"Moderately Hypofractionated" Radiotherapy with a Simultaneously Integrated Boost for Synchronous Treatment of Prostate and Anorectal Cancer

PURPOSE/OBJECTIVE(S)

Data suggest safety and efficacy of 1.8-2.0 Gy per day radiotherapy (RT) with sequential boost regimens for patients with synchronous prostate and anorectal cancers. Emergence of 25-28 fraction (fx) prostate cancer RT regimens has enabled simultaneously integrated boost techniques to treat the prostate and anorectum (HypoRT), but limited reports exist to support the safety or efficacy of this approach. We aimed to assess oncologic outcomes and patient-reported outcomes (PRO)- and physician-reported adverse effects (AEs) of HypoRT for patients with synchronous prostate and anorectal cancers.

MATERIALS/METHODS

This was a retrospective cohort study of patients synchronously diagnosed with prostate and rectal cancer or anal canal squamous cell carcinoma (ASCC) treated with a HypoRT technique and concurrent chemotherapy between 2014-2022. Outcomes included prostate cancer biochemical recurrence (BCR), anorectal cancer recurrence, progression-free (PFS) and overall survival (OS). Acute and late gastrointestinal (GI) and genitourinary (GU) AEs and PRO were prospectively collected using common terminology criteria for AEs (CTCAE) and PRO-CTCAE.

RESULTS

Twelve patients were included. Patients had ECOG 0-1; median age was 71 years (51-82). Rectal cancer (n = 11) characteristics included T3 (91%), N1-2 (73%), M0 (73%); 3 had M1a disease suitable for curative-intent treatment. One patient had T2N1M0 ASCC. Prostate cancer risk groups included low (9%), intermediate (45%), and high/very high risk (46%). HypoRT included 45-50 and 67.5 Gy in 25 fx (33%), 46.8-52 and 70.2 Gy in 26 fx (17%), and 44.8-56 and 70 Gy in 28 fx (50%), to the pelvis-anorectum and prostate. Patients with rectal cancer received concurrent capecitabine. Nine (82%) patients with rectal cancer had surgical resection; 1 was R1. The patient with ASCC received concurrent 5-fluorouracil and mitomycin C. Six patients (50%) received androgen suppression. All patients completed treatment successfully but 1 patient with rectal cancer did require hospitalization with treatment break due to GI AEs. Median follow was 60 months (13-103). Oncologic outcomes and AEs are in the table. No patient experienced prostate cancer BCR or ASCC progression. Four of 11 patients with rectal cancer progressed including 3 distant metastases, each amongst initial M1a patients, and 1 local-regrowth in a patient managed non-operatively.

CONCLUSION

HypoRT can effectively be utilized for patients with synchronous prostate and anorectal cancer. Physician assessed AEs compared favorably with prior data, however, further work is needed to understand differences in physician and patient experience. HypoRT may serve as another suitable option in the management of this complex clinical scenario.

Non-Operative Management of Rectal or Anal Canal Adenocarcinoma: National Cancer Database Analysis of the Impact of Disease, Treatment, and Social Determinants of Health on Overall Survival

PURPOSE/OBJECTIVE(S)

For select patients with rectal or anal canal adenocarcinoma (RA-ACA), a non-operative management (NOM) strategy utilizing definitive radiotherapy (RT) has emerged as an option with the goal to improve quality of life compared with surgical management while maintaining similar oncologic outcomes. Disease and treatment characteristics as well as social determinants of health have been associated with access to care and health outcomes, and we hypothesized that such factors would impact overall survival (OS) amongst patients who received a NOM approach. The purpose of this study was to explore the influence of patient demographics, disease characteristics, and social determinants of health on OS amongst those receiving NOM utilizing the National Cancer Database (NCDB).

MATERIALS/METHODS

We identified patients at least 18 of years of age diagnosed with clinical stage 1-3 RA-ACA from 2004-2018. The NOM cohort included patients who received RT and either refused surgery or surgery was not recommended in their treatment. Patients were excluded if receipt of chemotherapy or RT were unknown, received RT to a site outside of the pelvis, or received palliative-intent treatment. OS was estimated using the Kaplan-Meier method. Univariable and multivariable (MVA) Cox proportional hazards model was used to assess characteristics associated with OS. Analyses were performed using STATA (version 17, College Station, TX). A p<0.05 was considered statistically significant.

RESULTS

A total of 12,409 patients were identified as the NOM cohort. The median OS was 48.8 months (95% CI: 46.8-50.6). On MVA, variables associated with poorer OS included age ≥ 70 vs 50-69, male sex, Charlson-Deyo Score ≥ 1 vs 0, insurance status (no insurance, Medicaid or Medicare vs. private), geographical region (South, Midwest or West vs. Northeast), rural urban density vs metro/urban, treatment in a community facility vs academic, year of diagnosis (2004-2011 vs. 2012-2018), clinical T4 vs T1, clinical N1 or N2 vs N0, and grade 3 vs 1 (all p<0.05). Treatment with a RT dose < 45 Gy vs. 45-54 Gy (HR: 2.24, 95% CI: 2.07-2.44), but not > 55 Gy vs. 45-54 Gy, and omission of chemotherapy (HR: 1.28, 95% CI: 1.16-1.43) were associated with poorer OS.

CONCLUSION

Patient, disease, treatment, and social determinants of health may influence OS amongst patients with RA-ACA who receive a NOM approach. Further work is needed to determine if the influence on OS can be explained, in part, by patients' lack of access to the intense surveillance necessary and/or the potential need for subsequent surgical management. Heightened awareness of these differential outcomes is needed to assist in patient selection and to successfully address barriers in access to optimize outcomes for patients who receive NOM.

Electrocardiogram with Artificial Intelligence Assessment as a Predictor of Cardiac Events and Overall Survival in Patients Receiving Radiotherapy for Esophageal Cancer

PURPOSE/OBJECTIVE(S)

Neoadjuvant (chemo)radiotherapy (RT) has demonstrated an overall survival (OS) benefit in esophageal cancer and constitutes part of the standard of care trimodality therapy. Unfortunately, subsequent cardiac toxicity can reduce the benefit of treatment. Our group aimed to study whether data from electrocardiograms (ECGs) could predict clinical outcomes and cardiac events after RT for esophageal cancer, allowing for identification of and early intervention for patients at high risk for cardiac toxicity.

MATERIALS/METHODS

Included patients received at least 41.4 Gy of pre-operative or definitive photon or proton RT for esophageal cancer from 2015 through July 2022. All ECGs were assessed using a previously validated artificial intelligence assessment for atrial fibrillation (AF) and reduced ejection fraction (rEF) (Noseworthy et al. Lancet 2022). The model determined propensities for the development of multiple cardiac events, including AF and heart failure (HF). Medical records were reviewed for cardiac events and conditions prior to and after RT.

RESULTS

A cohort of 491 patients was assembled, with 301, 121, and 364 patients having an ECG prior to, during, and after RT, respectively. Of these, 84% had malignancy in the lower third of the esophagus and 48% underwent esophagectomy. At last follow-up relative to baseline assessment, patients had increased propensity for rEF (median 0.013, interquartile range (IQR): 0.001-0.038 vs. median 0.022, IQR: 0.011-0.074, p < 0.0001) and AF (median 0.16, IQR: 0.04-0.40 vs. median 0.048, IQR: 0.01-0.19, p < 0.0001). Increases in AF propensity were associated with reduced OS (hazard ratio (HR) = 1.10 per 0.1 increase, 95% confidence interval (CI): 1.03-1.17, p = 0.0071). Baseline rEF propensity was predictive of future HF events (HR = 1.14, 95% CI: 1.07-1.22, p < 0.001) for all patients or after excluding the 172 (35%) patients with baseline HF (HR = 1.45, 95% CI: 1.19-1.76, p < 0.001). Among patients who did not have HF prior to radiotherapy, the development of HF was associated with reduced OS (HR = 1.60, 95% CI: 1.10-2.32, p = 0.014). Currently available cardiac dosimetric parameters, including heart mean/max doses, did not significantly correlate with cardiac outcomes. Patients who underwent esophagectomy had improved OS (HR = 0.62, 95% CI: 0.47-0.82, p = 0.0008) and were not more likely to develop cardiac toxicity.

CONCLUSION

This analysis suggests that chemoradiotherapy for esophageal cancer can have significant impacts on a patient's propensity for cardiac events, which are associated with reduced OS. ECGs carry the potential to identify patients at greater risk for such events, and baseline ECGs with artificial intelligence assessment could select patients for increased surveillance or early intervention to further optimize the therapeutic ratio of RT.

Patient-Reported Adverse Effects in 15-Fraction Pancreatic Cancer Radiation Therapy

PURPOSE/OBJECTIVE(S)

Fifteen-fraction radiotherapy (RT) regimens have emerged as a standard option in the treatment of patients with pancreas cancer. Patient-reported outcomes (PROs) during and after pancreas cancer RT have not been well characterized. There is an even greater paucity of data among patients treated with 15-fraction regimens. We aimed to characterize gastrointestinal (GI) PROs in a cohort of patients treated with 15-fraction pancreas RT.

