Validating a Claims-based Method for Assessing Severe Rectal and Urinary Adverse Effects of Radiotherapy

Incidence of genitourinary complications following radiation therapy for localised prostate cancer

Purpose

Studies of genitourinary toxicity following radiotherapy for prostate cancer are mainly from high volume single institutions and the incidence and burden of treatment remain uncertain. Hence we determine the cumulative incidence of treatment-related genitourinary toxicity in patients with localised prostate cancer treated with primary external beam radiotherapy (EBRT) at a state population level.

Methods

We analysed data from a prospective population-based cohort, including hospital admission and cancer registry data, for men with localised prostate cancer who underwent primary EBRT without nodal irradiation between 1998 and 2019 in South Australia. The 10-year cumulative incidence of genitourinary toxicity requiring hospitalisation or procedures was determined. Clinical predictors of toxicity and the volume of admissions, non-operative, minor operative and major operative procedures were determined.

Results

All the included patients (n = 3350) had EBRT, with a median (IQR) of 74 Gy (70–78) in 37 fractions (35–39). The 10-year cumulative incidence of was 28.4% (95% CI 26.3–30.6) with a total of 2545 hospital admissions, including 1040 (41%) emergency and 1893 (74%) readmissions. The 10-year cumulative incidence of patients in this cohort requiring a urological operative procedure was 18% (95% CI 16.1–19.9), with a total of 106 (4.2%) non-operative, 1044 (41%) minor operative and 57 (2.2%) major operative urological procedures.

Conclusions

Genitourinary toxicity after radiotherapy for prostate cancer is common. Although there continue to be advancements in radiotherapy techniques, patients and physicians should be aware of the risk of late toxicity when considering EBRT.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-04124-x.

Urologic Complications Requiring Intervention Following High-dose Pelvic Radiation for Cervical Cancer

OBJECTIVE

To identify the incidence of radiation-induced urologic complication requiring procedural intervention following high-dose radiotherapy for cervical carcinoma, and to identify predictors of complication occurrence.

MATERIALS AND METHODS

We performed a retrospective chart review of cervical cancer patients undergoing radiotherapy with primary focus on procedural complications (Clavien-Dindo ≥ III). Clinical data were collected including radiation dose, procedure performed, timing of complication, and need for additional procedures. Univariate and multivariate logistic regression modeling was performed to assess predictive value of demographic and clinical variables.

RESULTS

A total of 126 patients with FIGO stage 1A2-4B cervical cancer were included in study analysis, with 18 patients experiencing procedural complication (14.3%). A total of 22 complications were identified, representing an average of 1.2 complications per patient with complication. The most common complications were ureteral stricture and radiation cystitis. The most common nononcologic procedures performed in the treatment of these complications were ureteral stenting, percutaneous nephrostomy tube placement, and cystoscopy. Notably, a total of 259 procedures were performed in the treatment of urologic complications, representing 14.4 procedures per patient and 24.6 procedures per patient with ureteral stricture. Logistic regression demonstrated active smoking at the time of diagnosis to be a predictor of procedural complication.

CONCLUSION

Radiotherapy in the treatment of cervical cancer is associated with a high rate of urologic procedural complication. These complications often require numerous procedures and long-term management given their complexity. These findings suggest a need for awareness and plans for multidisciplinary management of urologic complications in this patient population.

Costs and Complications After a Diagnosis of Prostate Cancer Treated With Time-Efficient Modalities: An Analysis of National Medicare Data

PURPOSE

Recent trends in payer and patient preferences increasingly incentivize time-efficient (≤2-week treatment time) prostate cancer treatments.

METHODS AND MATERIALS

National Medicare claims from January 1, 2011, through December 31, 2014, were analyzed to identify newly diagnosed prostate cancers. Three "radical treatment" cohorts were identified (prostatectomy, brachytherapy, and stereotactic body radiation therapy [SBRT]) and matched to an active surveillance (AS) cohort by using inverse probability treatment weighting via propensity score. Total costs at 1 year after biopsy were calculated for each cohort, and treatment-specific costs were estimated by subtracting total 1-year costs in each radical treatment group from those in the AS group.

