 patients, megavoltage photons to 15, and a combination of modalities to the remainder. Overall local tumor control was achieved in 292 of 339 patients (86%), 220 of 242 (91%) with basal cell and 73 of 97 (75%) with squamous cell carcinoma. Tumor control was closely related to the size of the primary lesion. For lesions less than 1 cm tumor control was 97% (86/89) for basal cell and 91% (21/23) for squamous cell carcinoma. For 1 to 5 cm, tumor control was 87% (116/133) for basal cell and 76% (39/51) for squamous cell carcinoma and for lesions greater than 5 cm, the tumor control was 87% (13 of 15) and 56% (9/16), respectively. Tumor control was related to the modality used to treat the patient in spite of stratification of primary lesion size. For superficial X rays, tumor control was 98% (81/83) for lesions less than 1 cm, 93% (94/101) for lesions 1-5 cm and 100% (5/5) for lesions greater than 5 cm. For electrons tumor control was 88% (14/16), 72% (23/32), and 78% (7/9), respectively. For mixed beams tumor control was 90% (9/10), 76% (32/42), and 64% (9/14), respectively, and for 60Co-4 MV X rays, tumor control was 100% (3/3), 67% (6/9), and 33% (1/3), respectively. Cosmesis and complications were analyzed in 261 patients. An excellent or good cosmetic result was found in 92% (239/261) of the patients. There were 8 of 261 patients (3.1%) with fair and 19 of 261 (7.3%) with poor cosmesis. Cosmesis had an inverse relation to the primary lesion size with 97 of 99 patients (98%) with tumors 1 cm or less, 123 of 140 patients (88%) with lesions 1 to 5 cm and 13 of 16 patients (82%) with larger tumors having excellent or good cosmetic results. Cosmesis is also related to treatment modality.(ABSTRACT TRUNCATED AT 400 WORDS)

Phase I/II study of definitive radiotherapy and chemotherapy (cisplatin and 5-fluorouracil) for advanced or recurrent gynecologic malignancies. Preliminary report

Twenty-three patients with advanced gynecologic malignancy were treated with definitive irradiation and synchronous sensitizing chemotherapy (CT) consisting of cisplatin (CDDP), 50 mg/m2 i.v. rapid infusion, and a 5-day continuous infusion of 5-fluorouracil (5-FU), 750 mg/m2/day. A total of three cycles were administered every 3-4 weeks. Fifteen patients had primary cervical epidermoid carcinoma (three bulky stage IIB, one stage IIIA, ten stage IIIB, one stage IV), four had pelvic recurrences of carcinoma of the cervix, two had endometrial adenocarcinomas (stage IV), and two had vulvar epidermoid carcinoma (one stage III and one stage IV). Radiotherapy (RT) for implantable tumors consisted of 2,000 cGy whole pelvis, 3,000-4,000 cGy split field, and two intracavitary or interstitial insertions, resulting in a total dose of 7,500-8,000 cGy to point A. Three courses of CT were delivered simultaneously with irradiation of the central bulk of tumor: during the first week of whole pelvis RT and with each of the two brachytherapy procedures. Nonimplantable tumors were treated with protracted external beam RT (5,500 cGy tumor dose) and three courses of CT during weeks 1, 4, and 7 of RT. Twenty-one of 23 patients completed RT and 18 of 23 patients completed CT as planned, but half had delays in either RT or CT. Grade 2 or 3 late sequelae consisted of leg edema (one patient), proctosigmoiditis (one patient), bowel obstruction (one patient), vesicovaginal fistula (one patient), and pulmonary embolus (two--one fatal). The incidence of grade 2 and 3 sequelae were 18 and 22%, respectively. With 1-3 years of follow-up evaluation, 12 of 23 (52%) patients are free of disease, and 9 of 22 evaluable patients (41%) have had failure within the pelvis. We conclude that high-dose definitive RT can be delivered with synchronous CDDP and 5-FU at the doses given, with acceptable toxicity. Further study is required to evaluate the impact of radiosensitization on tumor control and late morbidity of therapy. Optimization of irradiation and drug doses as well as the best schedules that may enhance the interaction of these two modalities should be further investigated.

A comparison of two cerebral perfusion tracers, N-isopropyl I-123 p-iodoamphetamine and I-123 HIPDM, in the human

Both N-isopropyl I-123 p-iodoamphetamine (IMP) and I-123 HIPDM have been advocated as radiotracers for assessing regional cerebral perfusion. We compared the biodistribution of the two tracers in 19 patients without evidence of neurological disease. Following intravenous injection, both tracers accumulated initially in the lung. Early after injection the fraction of the total brain uptake was higher for I-123 HIPDM than for I-123 IMP. The peak brain activity for I-123 IMP was higher than for I-123 HIPDM . Brain activity was unchanged with both tracers between 30 and 60 min after injection. Tomographic images were similar in appearance for both tracers. No eye uptake greater than background was observed with either tracer in any patient at 2, 24, and 48 hr. I-123 IMP is superior for tomographic imaging because of its higher brain uptake, whereas I-123 HIPDM may be superior for studies performed during rapid changes in blood flow.

Observations on the clinical value of emission tomography

Data comparing emission computed tomography (ECT), transmission computed tomography (TCT), and radionuclide scintigraphy suggest that in many patients more accurate diagnostic information may be available from emission tomography. ECT was performed during a 4-mo period on 200 of 235 patients referred for brain scans. The data suggest that ECT has a 10% greater sensitivity than scintigraphy, and better specificity. The accuracy of ECT was comparable to that of TCT performed in this group of patients. Selected cases demonstrate areas in which ECT improved lesion detection.

Double-tracer, multiple-organ transaxial emission computed tomography: improved localization and characterization of radiotracer distributions

Transaxial emission computed tomography (ECT) was performed in dogs with experimentally induced abscesses, using 67Ga and several 99mTc-labeled organ-specific radiopharmaceuticals. Superimposition of 99mTc ECT images onto the 67Ga images gave the precise anatomic location of the abnormal foci of 67Ga uptake, correctly localizing a perinephric abscess, a splenic abscess, and a focus of osteomyelitis. This technique also permits further characterization of regions of decreased activity.

Single-photon transaxial emission computed tomography of the heart in normal subjects and in patients with infarction

Resting computerized transaxial tomography was performed after the i.v. injection of thallium-201 in six normal subjects and in five patients who had had myocardial infarctions 3 mo to 4 yr before scintigraphy. Decreased myocardial activity corresponded to the site of previous infarction in all cases and was clearly separated from adjacent myocardium with normal activity. With tomography, the left ventricle was clearly separated from surrounding structures such as the left-ventricular cavity, the lungs, and the liver. This study demonstrates the feasibility for the assessment of myocardial perfusion using single-photon transaxial emmission computed tomography.