MATERIALS/METHODS

This was an IRB-approved retrospective cohort study including patients with primary pancreas tumors treated with pre-operative or definitive 15-fraction RT from 2013 to 2022. PROs, including anorexia, nausea, diarrhea, stool incontinence, and abdominal pain, were prospectively collected and characterized per PRO-common terminology criteria for adverse events (PRO-CTCAE). Acute PROs were defined as occurring during RT through 110 days post-RT but prior to oncological surgery. Grade 3 or 4 PROs were respectively scored as "quite a bit" or "very much" in symptom interference questions, "frequently" or "almost constantly" in symptom frequency questions, and "severe" or "very severe" in symptom severity questions.

RESULTS

A total of 330 patients were analyzed. Patient characteristics included a median age of 67 years (IQR: 60 - 72), ECOG 0-1 (96%), and male sex (56%). Most patients had pancreatic ductal adenocarcinoma (96%). Resectability status included resectable (12%), borderline resectable (46%), and locally advanced (42%). 37% had lymph node involvement. 97% of patients received neoadjuvant chemotherapy and 98% received concurrent chemotherapy, most commonly with 5-fluorouracil or capecitabine (88%) or gemcitabine (11%). 99% were treated with intensity modulated RT. Median RT dose was 4500 cGy (IQR 4500 - 4500) to gross disease with margin and 3750 cGy (IQR 3750 - 3750) to elective nodal regions. 59% proceeded with oncologic resection. Grade 3 or higher acute PROs are demonstrated in the table.

CONCLUSION

Often considered more sensitive than physician assessments, PROs provide vital metrics that allow for a better understanding of the patient experience during cancer treatment. We report a comprehensive assessment of prospectively collected PROs per standardized PRO-CTCAE with the goals of raising awareness of the patient experience during 15-fraction pancreas cancer RT and helping guide future clinical trial designs focused on patient quality of life endpoints.

Clinical Outcomes for Chest Wall Ewing Sarcoma: A Multi-Center Single Institution Experience

PURPOSE/OBJECTIVE(S)

We report tumor and treatment characteristics, oncologic outcomes, and treatment-associated toxicities in a cohort of chest wall Ewing sarcoma (cwES) patients treated at a single tertiary care institution.

MATERIALS/METHODS

After IRB approval, patients with cwES treated from 1997-2022 were retrospectively reviewed. Patient, tumor, treatment, outcomes, and toxicity data were abstracted. Local control (LC), progression-free survival (PFS), and overall survival (OS) were defined from end of treatment and assessed using the Kaplan-Meier method. Log-rank test and unadjusted Cox models were performed to determine factors associated with outcomes.

RESULTS

The cohort includes 45 patients. Median age at diagnosis was 19.8 years (range: 3.5 - 57.8 years). Five patients (11.1%) presented with pleural effusion and eight patients with lung metastases (17.8%). Two (4.4%) patients had metastatic disease outside the thorax. Median tumor volume (TV) was 138.6 mL (range: 3.0-6762.0 mL). All patients received VDC/IE chemotherapy. LC modality was surgery (S) in 21 patients (47%), radiation therapy (RT) in 5 (11%), and S+RT in 19 (42%). Median TV was larger in S+RT patients (319.4 mL, range: 5.3-6761.9 mL) compared to RT (152.3 mL, range: 20.4-366.9 mL) or S (70.4 mL, range: 3.1-1037.8 mL) (p = 0.03). R0 and R1 resections were performed in 36 (90%) and 4 (10%) patients, respectively. Proton beam therapy was used in 15 (63%) patients. Median dose was 50.40 Gy (range: 34.2 - 60 Gy) in 28 fractions to the primary tumor or post operative bed. Median dose for hemithorax (1 patient, 2.2%) and whole lung irradiation (7 patients, 15.6%) was 15.0 Gy (range: 15.0-15.0 Gy) in 10 fractions. Median follow-up was 2.38 years (range: 0 - 21.90 years). Five-year LC, PFS, and OS for all patients was 77.9% (95% CI, 65.3 - 92.9%), 54.2% (95% CI, 39.9 - 73.5%), and 63.5% (95% CI, 49.3 - 81.8%), respectively. In patients with localized disease, 5-year LC, PFS, and OS were 82.4% (95% CI, 67.9-99.8%), 66.4% (95% CI, 49.7-88.8%), and 71.3% (95% CI, 54.2-93.9%), respectively. Two-year LC by modality was 100% for RT (95% CI, 100-100%), 84.2% (95% CI, 69.3- 100%) for S and 73.3% (95% CI, 54 - 99.5%) for S+RT (p = 0.51). On univariate analysis, TV ≥ 200 mL was associated with a significantly worse 5-year OS (49.5%, TV ≥ 200 mL vs. 80.8%, TV < 200 mL; HR 4.44, p = 0.032) and PFS (35.2%, TV ≥ 200 mL vs. 76%, TV < 200 mL; HR 3.55, p = 0.025). TV ≥ 200 mL trended towards worse 5-year LC: 69.2% for TV ≥ 200 mL versus 81.5% for TV <200 mL [HR 2.26(95% CI 0.49 - 10.47), p = 0.287]. Overall, low rates of grade ≥2 toxicity were observed: 4 (8.9%) fatigue, 4 (8.9%) radiation dermatitis, 1 (2.2%) chyle leak, 3 (6.6%) scoliosis, 4 (8.9%) infection, 1 (2.2%) pneumonia, and 1 (2.2%) chest wall deformity.

CONCLUSION

RT is a safe, effective local therapy for small to moderate cwES tumors. Patients with TV ≥ 200 mL had significantly worse survival outcomes and an inferior LC rate. This suggests large cwES tumors may benefit from an aggressive multi-modality approach.

Determining the Minimal Clinically Important Difference of the FACT-E to Evaluate the Change in the Quality of Life of Patients with Esophageal Cancer Treated with Curative Radiotherapy

PURPOSE/OBJECTIVE(S)

Patients with esophageal cancer (EC) are often treated with radiotherapy (RT). The Functional Assessment of Cancer Therapy-Esophageal (FACT-E) is a health-related quality of life (QOL) instrument validated in patients with EC. The aim of this study was to determine the minimal clinically important difference (MCID) for FACT-E subscales, to allow for meaningful evaluation of the effect of RT on EC patient's QOL.

MATERIALS/METHODS

We evaluated patients with EC, treated with curative intent RT, who completed the FACT-E at baseline and end of treatment (EOT). We calculated the MCID for the FACT-E subscales using anchor-based and distribution-based approaches. In the anchor-based approach we determined improvement and deterioration based on the overall health assessment from the PROMIS-10 as the anchor. We modeled the change in domain scores with age-adjusted regressions to determine the difference in classifications. For distribution-based analysis, we considered 0.3 and 0.5 standard deviation (SD). We averaged MCID for improvement and deterioration separately across timepoints, by approach, and we report MCID ranges as the minimum and maximum values across methods.

RESULTS

Our cohort included 210 patients with EC, 96.7% white, 85.7% males, and 32.9% treated with photon with a median dose of 50 Gy (IQR 50-50) and a median fraction number of 25(IQR 25,25). The median age at RT was 67.6 years (IQR 60.9,73.7). The social domain had the lowest MCID (deterioration and improvement 0.9-1.9), while the widest MCID range, proportionally to the measure, was associated with the Fact-E total score (2.1-5.6 for improvement, and 3.7-5.6 for deterioration). MCID estimates from 0.3 SD were in exact agreement with the anchor-based deterioration estimates for the physical domain (2.3), and improvement estimates for the Trial Outcome Index (6.1).

CONCLUSION

We determined the MCID for the FACT-E domains, using a combination of anchor- and distribution-based approaches. These findings are critical to determine whether there is meaningful change in the QOL of individuals with EC treated with curative RT.

Sensitivity of the PROMIS-10 for Capturing Radiation-Related Quality of Life Changes

PURPOSE/OBJECTIVE(S)

Patient reported outcomes (PROs) are becoming more common when assessing the effects of radiotherapy (RT). The aim of this study was to assess the sensitivity of the Mental and Physical domains of the Patient-Reported Outcomes Measurement Information System 10 (PROMIS-10) to radiotherapy and determine what predictors were associated with change in quality of life.

MATERIALS/METHODS

Patients, regardless of cancer type, were enrolled on a multi-site prospective registry. Inclusion criteria included curative radiotherapy and completion of the PROMIS-10 prior to treatment (Baseline) and at End of Treatment (EOT). To assess the strongest predictors of change in the T score of mental and physical health, we included 14 demographic characteristics and treatment variables in a multivariable stepwise regression.