RESULTS

Mean 1-year adjusted costs were highest among patients receiving SBRT ($26,895), lower for prostatectomy ($23,632), and lowest for brachytherapy ($19,980), whereas those for AS were $9687. Costs of radical modalities varied significantly by region, with the Mid-Atlantic and New England regions having the highest cost ranges (>$10,000) and the West South Central and Mountain regions the lowest range in costs (<$2000). Quantification of toxic effects showed that prostatectomy was associated with higher genitourinary incontinence (hazard ratio [HR] = 10.8 compared with AS) and sexual dysfunction (HR = 3.5), whereas the radiation modalities were associated with higher genitourinary irritation/bleeding (brachytherapy HR = 1.7; SBRT HR = 1.5) and gastrointestinal ulcer/stricture/fistula (brachytherapy HR = 2.7; SBRT HR = 3.0). Overall mean toxicity costs were highest among patients treated with prostatectomy ($3500) followed by brachytherapy ($1847), SBRT ($1327), and AS ($1303).

CONCLUSIONS

Time-efficient treatment techniques exhibit substantial variability in toxicity and costs. Furthermore, geographic location substantially influenced treatment costs.

Preservation of the mesureter to reduce urinary complications: analysis of data from the observational Leipzig School MMR study

OBJECTIVE

To evaluate the feasibility and effect of mesureteral preservation on urinary complications in the context of total mesometrial resection (TMMR), a surgical treatment for cervical cancer.

DESIGN

Retrospective cohort study with historic control.

SETTING

Single tertiary academic centre.

POPULATION

Women older than 18 with primary cervical cancer staged FIGO IB1-IIB enrolled in the prospective Leipzig School MMR study and underwent total mesometrial resection (TMMR) without adjuvant radiation.

METHOD

We retrospectively analysed 100 consecutive TMMR procedures which were performed for cancer of the uterine cervix and in which the mesureter was preserved (intervention group, 01/2014-06/2017). We compared this group with the previous 100 consecutive TMMRs, which were performed before the introduction of mesureteral preservation (control group, 09/2010-01/2014).

MAIN OUTCOME MEASURES

The occurrence of urological and specifically ureteral complications.

RESULTS

Mesureteral preservation was feasible and was associated with a significant decrease in ureteral complications (11% without mesureteral preservation versus 3% with mesureteral preservation, P = 0.049). Furthermore, we found a significant decrease in the number of postoperative percutaneous nephrostomies and re-operations (7% versus none, P = 0.014). There was also a trend towards a decrease in other urinary complications such as postoperative bladder atony and uretero-vaginal fistulas.

CONCLUSION

The mesureter constitutes a convenient dissection plane enabling the preservation of lateral ureteral blood supply during TMMR. In our study, maintenance of mesureteral integrity was associated with a significant reduction in ureteral complications. Mesureteral preservation might also be useful in other types of pelvic surgeries that carry a high risk of ureteral damage.

TWEETABLE ABSTRACT

Surgical preservation of the mesureter in cervical cancer patients was associated with a reduction in urinary complications.

US Geographical Variation in Rates of Shoulder and Knee Arthroscopy and Association With Orthopedist Density

IMPORTANCE

Although rates of arthroscopy have substantially increased, recent data question its comparative effectiveness.

OBJECTIVES

To assess time trends and geographical variations among several US states in arthroscopy rates and to assess the association of orthopedist density with arthroscopy rates.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, procedure rates were calculated for knee arthroscopy, shoulder arthroscopy, and arthroscopic rotator cuff repair using data from the State Ambulatory Surgery and Services Databases for 2006 to 2016 (as available) for the states of California, Colorado, Florida, Iowa, Kentucky, Maryland, Maine, Michigan, Minnesota, North Carolina, Nebraska, New Jersey, Nevada, New York, Oregon, Utah, Vermont, and Wisconsin. Data were analyzed from June 2017 to October 2019.

MAIN OUTCOMES AND MEASURES

Rates of knee arthroscopy, shoulder arthroscopy, and arthroscopic rotator cuff repair.