RESULTS

A total of 7,586 patients were eligible for the analysis. The median age was 65 (range 18-94), 54% were males, and 94% were white. A majority received photons (62.5%) and the others received protons (37.5%) with an average dose of 52.3 Gy (range 20-80 Gy) over an average of 22.6 fractions (range 1-66). Patient disease sites were sub-grouped into 12 categories: Breast (25.5%), GU (23.0%), H&N (11.1%), CNS (8.5%), Pancreas-Biliary (6.7%), Thoracic (5.7%), Soft Tissue/Bone (5.0%), Esophagus-Gastric (4.7%), Colorectal-Anus (4.4%), Heme/Lymph (2.6%), GYN (1.8%), and Skin/Melanoma (1.0%). For both outcomes, the model selected disease group as an important predictor and it explained the most variance in the outcome compared to the rest of the predictors. When probing the effect of disease group, H&N, Esophagus-Gastric, Skin/Melanoma, and Colorectal-Anus had the largest mean decrease in quality of life for both domains. For mental health, the model also selected radiation type. Patients treated with protons indicated a bigger decrease in mental health compared to patients treated with photons (b = 0.43, 95% CI: -0.01, 0.69). For physical health, the model selected total fractions, ethnicity, and T stage. As number of fractions increased, the physical health change scores became more negative, on average (b = -0.03, 95% CI: -0.05, -0.01). Hispanic/Latino patients indicated a smaller decrease in physical health compared to White (b = -1.50, 95% CI: -2.60, -0.40) and Unknown ethnicity patients (b = -1.82, 95% CI: -3.36, -0.27). Finally, patients with a T stage of 3 or greater indicated a smaller decrease in physical health than patients with a T stage less than 3 (b = 0.76, 95% CI: 0.35, 1.16).

CONCLUSION

The PROMIS-10 did not capture significant change for patients undergoing curative radiotherapy except for patients with Head & Neck, Esophagus-Gastric, Skin, and Colorectal-Anus cancer. Further analyses should explore which patients experience the greatest change in quality of life within disease group.

Single Institutional Experience Using Radiation Therapy in the Treatment of Neuroendocrine Tumor Primary and Metastatic Lesions

PURPOSE/OBJECTIVE(S)

The role of radiation therapy (RT) in the treatment of patients with neuroendocrine tumors (NETs) has not been well established. We aim to report on our experience using RT as part of curative or palliative treatment in patients with NET.

MATERIALS/METHODS

This was an IRB approved single-institutional retrospective cohort study including patients with NET who received curative- or palliative-intent RT from 2013-2022. Outcomes included cumulative incidence of local progression (LP) and overall survival (OS). Univariate and multivariate methods were used to assess disease and treatment characteristics associated with outcomes. RT dose was converted to biologically effective dose (BED10), assuming α/β = 10 Gy.

RESULTS

Sixty-six patients who received treatment to 89 total lesions were included for analysis. The median age at RT was 56 years (range: 20-95). ECOG performance status was 0-1 in 49 and 56% were male. Primary tumor origin included: 28 pancreas, 12 lung, 8 small intestine, 5 colorectal, 2 stomach, and 11 unknown/other primary cancers. Tumor grade included 1 (62%), 2 (1%), 3 (17%) or unknown (18%). 20% were functional. 43% of patients had metastatic disease at diagnosis, 24 were initially M0 and developed M1 disease in their disease course, and 12 remained M0. RT was delivered to the primary tumor (59%) or metastatic sites (41%). Treatment was either curative-intent (37%), including "curative" intent oligometastasis direct therapy, or palliative-intent (63%). For the 27 patients with M1 disease at time of RT, 1 had all sites controlled by local therapies at the time of RT. The location of the treated lesions included 17 pancreas, 13 bone, 12 thorax, 4 colorectal, 3 small bowel, and 15 other. Median RT dose and number of fractions were 30 Gy (IQR: 20-45) and 5 (IQR: 5-15). The median BED10 was 48 (IQR: 28-65) for all lesions and 60 (IQR: 58-69) for lesions treated curatively. 21 (32%) patients received concurrent systemic therapy with RT. The median follow-up per patient and per lesion were 15 months (IQR: 6-33) and 13 months (IQR: 5-28). The median OS was 34.5 months (95% confidence interval [CI]: 16.6-NE). The 3-year cumulative incidence of local progression was 15% (95% CI: 8-28%). BED10 was not associated with LP.

CONCLUSION

These data support the use of RT as a highly effective local treatment modality in the care of patients with either localized or metastatic NET.

Assessing the Sexual Health of Female Survivors of Pelvic Malignancies after Radiotherapy

PURPOSE/OBJECTIVE(S)

To assess patient-reported sexual health outcomes of female survivors of pelvic malignancies after radiotherapy (RT).

MATERIALS/METHODS

Female patients treated with curative intent RT for pelvic malignancies between 2013 and 2019 were surveyed electronically post-RT using the PROMIS Sexual Function and Satisfaction Full Profile and Female Sexual Distress Scale-Revised questionnaires. Cervical and vaginal cancers were grouped together due to the similar treatment characteristics.

RESULTS

Surveys were sent to 544 patients, and 53 (10%) completed the questionnaires. Respondents included survivors of anal canal (N = 11), cervical or vaginal (N = 10), uterine (N = 30), and vulvar cancers (N = 2). The median age of patients at the time of treatment was 60 years (range 31,77). The median time between RT and survey completion was 6 years (range 3,9). A total of 22 (42%), 17 (32%), and 14 patients (26%) were treated with brachytherapy (BT), external beam RT (EBRT), or a combination of EBRT and BT, respectively. Of respondents, 96% were free of disease recurrence. Sexually active was defined as partaking in sexual activity within 30 days of survey response. Patients were stratified by age greater than or less than 52 at time of RT, representing the average age of menopause. A total of 30 patients (57%) had at least somewhat interest in sex. There was no difference in the proportion of patients who had at least somewhat interest in sex over 52 years compared to those 52 and (54% vs 67%, p = 0.424). A total of 39 patients (74%) were sexually active, and of those 30 (77%) were over the age of 52 at the time of RT. Of sexually active patients, 28 (72%) reported some, quite a bit, or a lot of satisfaction with their sex lives, whereas the remaining 11 (28%) reported having none or a little bit of satisfaction with their sex lives; the proportion of those with at least some satisfaction with their sex lives did not differ between those who were over or under 52 years at the time of RT (73% vs 67%, p = 0.697). Satisfaction with sex life differed by site of malignancy with 71% cervical or vaginal, 44% anal canal, 86% uterine, and 0% vulvar patients reporting at least some satisfaction (p = 0.043). Patients treated for anal canal cancer tended to have quite a bit or a lot of vaginal discomfort during sex (78%), compared to those treated for cervical/vaginal (29%), or endometrial (18%) cancers (p = 0.006). There was no difference in patients feeling frequently or always stressed about sex between those who were sexually active compared to those who were not (13% vs 14%, p = 0.890). Patients 52 or under at the time of RT were more likely to feel frequently or always stressed about sex compared to those receiving RT over the age of 52 (42% vs 5%, p<0.001).

CONCLUSION

In our cohort, the majority of female survivors of pelvic malignancies were sexually active post-RT, and this important topic warrants further investigation.

Results of a pooled analysis of IOERT containing multimodality treatment for locally recurrent rectal cancer: Results of 565 patients of two major treatment centres

OBJECTIVE

Aim of this study is analysing the pooled results of Intra-Operative Electron beam Radiotherapy (IOERT) containing multimodality treatment of locally recurrent rectal cancer (LRRC) of two major treatment centres.

METHODS AND MATERIALS

Five hundred sixty five patients with LRRC who underwent multimodality-treatment up to 2010 were studied. The preferred treatment was preoperative chemo-radiotherapy, surgery and IOERT. In uni- and multivariate analyses risk factors for local re-recurrence, distant metastasis free survival, relapse free survival, cancer-specific survival and overall survival were studied.

RESULTS

Two hundred fifty one patients (44%) underwent a radical (R0) resection. In patients who had no preoperative treatment the R0 resection rate was 26%, and this was 43% and 50% for patients who respectively received preoperative re-(chemo)-irradiation or full-course radiotherapy (p < 0.0001). After uni- and multivariate analysis it was found that all oncologic parameters were influenced by preoperative treatment and radicality of the resection. Patients who were re-irradiated had a similar outcome compared to patients, who were radiotherapy naive and could undergo full-course treatment, except the chance of local re-recurrence was higher for re-irradiated patients. Waiting-time between preoperative radiotherapy and IOERT was inversely correlated with the chance of local re-recurrence, and positively correlated with the chance of a R0 resection.

CONCLUSIONS

R0 resection is the most important factor influencing oncologic parameters in treatment of LRRC. Preoperative (chemo)-radiotherapy increases the chance of achieving radical resections and improves oncologic outcomes. Short waiting-times between preoperative treatment and IOERT improves the effectiveness of IOERT to reduce the chance of a local re-recurrence.

Outcomes following surgery without radiotherapy for rectal cancer

BACKGROUND

This study determined survival and recurrence rates following curative resection of rectal cancer without radiotherapy.

METHODS

This was a retrospective review of the Mayo Clinic database of patients with rectal cancer treated with curative intent using surgery alone from 1990 to 2006. Patients who received neoadjuvant chemotherapy or radiation therapy and those who had any postoperative radiotherapy were excluded. Details were collected from the database and patient records using a protocol approved by the institutional review board.