RESULTS

The combined data sets included 4 856 385 records with 2 530 840 female patients (47%); mean (SD) patient age was 49.13 (16.34) years. Rates per 100 000 persons showed large geographical variations for knee arthroscopy (from 63.31 [95% CI, 5.92-198.95] to 721.72 [95% CI, 633.41-806.20]), shoulder arthroscopy (from 53.02 [95% CI, 2.80-164.36] to 438.25 [95% CI, 399.00-476.78]), and arthroscopic rotator cuff repair (from 11.94 [95% CI, 1.30-56.98] to 185.35 [95% CI, 143.84-226.20]) across US states and years. There were significant downward time trends in knee arthroscopy rates in California, Florida, Iowa, Maryland, Michigan, Nebraska, and New Jersey and upward trends for arthroscopic rotator cuff repair in Colorado, Florida, Kentucky, Maine, and North Carolina. Orthopedist density was not associated with knee arthroscopy rates (slope = 3.07; 95% CI, -9.88 to 16.03; P = .54), shoulder arthroscopy rates (slope = 2.74; 95% CI, -6.53 to 12.01; P = .47), or rates of arthroscopic rotator cuff repair (slope = 1.15; 95% CI, -2.77 to 5.05; P = .49).

CONCLUSIONS AND RELEVANCE

There is large geographical variation in arthroscopy rates despite the questionable comparative effectiveness of these procedures. The reasons for increasing rates of rotator cuff surgery should be further examined.

Determining the Time of Cancer Recurrence Using Claims or Electronic Medical Record Data

PURPOSE

Data from claims and electronic medical records (EMRs) are frequently used to identify clinical events (eg, cancer diagnosis, stroke). However, accurately determining the time of clinical events can be challenging, and the methods used to generate time estimates are underdeveloped. We sought to develop an approach to determine the time of a clinical event-cancer recurrence-using high-dimensional longitudinal structured data.

METHODS

Manual chart abstraction provided information regarding the actual time of cancer recurrence. These data were linked to claims from Medicare or structured EMR data from the Cancer Research Network, which were used to determine time of recurrence for patients with lung or colorectal cancer. We analyzed the longitudinal profile of codes that could help determine the time of recurrence, adjusted for systematic differences between code dates and recurrence dates, and integrated time estimates from different codes to empirically derive an optimal algorithm.

RESULTS

We identified twelve code groups that could help determine the time of recurrence. Using claims data for patients with lung cancer, the optimal algorithm consisted of three code groups and provided an average prediction error of 4.8 months. Using EMR data or applying this approach to patients with colorectal cancer yielded similar results.

CONCLUSION

Time estimates were improved by selecting codes not necessarily the same as those used to identify recurrence, combining time estimates from multiple code groups, and adjusting for systematic bias between code dates and recurrence dates. Improving the accuracy of time estimates for clinical events can facilitate research, quality measurement, and process improvement.

Comparative Toxicities and Cost of Intensity-Modulated Radiotherapy, Proton Radiation, and Stereotactic Body Radiotherapy Among Younger Men With Prostate Cancer

Purpose To compare the toxicities and cost of proton radiation and stereotactic body radiotherapy (SBRT) with intensity-modulated radiotherapy (IMRT) for prostate cancer among men younger than 65 years of age with private insurance. Methods Using the MarketScan Commercial Claims and Encounters database, we identified men who received radiation for prostate cancer between 2008 and 2015. Patients undergoing proton therapy and SBRT were propensity score-matched to IMRT patients on the basis of clinical and sociodemographic factors. Proportional hazards models compared the cumulative incidence of urinary, bowel, and erectile dysfunction toxicities by treatment. Cost from a payer's perspective was calculated from claims and adjusted to 2015 dollars. Results A total of 693 proton therapy patients were matched to 3,465 IMRT patients. Proton therapy patients had a lower risk of composite urinary toxicity (33% v 42% at 2 years; P < .001) and erectile dysfunction (21% v 28% at 2 years; P < .001), but a higher risk of bowel toxicity (20% v 15% at 2 years; P = .02). Mean radiation cost was $115,501 for proton therapy patients and $59,012 for IMRT patients ( P < .001). A total of 310 SBRT patients were matched to 3,100 IMRT patients. There were no significant differences in composite urinary, bowel, or erectile dysfunction toxicities between SBRT and IMRT patients ( P > .05), although a higher risk of urinary fistula was noted with SBRT (1% v 0.1% at 2 years; P = .009). Mean radiation cost for SBRT was $49,504 and $57,244 for IMRT ( P < .001). Conclusion Among younger men with prostate cancer, proton radiation was associated with significant reductions in urinary toxicity but increased bowel toxicity at nearly twice the cost of IMRT. SBRT and IMRT were associated with similar toxicity profiles; SBRT was modestly less expensive than IMRT.