RESULTS

Some 655 consecutive patients with rectal cancer treated with curative intent using surgery alone were identified; 397 had stage I disease, 125 stage II and 133 stage III. Four hundred and nine patients underwent anterior resection (AR) and 246 abdominoperineal resection (APR). Median follow-up was 62 months. The 5-year rate of local recurrence was 4·3 per cent, disease-free survival 90·0 per cent and cancer-specific survival 91·5 per cent. Stage-specific and all-stage disease-free survival did not differ significantly between AR and APR. The 5-year cumulative local recurrence rate was lower following AR than APR (3·6 versus 5·5 per cent; P = 0·321). There were only two patients with positive margins and type of operation was not significant on multivariable analysis.

CONCLUSION

Well-performed, standardized APRs have similar local recurrence to AR. Radiation therapy may not confer much additional benefit.

Multimodality therapy including surgical resection (SR) and intraoperative electron radiotherapy (IOERT) for locoregionally recurrent (LRR) or advanced primary malignancies of the urinary bladder (UB) or ureter

277

Background: For patients (pts) with LRR or advanced primary tumors of the UB or ureter, limited therapeutic options exist. Outcomes of combined SR and IOERT are reported here.

Methods: From 1983 to 2009, a total of 17 pts with urothelial (16 pts) or squamous cell carcinoma (1 pt) of the UB (n=13) or ureter (n=4) were treated with SR and IOERT. Pts had LRR after radical cystoprostatectomy or nephroureterectomy (n=15) or advanced primary tumor (n=2). Extent of SR was R0 (microscopic negative margins), R1 (microscopic positive margins), and R2 (gross residual tumor) in 7, 1, and 9 pts, respectively. After maximal SR, IOERT was delivered to the tumor bed. Median IOERT dose and energy delivered were 12.5 Gy (range; 10-20) and 9 MeV (range; 6-18), respectively, with 1 (n=15), 2 (n=1), or 3 (n=1) IOERT fields. Sixteen pts also received perioperative external beam radiotherapy (EBRT) with a median dose of 50.4 Gy (range; 21.6- 60). Five pts received concurrent chemotherapy (CT) with perioperative EBRT. Overall (OS), disease-free survival (DFS) and relapse patterns were estimated from the date of SR and IOERT using the Kaplan-Meier method.

Results: The median pt age was 63 years (yrs) (range; 51-76). The median follow-up of surviving pts was 3.6 yrs (range; 1.1-10.0). OS and DFS at 1, 2, and 5 yrs were 53%, 31%, and 16%, and 24%, 18%, and 18%, respectively. Central (within the IOERT field), locoregional (tumor bed or first echelon draining lymphatics), and distant relapse at 2 yrs were 15%, 49%, and 67%, respectively. Seven pts received systemic CT after relapse. Mortality within 30 days of SR and IOERT was 0%. Two pts (12%) experienced grade 4-5 (NCI-CTCAE v. 4) toxicity potentially related to the multimodality therapy.

Conclusions: For pts with LRR or advanced primary tumor of the UB or ureter, this multimodality therapy including SR and IOERT resulted in durable OS and DFS in a small but significant number of pts. Both LRR and distant relapse were common, indicating a need for more effective systemic therapy along with more refined locoregional therapy.

No significant financial relationships to disclose.

Two-year outcomes of RTOG 0529: A phase II evaluation of dose-painted IMRT in combination with 5-fluorouracil and mitomycin-C for the reduction of acute morbidity in carcinoma of the anal canal

368

Background: 5-Fluorouracil (5FU) and mitomycin-C (MMC) chemoradiation for anal cancer is associated with high rates of acute morbidity. We have previously shown that dose-painted IMRT (DP-IMRT) significantly reduces grade 3+ GI and dermatologic acute toxicity, as compared to the RTOG 9811 5FU/MMC arm, which used non-conformal radiation techniques. We now report on the two-year outcomes of this DP-IMRT approach.

Methods: T2-4N0-3M0 anal canal cancers received 5FU (1,000 mg/m2/day 96 hour infusion) and MMC (10 mg/m2 bolus) days 1 and 29 of DP-IMRT prescribed as follows - T2N0: 42 Gy elective nodal and 50.4 Gy anal tumor planning target volumes (PTVs), 28 fractions; T3-4N0-3: 45 Gy elective nodal, 50.4 Gy ≤ 3 cm and 54 Gy > 3 cm metastatic nodal and 54 Gy anal tumor PTVs, 30 fractions. The following two-year outcomes were assessed: local-regional (LRF) and colostomy failures (CF) using the cumulative incidence method, and disease-free (DFS), overall (OS) and colostomy-free survivals (CFS) using the Kaplan-Meier method.

Results: Of 63 accrued patients, 52 were analyzable. Median age was 58 years; 81% female; 54% stage II; 25% IIIA; 21% IIIB. Median follow-up was 23.2 months (0.2-33). Two-year LRF, CF, DFS and 95% confidence intervals are 20% (9%, 31%), 8% (0.4%, 15%) and 77% (62%, 86%), respectively. The causes of death for the 7 patients that died are: anal cancer in 5, morbidity in one and second primary outside the radiation field in one. Two-year comparison data from the RTOG 9811 5FU/MMC arm are shown in the table below.

Conclusions: DP-IMRT with 5FU/MMC for the treatment of anal canal cancer yields similar two-year outcomes as the RTOG 9811 conventional radiation, 5FU/MMC arm. Because of the associated acute toxicity sparing, DP-IMRT will be used as the platform, and may allow for radiation dose escalation, in future RTOG anal canal trials. Supported by RTOG U10 CA21661, CCOP U10 CA3742 and ATC U24 CA 81647 NCI grants.

[Table: see text]

No significant financial relationships to disclose.

Long-term update of U.S. GI Intergroup RTOG 98-11 phase III trial for anal carcinoma: Comparison of concurrent chemoradiation with 5FU-mitomycin versus 5FU-cisplatin for disease-free and overall survival

367

Background: On initial publication of GI Intergroup RTOG 98-11, concurrent chemoradiation with 5FU+mitomycin (MMC) decreased colostomy failure (CF) vs induction plus concurrent 5FU+cisplatin (CDDP), but did not significantly impact disease free or overall survival (DFS, OS). The intent of the current analysis is to determine the long-term impact of treatment on survival (DFS, OS, colostomy-free [CFS]), CF and relapse (local-regional [LRF], distant [DM]) in this patient group.

Methods: Stratification factors included gender, clinical node status, and primary size. DFS/OS were estimated univariately by Kaplan-Meier method and treatment arms compared by log-rank test. Time to relapse/CF were estimated by cumulative incidence method and treatment arms compared by Gray's test. Multivariate analyses were done with Cox proportional hazard models to test for treatment differences, adjusting for stratification factors.

Results: Of 682 patients accrued, 649 were analyzable for outcomes. As seen in the table, 5-yr DFS and OS were statistically better for RT+5FU/MMC vs RT+5FU/CDDP (67.7 v 57.6%, p=.0.0045; 78.2 v 70.5%, p=0.021) with trends toward statistical significance for CFS, LRF, and CF (71.8 v 64.9%, p=0.053; 20 v 26.5%, 11.9 v 17.3%, p=0.092 and 0.075). Similar results were seen in multivariate analysis.

Conclusions: Concurrent chemoradiation with 5FU-MMC has a statistically significant impact on DFS and OS vs induction + concurrent 5FU-CDDP and borderline significance for CFS, CF and LRF. Therefore, RT+5FU/MMC remains the preferred standard of care. Potential strategies to improve outcomes include treatment intensification and individualized molecular-based treatment. Supported by RTOG grant U10 CA21661 and CCOP grant U10 CA37422 from the National Cancer Institute (NCI).

[Table: see text]

No significant financial relationships to disclose.

Impact of endoscopic ultrasonography and physician specialty on the management of patients with esophagus cancer

While endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (EUS-FNA) are the most accurate techniques for locoregional staging of esophageal cancer, little evidence exists that these innovations impact on clinical care. The objective on this study was to determine the frequency with which EUS and EUS-FNA alter the management of patients with localized esophageal cancer, and assess practice variation among specialists at a tertiary care center. Three gastroenterologists, three medical oncologists, three radiation oncologists and four thoracic surgeons were asked to independently report their management recommendations as the anonymized staging information of 50 prospectively enrolled patients from another study were sequentially disclosed on-line. Compared to initial management recommendations, that were based upon history, physical examination, upper endoscopy and CT scan results, EUS prompted a change in management 24% (95% CI: 12-36%) of the time; usually to a more resource-intensive approach (71%), for example from recommending palliation to recommending neoadjuvant chemoradiation therapy. EUS-FNA plus cytology results altered management an additional 8% (95% CI: 6-15%) of the time. Agreement between specialists ranged from fair (intraclass correlation [ICC=0.32) to substantial (ICC=0.65); improving with additional information. Among specialists, agreement was greatest for patients with stage I disease. EUS and EUS-FNA changed patient management the most for patients with stages IIA, IIB or III disease. EUS, with or without FNA, significantly impacts the management of patients with localized esophageal cancer. With respect to the optimal treatment for each patient, agreement among physicians incrementally increases with endoscopic ultrasound results. Specialty training appears to influence therapeutic decision-making behavior.

Intraoperative radiotherapy for treatment of locally advanced and recurrent esophageal and gastric adenocarcinomas

Intraoperative radiotherapy (IORT) allows delivery of radiotherapy doses in excess of those typically deliverable with conventional external beam radiotherapy. IORT has potential utility in clinical situations, such as treatment of esophageal and gastric malignancies, in which the radiation tolerance of normal organs limits the dose that can be given with conventional radiotherapy techniques. We reviewed the records of 50 patients who received IORT for locally advanced primary or recurrent gastric or esophageal adenocarcinomas deemed unresectable for cure. IORT was given as a single fraction of electron beam radiotherapy (10-25 Gy) after maximal tumor resection: R0 in 42%, R1 in 46%, and R2 in 12%. Forty-eight patients also received external beam radiotherapy (8-55 Gy), 46 received radiosensitizing chemotherapy, and nine received systemic chemotherapy after radiotherapy. Outcomes were estimated with Kaplan-Meier analysis. Median survival was 1.6 years. Overall survival at 1, 2, and 3 years was 70%, 40%, and 27%. Of 42 patients who died, 37 died from cancer progression and three from multifactorial treatment toxicity. Median survival for patients with recurrent disease versus primary disease was 3.0 years versus 1.3 years (P < 0.05), with a delay of metastatic failure in patients with recurrent tumors (P = 0.06). At 3 years, distant metastatic failure was 79%, local failure was 10%, and regional failure was 15%. IORT for locally advanced primary or recurrent gastric malignancies effectively decreases the risk of local failure. For patients with isolated local recurrences, IORT may be effective salvage therapy. However, more effective systemic therapy is needed as a component of treatment.

Sphincter-preserving radiation therapy for rectal cancer: a simulation study using three-dimensional computerized technology

BACKGROUND

The acquisition of detailed computerized tomography (CT) imaging at the time of simulation, along with three-dimensional (3D) treatment planning software has been integrated with radiation delivery hardware to create the modality known as 3D conformal radiotherapy (3DXRT). This approach provides, in theory, a means to selectively subtract the anal sphincter from the high-dose field of irradiation in patients with stage II and III adenocarcinomas of the mid-rectum scheduled for low anterior resection (LAR).

HYPOTHESIS

Implementation of 3DXRT with sphincter blocking may be a feasible strategy to reduce the dose of radiation distributed to the anal canal without reduction in the dose distribution to the gross tumour volume (GTV) plus adequate margins.

METHODS

Pretreatment simulation CT scans of 10 patients with rectal cancers located between 5 and 10 cm from the anal verge were retrieved from a computerized database. Radiation oncologists and colorectal surgeons defined the contours of the GTV and the anal sphincter, respectively, on successive CT scan slices. These contours provided the volumetric data required to quantify dose distribution and compute dose-volume histograms. The standard mode of pelvic irradiation planned with CT simulation was compared with a 'virtual CT simulation' approach, in which a sphincter block was added to the protocol.

RESULTS

The mean distance of tumours from the anal verge was 6.3 cm. In the virtual simulation treatment plan, a 2-cm margin separated the sphincter block from the lower limit of the GTV. The mean volume of the anal sphincter was 16.1 +/- 3.5 cm(3). The dose distributed to the GTV in the real plan and in the virtual simulated block plan were 51.7 +/- 1.4 and 51.6 +/- 1.4 Gy respectively (P = 0.85). By comparison the mean dose distributed to the anal sphincter was dramatically reduced by using a sphincter block (33.2 +/- 12 Gy vs 6.4 +/- 4.1 Gy, P < 0.001).

CONCLUSION

During a course of radiotherapy for most low- or mid-rectal cancers, the anal canal is included within the field of irradiation with a mean dose distribution to the sphincter of 33 Gy. Evaluation of 3DXRT with full sphincter block (mid-rectum) and partial sphincter block (distal rectum) is a feasible strategy to decrease the volume of anal sphincter carried to full dose without reduction in dose to the GTV. This approach, by minimizing treatment-induced damage to the anal sphincter, might improve functional outcome of LAR.

Intergroup RTOG 98–11: A phase III randomized study of 5-fluorouracil (5-FU), mitomycin, and radiotherapy versus 5-fluorouracil, cisplatin and radiotherapy in carcinoma of the anal canal

4009

Background: An ∼65% 5-year disease-free-survival (DFS) rate from 5-FU/mitomycin/radiation for anal carcinoma needs improvement. Methods: A phase III randomized trial compared 5-FU (1,000mg/m2 days 1–4 and 29–32) plus mitomycin (10mg/m2 days 1 and 29) and radiation (45 to 59 Gy) (Arm A) to 5-FU (1,000mg/m2 days 1–4, 29–32, 57–60 and 85–88) plus cisplatin (75mg/m2 on days 1, 29, 57 and 85) and radiation (45 to 59 Gy; start day=57) (Arm B) in anal carcinoma patients. Stratification included gender, clinical N status and tumor diameter. Primary endpoint was DFS. Statistical power was 80% with two-sided test to detect 10% DFS increase for Arm B. Results: Of 682 patients accrued, 598 were analyzable. Most unanalyzed patients’ data are early. Patient characteristics were balanced. Median age was 55 years, women predominated (69%), 27.5% had >5 cm tumor diameter and 26% had clinically N+ cancer. Preliminary 5-year estimated DFS was 56% for Arm A and 48% for Arm B (p=0.28) and 5-year estimated overall survival was 69% for both arms (p=0.24). Men(p=0.04), clinically N+ cancer (p<0.0001) and tumor diameter >5 cm (p=0.005) independently prognosticated DFS in a multivariate analysis. 5-year colostomy rate was 10% for Arm A and 20% for arm B(p=0.12). Grade 3/4 toxicity rates: non-hematologic=76% for Arm A and 75% for Arm B but hematologic=67% for Arm A and 47% for Arm B(p=0.0004). Conclusions: In Intergroup-98–11, induction 5-FU/cisplatin followed by 5-FU/cisplatin/radiation failed to improve DFS compared to the standard treatment, 5-FU/mitomycin/radiation. Supported by RTOG U10 CA21661, CCOP U10 CA37422, Stat U10 CA32115.

No significant financial relationships to disclose.

Long-term follow-up of radical retropubic prostatectomy for prostate cancer

OBJECTIVES

The ultimate outcome of patients after radical prostatectomy is often predicted from statistical projections of short-term follow-up. Only actual long-term follow-up can demonstrate true outcome.

METHODS

One hundred thirty-one patients underwent retropubic prostatectomy for clinically organ confined prostate cancer and have been followed for a minimum of 22.5 years. Preoperatively, all but 12 had clinically palpable cancer.

RESULTS

Overall survival in these patients was similar to an age-matched population, with 65% alive at 15 years, and 23% alive at 25 years. Thirty-seven percent of the patients recurred and 24% of all the patients died of prostate cancer. For patients with pathologically organ confined disease, 27% recurred, while those with extension outside the gland or positive nodes had an 83% recurrence rate. Although, the median time to recurrence was 7 years, recurrences occurred at a steady-state throughout the length of follow-up. Patients with higher grade tumors, even if organ confined, were significantly more likely to recur.

CONCLUSIONS

In a cohort of patients treated with radical prostatectomy for predominantly palpable disease, long-term follow-up (79% deceased) reveals that 37% will recur and 24% will die of prostate cancer. Almost half the recurrences occurred after 10 years, indicating that reports with shorter follow-up will underestimate the recurrence rate.

Intraoperative irradiation for locally recurrent colorectal cancer in previously irradiated patients

PURPOSE

Information in the literature regarding salvage treatment for patients with locally recurrent colorectal cancer who have previously been treated with high or moderate dose external beam irradiation (EBRT) is scarce. A retrospective review was therefore performed in our institution to determine disease control, survival, and tolerance in patients treated aggressively with surgical resection and intraoperative electron irradiation (IOERT) +/- additional EBRT and chemotherapy.

METHODS AND MATERIALS

From 1981 through 1994, 51 previously irradiated patients with recurrent locally advanced colorectal cancer without evidence of distant metastatic disease were treated at Mayo Clinic Rochester with surgical resection and IOERT +/- additional EBRT. An attempt was made to achieve a gross total resection before IOERT if it could be safely accomplished. The median IOERT dose was 20 Gy (range, 10--30 Gy). Thirty-seven patients received additional EBRT either pre- or postoperatively with doses ranging from 5 to 50.4 Gy (median 25.2 Gy). Twenty patients received 5-fluorouracil +/- leucovorin during EBRT. Three patients received additional cycles of 5-fluorouracil +/- leucovorin as maintenance chemotherapy.