The burden of chronic ureteral stenting in cervical cancer survivors

PURPOSE

Ureteral obstruction in cervical cancer occurs in up to 11% of patients, many of whom undergo ureteral stenting. Our aim was to describe the patient burden of chronic ureteral stenting in a population-based cohort by detailing two objectives: (1) the frequency of repeat procedures for ureteral obstruction; and, (2) the frequency of urinary adverse effects (UAEs) (e.g., lower urinary tract symptoms, flank pain).

MATERIALS AND METHODS

From SEER-Medicare, we identified 202 women who underwent ureteral stent placement prior to or following cervical cancer treatment. The frequency of repeat procedures and rate ratios were compared between treatment modalities. The rates and rate ratios of UAEs were compared between our primary cohort (stent + cervical cancer) and the following groups: no stent + cervical cancer, stent + no cancer, and no stent + no cancer. The "no cancer" group was drawn from the 5% Medicare sample.

RESULTS

117/202 women (58%) underwent >1 stent procedure. The frequency of additional procedures was significantly higher in patients who received radiation as part of their treatment. UAEs were very common in women with stent + cancer. The rate of UTI was 190 (per 100 person-years), 67 for LUTS, 42 for stones, and 6 for flank pain. These rates were 3-10 fold higher than in the no stent + no cancer control group; rates were also higher than in the no stent + cancer and the stent + no cancer women.

CONCLUSIONS

The burden of disease associated with ureteral stents is higher than expected and urologists should be actively involved in stent management, screening for associated symptoms and offering definitive reconstruction when appropriate.

A review of routinely collected data studies in urology: Methodological considerations, reporting quality, and future directions

Studies using routinely collected data (RCD) are common in the urological literature; however, there are important considerations in the creation and review of RCD discoveries. A recent reporting guideline (REporting of studies Conducted using Observational Routinely-collected health Data, RECORD) was developed to improve the reporting of these studies. This narrative review examines important considerations for RCD studies. To assess the current level of reporting in the urological literature, we reviewed all the original research articles published in Journal of Urology and European Urology in 2014, and determined the proportion of the RECORD checklist items that were reported for RCD studies. There were 56 RCD studies identified among the 608 articles. When the RECORD items were considered applicable to the specific study, they were reported in 52.5% of cases. Studies most consistently (>80% of them) reported the names of the data sources, the study time frame, the extent to which the authors could access the database source, the patient selection, and discussed missing data. Few studies (<25%) discussed validation of key coding elements, details on data-linkage, data-cleaning, the impact of changing eligibility over time, or provided the complete list of coding elements used to define key study variables. Reporting factors specifically relevant in RCD studies may serve to increase the quality of these studies in the urological literature. With increased technological integration in healthcare and the proliferation of electronic medical records, RCD will continue to be an important source for urological research.

Propensity-Weighted Comparison of Long-Term Risk of Urinary Adverse Events in Elderly Women Treated For Cervical Cancer

PURPOSE

Cervical cancer treatment is associated with a risk of urinary adverse events (UAEs) such as ureteral stricture and vesicovaginal fistula. We sought to measure the long-term UAE risk after surgery and radiation therapy (RT), with confounding controlled through propensity-weighted models.

METHODS AND MATERIALS

From the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we identified women ≥66 years old with nonmetastatic cervical cancer treated with simple surgery (SS), radical hysterectomy (RH), external beam RT plus brachytherapy (EBRT+BT), or RT+surgery. We matched them to noncancer controls 1:3. Differences in demographic and cancer characteristics were balanced by propensity weighting. Grade 3 to 4 UAEs were identified by diagnosis codes plus treatment codes. Cumulative incidence was measured using Kaplan-Meier methods. The hazard associated with different cancer treatments was compared using Cox models.