RESULTS

Thirty males and 21 females with a median age of 55 years (range 31--73 years) were treated. Thirty-four patients have died; the median follow-up in surviving patients is 21 months. The median, 2-yr, and 5-yr actuarial overall survivals are 23 months, 48% and 12%, respectively. The 2-yr actuarial central control (within IOERT field) is 72%. Local control at 2 years has been maintained in 60% of patients. There is a trend toward improved local control in patients who received > or =30 Gy EBRT in addition to IOERT as compared to those who received no EBRT or <30 Gy with 2-yr local control rates of 81% vs. 54%. Distant metastatic disease has developed in 25 patients, and the actuarial rate of distant progression at 2 and 4 years is 56% and 76%, respectively. Peripheral neuropathy was the main IOERT-related toxicity; 16 (32%) patients developed neuropathies (7 mild, 5 moderate, 4 severe). Ureteral narrowing or obstruction occurred in seven patients. All but one patient with neuropathy or ureter fibrosis received IOERT doses > or =20 Gy.

CONCLUSION

Long-term local control can be obtained in a substantial proportion of patients with aggressive combined modality therapy, but long-term survival is poor due to the high rate of distant metastasis. Re-irradiation with EBRT in addition to IOERT appears to improve local control. Strategies to improve survival in these poor-risk patients may include the more routine use of conventional systemic chemotherapy or the addition of novel systemic therapies.

Treatment of cholangiocarcinoma complicating primary sclerosing cholangitis: the Mayo Clinic experience

OBJECTIVES

The aims of this retrospective study were to assess the frequency with which we used different treatment modalities for patients with primary sclerosing cholangitis (PSC) and cholangiocellular carcinoma (CCA).

METHODS

A total of 41 patients with known CCA complicating PSC with a median age of 49 yr (range, 27-75 yr) were identified from a group of 1009 patients (4%) with PSC seen over 10 yr at the Mayo Clinic.

RESULTS

These patients received mainly five forms of treatment: 10 patients were treated with radiation therapy (RT) with or without 5-fluorouracil (5-FU) (seven with palliative and three with curative intent), nine with stent placement for cholestasis, 12 with conservative treatment, four with surgical resection (one of four received RT and 5-FU), and three patients with orthotopic liver transplantation and RT, with or without 5-FU. One patient was treated with 5-FU alone, one with photodynamic therapy, and one patient with somatostatin analog. A total of 36 patients died, whereas four (10%) patients survived (two with surgical resection, one with orthotopic liver transplantation and RT, and one with stent placement) during a median follow-up of 5.5 months (range, 1-75 months). One patient was lost to follow-up.

CONCLUSIONS

In highly selective cases, resective surgery seems to be of benefit in PSC patients with CCA. However, these therapies are rarely applied to these patients because of the advanced nature of the disease at the time of diagnosis. Efforts should be directed at earlier identification of potential surgical candidates.

Low-risk corpus cancer: is lymphadenectomy or radiotherapy necessary?

OBJECTIVE

The objective of this study was to find readily ascertainable intraoperative pathologic indicators that would discriminate a subgroup of early corpus cancers that would not require lymphadenectomy or adjuvant radiotherapy.

STUDY DESIGN

Between 1984 and 1993, a total of 328 patients with endometrioid corpus cancer, grade 1 or 2 tumor, myometrial invasion < or =50%, and no intraoperative evidence of macroscopic extrauterine spread were treated surgically. Pelvic lymphadenectomy was performed in 187 cases (57%), and nodes were positive in nine cases (5%). Adjuvant radiotherapy was administered to 65 patients (20%). Median follow-up was 88 months.

RESULTS

The 5-year overall cancer-related and recurrence-free survivals were 97% and 96%, respectively. Primary tumor diameter and lymphatic or vascular invasion significantly affected longevity. No patient with tumor diameter < or =2 cm had positive lymph nodes or died of disease.

CONCLUSION

Patients who have International Federation of Gynecology and Obstetrics grade 1 or 2 endometrioid corpus cancer with greatest surface dimension < or =2 cm, myometrial invasion < or =50%, and no intraoperative evidence of macroscopic disease can be treated optimally with hysterectomy only.

Treatment of extraprostatic cancer in clinically organ-confined prostate cancer by permanent interstitial brachytherapy: is extraprostatic seed placement necessary?

PURPOSE

Successful treatment with ultrasound-guided transperineal interstitial permanent prostate brachytherapy (TIPPB) relies on effective radiation coverage of intraprostatic and clinically occult extraprostatic cancer. This study examines prostatectomy findings as they relate to treatment of extraprostatic extension (EPE) of cancer and TIPPB techniques and dosimetry.

MATERIALS AND METHODS

A total of 313 prostatectomy specimens from patients with clinical tumor classification T1-T2b adenocarcinomas, serum prostate-specific antigen <20 ng/mL, and Gleason score <8 were whole mounted and evaluated for intraprostatic cancer volume and extraprostatic radial distance, area of perforation, and cancer density. From these data, extraprostatic cancer volume is calculated and used to estimate extraprostatic tumor control probabilities using the linear quadratic radiobiological model and Poisson statistics. TIPPB dose-gradient characteristics at the prostate periphery are examined.

RESULTS

Intraprostatic cancer volume ranges from 0 to 38 cc, whereas extraprostatic cancer volume ranges from 0 to 4.6 cc (mean 0.06 cc). The radial distance of EPE ranges from 0 to 4.4 mm (mean 0.18 mm). The ratio of extraprostatic to intraprostatic cancer volume ranges from 0% to 18% (mean 0.4%).

CONCLUSIONS

Only small amounts of clinically occult extraprostatic cancer were identified in the majority of specimens with EPE. Tumor control probability calculations suggest that this volume of cancer may be treated effectively with TIPPB. Treatment of this cancer possibly is achieved with an intraprostatic implant, but treatment of all cancers identified in this study suggests that some extraprostatic seed placement is desirable.

Prolonged disease-free survival after orthotopic liver transplantation plus adjuvant chemoirradiation for cholangiocarcinoma

Orthotopic liver transplantation (OLT) alone for unresectable cholangiocarcinoma is often associated with early disease relapse and limited survival. Because of these discouraging results, most programs have abandoned OLT for cholangiocarcinoma. However, a small percentage of patients have achieved prolonged survival after OLT, suggesting that adjuvant approaches could perhaps improve the survival outcome. Based on these concepts, a protocol was developed at the Mayo Clinic using preoperative irradiation and chemotherapy for patients with cholangiocarcinoma. We report our initial results with this pilot experience. Patients with unresectable cholangiocarcinoma above the cystic duct without intrahepatic or extrahepatic metastases were eligible. Patients initially received external-beam irradiation plus bolus fluorouracil (5-FU), followed by brachytherapy with iridium and concomitant protracted venous infusion of 5-FU. 5-FU was then administered continuously through an ambulatory infusion pump until OLT. After irradiation, patients underwent an exploratory laparotomy to exclude metastatic disease. To date, 19 patients have been enrolled onto the study and have been treated with irradiation. Eight patients did not go on to OLT because of the presence of metastasis at the time of exploratory laparotomy (n = 6), subsequent development of malignant ascites (n = 1), or death from intrahepatic biliary sepsis (n = 1). Eleven patients completed the protocol with successful OLT. Except for 1 patient, all had early-stage disease (stages I and II) in the explanted liver. All patients who underwent OLT are alive, 3 patients are at risk at 12 months or less, and the remaining 8 patients have a median follow-up of 44 months (range, 17 to 83 months; 7 of 9 patients > 36 months). Only 1 patient developed tumor relapse. OLT in combination with preoperative irradiation and chemotherapy is associated with prolonged disease-free and overall survival in highly selected patients with early-stage cholangiocarcinoma.

Results of irradiation or chemoirradiation following resection of gastric adenocarcinoma

PURPOSE

To evaluate the results of postoperative irradiation +/- chemotherapy for carcinoma of the stomach and gastroesophageal junction.

METHODS AND MATERIALS

The records of 63 patients who underwent resection for stomach cancer were retrospectively reviewed. Twenty-five patients had complete resection with no residual disease but with high-risk factors for relapse. Twenty-eight had microscopic residual and 10 had gross residual disease. Doses of irradiation ranged from 39.6 to 59.4 Gy with a median dose of 50.4 Gy in 1.8 Gy fractions. Fifty-three of the 63 (84%) patients received 5-fluorouracil (5-FU)-based chemotherapy.

RESULTS

The median duration of survival was 19.3 months for patients with no residual disease, 16.7 months for those with microscopic residual disease, and 9.2 months for those with gross residual disease (p = 0.01). The amount of residual disease also significantly impacted locoregional control (p = 0.04). Patients with linitis plastica did significantly worse in terms of survival, locoregional control, and distant control than those without linitis plastica. The use of 4 or more irradiation fields was associated with a significant decrease in the rate of Grade 4 or 5 toxicity when compared to the patients treated with 2 fields (p = 0.05).

CONCLUSIONS

There was a significant association between survival and extent of residual disease after resection as well as the presence of linitis plastica. Distant failures are common and effective systemic therapy will be necessary to improve outcome. The toxicity of combined modality treatment appears to be reduced by using greater than 2 irradiation fields.

Results of irradiation or chemoirradiation for primary unresectable, locally recurrent, or grossly incomplete resection of gastric adenocarcinoma

OBJECTIVE

To evaluate the results of irradiation +/- chemotherapy for patients with unresectable gastric carcinoma.

MATERIALS AND METHODS

The records of 60 patients with a gastric or gastroesophageal junction adenocarcinoma and a locally advanced unresectable primary (n = 28), a local or regional recurrence (n = 21), or gross residual disease following incomplete resection (n = 11) were retrospectively reviewed. Patients were treated with external beam irradiation (EBRT) alone or external beam plus intraoperative irradiation (IOERT), and 55 of the 60 (92%) patients received 5-FU based chemotherapy.

RESULTS

The median survival for the entire cohort was 11.6 months. There was no significant difference in median survival between each of the three treatment groups. In examining the extent of disease there was a significant difference in survival based on the number of sites involved. Nine patients with disease limited to a single non-nodal site appeared to represent a favorable subgroup compared to the rest of the patients (median survival of 21.8 months vs. 10.2 months,p = 0.03). In the patients with recurrent disease, the number of sites involved (p = 0.05), and total dose adding external beam dose to IOERT dose (> 54 Gy vs. < or =54 Gy, p = 0.06) were of borderline significance in regard to survival.

CONCLUSIONS

In patients with either primary unresectable, locally or regionally recurrent, or incompletely resected gastric carcinoma, the overall survival is similar, and related to the extent of disease based on the number of regional sites involved. The patients with a single non-nodal site of disease represent a favorable subgroup and patients with recurrent disease may benefit from total irradiation doses > 54 Gy.

Conformal irradiation for hepatobiliary malignancies

The term 'conformal irradiation' is usually used to describe the delivery of sophisticated high dose external beam irradiation (EBRT) with the aid of 3-D treatment planning and the option of both coplanar and non-coplanar beams. Data will be presented from the University of Michigan which suggest that conformal high dose EBRT (48-72.6 Gy) can be used for intrahepatic cancers, both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (IHCC), to potentially increase local control and survival over what would be expected with lower dose EBRT. For purpose of this discussion, the term conformal irradiation will be expanded to include other techniques which conform the high dose irradiation boost volume in close proximity to unresected tumor or positive margins of resection. Data will be presented from series which utilize transcatheter iridium and intraoperative electron irradiation (IOERT) supplements to EBRT +/- concomitant chemotherapy. Each method intensifies treatment in an attempt to improve local control and survival.

Future role of radiotherapy as a component of treatment in biliopancreatic cancers

For resected and unresectable pancreas cancers, data will be summarized from both adjuvant and locally unresectable pancreas cancer series (EBRT +/- IOERT) to demonstrate the justification of continuing to utilize chemo-irradiation as a component of treatment. The resultant improvements in local control with combined modality treatment, however, achieve only minimal improvements in survival in view of the high incidence of abdominal relapse (liver and peritoneal). Further improvement in survival may necessitate regional approaches for chemotherapy or may await advances in gene therapy. For locally unresectable and resected but residual bile duct malignancies, chemoirradiation appears to enhance tumor control and survival. Dose intensification of both modalities may be useful in improving disease control and survival. After chemoirradiation, the addition of liver transplant, in carefully selected patients who are unresectable with standard resection, may further enhance disease control and survival over what would be expected with either approach in isolation.

Intraoperative irradiation: current and future status

Intraoperative radiation therapy (IORT) in its broadest sense refers to the delivery of irradiation at the time of an operation. This article will discusses the rationale for and results of both intraoperative electron radiation therapy and intraoperative high dose rate brachytherapy when used in conjunction with surgical exploration and resection and external beam radiation therapy and chemotherapy. Both IORT methods evolved with similar philosophies as an attempt to achieve higher effective doses of irradiation while dose limiting structures are surgically displaced.

Radiation therapy for histologically confirmed primary central nervous system germinoma

PURPOSE

To evaluate survival and patterns of recurrence in patients with primary central nervous system germinoma treated with radiation therapy.

METHODS AND MATERIALS

Data regarding 48 patients with histologically confirmed, primary central nervous system germinoma were reviewed. All had been operated on at the Mayo Clinic between the years 1935 and 1993. Thirty-two patients (67%) were treated since 1973. The study group included 39 males and 9 females, with a median age at diagnosis of 17 years (range, 6-42 years). Twelve patients (25%) were treated with craniospinal axis irradiation, 11 (23%) received whole-brain irradiation without spinal axis irradiation, and 24 (50%) underwent partial-brain irradiation. Treatment volumes were unknown in one patient. The median dose to the primary tumor was 44.00 Gy (range, 7.44-59.40 Gy). The median follow-up was 5.5 years (range, 4 months to 37 years).

RESULTS

Actuarial 5-year and 10-year survival for the entire study group of patients was 80%. There was a trend toward improved survival in patients treated after 1973 (introduction of computed tomography) with 5-year and 10-year survival of 91% vs. 63% in prior years (p = 0.07). For the group of 31 patients treated since 1973 with known treatment volumes, the spinal axis failure rate at 5 years was 49% for patients treated with partial brain fields (11 patients) vs. 0% for those having undergone whole brain (10 patients) or craniospinal axis (10 patients) irradiation (p = 0.007). The rate of brain failure was also significantly higher in patients receiving less than whole-brain irradiation; at 5 years, 45% of the patients treated with partial-brain fields had intracranial recurrence of disease compared to 6 % of patients treated with craniospinal axis or whole-brain irradiation (p = 0.01). Among the 32 modern era patients, the rate of brain failure was higher in patients who received doses less than 40 Gy (median dose, 48.55 Gy; range, 30.60-59.40 Gy) to the primary tumor (5-year brain failure rate 52% vs. 11%, p = 0.002).

CONCLUSION

The long-term survival of patients with histologically proven CNS germinoma treated with radiation is excellent. Whole-brain or craniospinal axis irradiation appears to result in fewer spine and brain failures than does partial-brain irradiation. Furthermore, the administration of doses greater than 40 Gy to the primary tumor is associated with better local control.

Central neurocytomas

BACKGROUND

This analysis was performed to examine the outcome of patients with histologically confirmed central neurocytomas.

METHODS

Thirty-two patients with histologically confirmed central neurocytomas were evaluated retrospectively. Patients were treated with various combinations of surgery, chemotherapy, and radiotherapy (RT). Follow-up ranged from 2.3 to 15.3 years (median, 4.7 years).

RESULTS

The overall 5-year survival and local control rates were 81% and 79%, respectively. No patient developed metastases. The 5-year local control rate was 70% for patients undergoing subtotal resection (STR) and 100% for those undergoing gross total resection (GTR) (P = 0.08). The 5-year survival rate was 77% for patients undergoing STR and 90% for those undergoing GTR (P = 0.44). The effect of RT was evaluated for patients undergoing STR. The 5-year local control rate was 100% for patients who received RT after STR compared with 50% for those who did not (P = 0.02). The 5-year survival rate was 88% for patients who received RT after STR compared with 71% for those who did not (P = 0.3). Three patients received salvage RT for local progression after resection. All were alive and free of disease 1 to 6 years after RT.

CONCLUSIONS

GTR results in a very high likelihood of local control and survival. Postoperative RT appears to improve local control rates significantly for patients who have undergone STR. The overall prognosis of patients with central neurocytomas is quite favorable, with an actuarial 5-year survival rate of 81%.

A multiple prognostic index predictive of disease outcome after irradiation for clinically localized prostate carcinoma

BACKGROUND

This investigation was conducted to identify independent pretherapy disease-related factors associated with disease outcome in patients with clinically localized carcinoma of the prostate (CaP) and to develop models that incorporated relevant covariates for estimating the risk of disease relapse after irradiation (RT).

METHODS

The outcome of 500 patients treated only with RT between March 1987 and June 1993 for clinical Stages T1-4N0,XM0 CaP was evaluated. The risk of disease relapse as a function of individual prognostic variables, and combinations thereof, was determined using logistic regression.

RESULTS

With a median follow-up of 43 months (range, 4-103 months), 69 patients (14%) had clinical evidence of local recurrence (27 patients), regional lymph node relapse (4 patients), or metastatic relapse (38 patients) within 5 years of RT. Forty additional patients (8%) had biochemical relapse based solely on the post-RT serum prostate specific antigen (PSA) profile. Clinical tumor stage (P = 0.0006), Gleason score (P = 0.001) of the diagnostic biopsy specimen, and pretherapy PSA (P < 0.0001) were associated with disease relapse. The risk of any relapse within 5 years of RT was determined and graphically displayed as risk estimate plots for combinations of these pretherapy prognostic variables.

CONCLUSIONS

The combination of pretherapy clinical tumor (T) stage, Gleason score, and PSA level can be used to obtain improved estimates of the risk for disease relapse in patients treated solely with RT for clinically localized CaP. Risk estimate plots of this type may facilitate exchange of therapeutic outcome information, be instrumental in pretherapy decision-making for the new patient with this condition, and aid in the selection of patients for future studies.

The treatment of locally advanced colon cancer

PURPOSE

The results of therapy for 103 patients with locally advanced colon cancer who received radiotherapy were analyzed to determine the outcome and tolerance of therapy.

METHODS AND MATERIALS

Between 1974 and 1994, 103 patients received radiotherapy and maximal resection of locally advanced colon cancers. Following resection, 50 patients had no residual disease, 18 patients had microscopic residual disease, and 35 patients had gross residual disease. External beam radiotherapy was initiated 1 to 4 months following resection except in two patients who received preoperative radiotherapy. Treatment was delivered to the tumor bed and adjacent lymph nodes using 4 to 18 MV X-rays with doses ranging from 16.2 to 60 Gy. Intraoperative electron radiotherapy (IOERT) was also administered to 11 of the patients with doses ranging from 10 to 20 Gy. Chemotherapy was administered to 77 patients. Follow-up in survivors ranged from 0.5 to 17 years (median: 5.8 years).

RESULTS

The 5-year actuarial local failure rate was 10% for patients with no residual disease, 54% for patients with microscopic residual disease, and 79% for patients with gross residual disease (p < 0.0001). For patients with residual disease, local failure occurred in 11% of patients receiving IOERT compared with 82% of patients receiving only external beam therapy (p = 0.02). The 5-year actuarial survival rate was 66% for patients with no residual disease, 47% for patients with microscopic residual disease, and 23% for patients with gross residual disease (p = 0.0009). The 5-year survival rate in patients with residual disease was 76% for patients receiving IOERT and 26% for patients receiving external beam therapy alone (p = 0.04).

CONCLUSIONS

Patients with locally advanced colon cancer who have had a complete resection have a high probability of local control after external beam irradiation +/- 5 fluorouracil (5FU)-based systemic therapy. The toxicity of therapy can be minimized with attention to treatment technique and dose. Local control and survival rates in patients with residual disease who received IOERT appear to be significantly greater than for those patients who received external beam radiotherapy therapy alone.

Histologically confirmed pineal tumors and other germ cell tumors of the brain

BACKGROUND

This study examined the outcome of patients with histologically confirmed pineal region tumors.

METHODS

One hundred thirty-five patients with histologically confirmed pineal tumors and other germ cell tumors of the brain were evaluated retrospectively. The pineal parenchymal tumors (PPTs) included 15 pineoblastomas (PB), 2 mixed PPTs, 4 PPTs with intermediate differentiation, and 9 pineocytomas. The germ cell tumors included 48 germinomas, 26 mixed germ cell tumors, 11 mature teratomas, 9 immature teratomas, 6 malignant teratomas, 2 yolk sac tumors, and 3 choriocarcinomas. Patients were treated with various combinations of chemotherapy, radiotherapy, and surgery. The duration of follow-up ranged from 0.25 to 37.3 years, with a median follow-up of 5.3 years.

RESULTS

The 5-year patient survival rate was 86% for those with mature teratomas; 86% with pineocytomas; 80% with germinomas; 67% with immature teratomas; 49% with PPTs, excluding pineocytomas; 38% with mixed germ cell tumors; and 17% with other germ cell histologies (P = 0.0001). The delivery of > 44 Gray (Gy) to germinomas and > 50 Gy to PPTs and nongerminomatous germ cell tumors (NGGCTs) other than mature and immature teratomas was associated with improved survival. A greater extent of resection was associated with a higher rate of survival in all patients with NGGCTs. The administration of chemotherapy was associated with improved survival in those patients with NGGCTs other than mature and immature teratomas.

CONCLUSIONS

Prognosis was dependent on tumor type. Obtaining a tissue diagnosis made it possible to tailor therapy according to tumor type and potentially improve the survival of patients. Survival was dependent on the dose of radiation administered to patients with PPTs, germinomas, and NGGCTs other than mature and immature teratomas. More extensive resection and the use of chemotherapy were also associated with improved survival in subgroups of patients with NGGCTs. Treatment recommendations are described in detail in the article.

Nongerminomatous germ cell tumors of the brain

PURPOSE

This analysis was performed to determine the clinical outcome of patients with primary nongerminomatous germ cell tumors of the brain. The efficacy of various treatment options was evaluated.

METHODS AND MATERIALS

A total of 57 patients with primary nongerminomatous germ cell tumors of the brain were identified. Patient-related data were collected and analyzed retrospectively. Follow-up in surviving patients ranged from 3 to 243 months (median follow-up 36). Survival and failure rates were determined using the Kaplan-Meier method, and differences between the survival curves were evaluated using either the log rank test or the Wilcoxon test.

RESULTS

The 3-year survival rate was 86% for patients with mature teratomas, 67% for patients with immature teratomas, 44% for patients with mixed germ cell tumors, and 13% for patients with the other histologic types (p = 0.02). The 3-year survival rate was 0% for patients having biopsies alone, 32% for patients having subtotal resections, and 73% for patients having gross total resections (p = 0.0001). Patients with tumors other than mature or immature teratomas were evaluated for possible relationships between the administration of chemotherapy or radiotherapy and survival. Patients who received chemotherapy had a 3-year survival rate of 56% compared to 8% for those patients who did not receive chemotherapy (p = 0.0001) Patients who received radiotherapy had a 3-year survival rate of 46% compared to 11% for those patients who did not receive radiotherapy (p = 0.0015).

CONCLUSION

The survival of patients with primary nongerminomatous germ cell tumors of the brain is dependent on tumor histology and the extent of surgical resection. Patients with tumors other than mature or immature teratomas appear to benefit from the administration of chemotherapy and radiotherapy.

Indications for and results of irradiation +/- chemotherapy for rectal cancer

With mobile rectal cancers, surgery alone is insufficient treatment for most patients with high-risk factors of tumour extension beyond the rectal wall, node involvement, or both in conjunction. While single modality adjuvant treatment with pre- or postoperative irradiation can reduce the incidence of local relapse, a statistically significant impact on survival has not been achieved. Combined modality postoperative chemoirradiation has resulted in both improved disease control (local and distant) and improved survival (disease free and overall). Randomized trials are underway in high-risk patients to determine the most optimal combinations of postoperative chemoirradiation and to compare preoperative versus postoperative chemoirradiation. Standard therapy with surgery, external irradiation, and chemotherapy is often unsuccessful for patients with locally advanced primary cancers that are unresectable for cure or locally recurrent cancers. When intraoperative electron irradiation is combined with standard treatment, encouraging trends are seen with regard to improvements in local control and survival in separate analyses from the Mayo Clinic and the Massachusetts General Hospital. More standard use of systemic therapy is needed as a component of treatment, however, in view of high rates of systemic failure in spite of the locally aggressive treatment regimens.

Assessing the interaction of irradiation with etoposide or idarubicin

OBJECTIVE

To compare the interactions of two topoisomerase II inhibitors, etoposide and idarubicin, with irradiation.

DESIGN

Two mathematical modeling systems were used to assess the interactions.

METHODS AND RESULTS

Hamster lung fibroblast cells (V79) were exposed to etoposide or idarubicin for 24 hours before or immediately after irradiation. Post radiation treatment with etoposide or idarubicin resulted in radiosensitization, as demonstrated by a decrease in the mean inactivation dose. Exposure to either drug before irradiation resulted in no radiosensitization. The first mathematical modeling system used was isobologram analysis. This analysis revealed a synergistic interaction if etoposide exposure followed irradiation. The interaction from the combination of irradiation and preradiation etoposide was within the envelope of addivity. Irradiation and postradiation idarubicin exposure also resulted in an interaction within the envelope of addivity, whereas preradiation idarubicin exposure resulted in a slightly less than additive interaction. Next, analyses were performed by the median effect principle. Synergistic interactions were demonstrated for combinations of etoposide and irradiation as well as idarubicin and irradiation. Synergistic interactions were more likely when drug exposure (either idarubicin or etoposide) followed irradiation. Experiments at various ratios of radiation dose to drug concentration showed that the likelihood of a synergistic interaction increased as the drug concentration increased relative to the radiation dose.

CONCLUSION

The interaction of irradiation with topoisomerase II-reactive agents should be further explored in human tumor cell lines.

Etoposide-resistance in the multidrug-resistant LZ-8 cells

The multidrug-resistant LZ-8 cells were found to exhibit marked resistance to etoposide compared to wild-type, parental V79 cells. The multidrug resistant phenotype did not significantly contribute to this etoposide-resistance. Following exposure of LZ-8 cells and V79 cells to equivalent concentrations of etoposide, there was a dramatic reduction in the number of etoposide-induced stabilized DNA-topoisomerase II complexes in the LZ-8 cells compared to V79 cells, however, this reduction was not found when nuclei isolated from LZ-8 and V79 cells were exposed to equivalent concentrations of etoposide. These results suggest that cytoplasmic factors are involved in the etoposide-resistance of LZ-8 cells.