RESULTS

UAEs occurred in 272 of 1808 cases (17%) and 222 of 5424 (4%) controls; most (62%) were ureteral strictures. The raw cumulative incidence of UAEs was highest in advanced cancers. UAEs occurred in 31% of patients after EBRT+BT, 25% of patients after RT+surgery, and 15% of patients after RH; however, after propensity weighting, the incidence was similar. In adjusted Cox models (reference = controls), the UAE risk was highest after RT+surgery (hazard ratio [HR], 5.07; 95% confidence interval [CI], 2.32-11.07), followed by EBRT+BT (HR, 3.33; 95% CI, 1.45-7.65), RH (HR, 3.65; 95% CI, 1.41-9.46) and SS (HR, 0.99; 95% CI, 0.32-3.01). The higher risk after RT+surgery versus EBRT+BT was statistically significant, whereas, EBRT+BT and RH were not significantly different from each other.

CONCLUSIONS

UAEs are common after cervical cancer treatment, particularly in patients with advanced cancers. UAEs are more common after RT, but these women tend to have the advanced cancers. After propensity weighting, the risk after RT was similar to that after surgery.

Propensity-weighted long-term risk of urinary adverse events after prostate cancer surgery, radiation, or both

BACKGROUND

Prostate cancer is the second most common cancer in men and has high survivorship, yet little is known about the long-term risk of urinary adverse events (UAEs) after treatment.

OBJECTIVE

To compare the long-term UAE incidence across treatment and control groups.

DESIGN, SETTING, AND PARTICIPANTS

Using a matched-cohort design, we identified elderly men treated with external-beam radiotherapy (EBRT; n=44 318), brachytherapy (BT; n=14 259), EBRT+BT (n=11 835), radical prostatectomy (RP; n=26 970), RP+EBRT (n=1557), or cryotherapy (n=2115) for non-metastatic prostate cancer and 144 816 non-cancer control individuals from the population-based Surveillance, Epidemiology, and End Results-Medicare linked data from 1992-2007 with follow-up through 2009.

OUTCOME MEASURES AND STATISTICAL ANALYSIS

The incidence of treated UAEs and time from cancer treatment to first UAE were analyzed in terms of propensity-weighted survival.

RESULTS

Median follow-up was 4.14 yr. At 10 yr, all treatment groups experienced higher propensity-weighted cumulative UAE incidence than the control group (16.1%; hazard risk [HR] 1.0), with the highest incidence for RP+EBRT (37.8%; HR 3.19, 95% confidence interval [CI] 2.79-3.66), followed by BT+EBRT (28.4%; HR 1.97, CI 1.85-2.10), RP (26.6%; HR 2.44, CI 2.34-2.55), cryotherapy (23.4%; HR 1.56, CI 1.30-1.87), BT (19.8%; HR 1.43, CI 1.33-1.53), and EBRT (19.7%; HR 1.11, CI 1.07-1.16). Bladder outlet obstruction was the most common event.

CONCLUSIONS

Men undergoing RP, RP+EBRT, and BT+EBRT experienced the highest UAE risk at 10 yr, although UAEs accrued differently over extended follow-up. The significant background UAE rate among non-cancer control individuals yields a risk attributable to prostate cancer treatment that is 17% lower than prior estimates.

PATIENT SUMMARY

We show that treatment for prostate cancer, especially combinations of two treatments such as radiation and surgery, carries a significant risk of urinary adverse events such as urethral stricture. This risk increases with time since treatment, emphasizing that treatments have long-term effects.

An algorithm to identify the development of lymphedema after breast cancer treatment

PURPOSE

Large, population-based studies are needed to better understand lymphedema, a major source of morbidity among breast cancer survivors. One challenge is identifying lymphedema in a consistent fashion. We sought to develop and validate an algorithm using Medicare claims to identify lymphedema after breast cancer surgery.

METHODS

From a population-based cohort of 2,597 elderly (65+) women who underwent incident breast cancer surgery in 2003 and completed annual telephone surveys through 2008, two algorithms were developed using Medicare claims from half of the cohort and validated in the remaining half. A lymphedema-positive case was defined by patient report.

RESULTS

A simple two ICD-9 code algorithm had 69 % sensitivity, 96 % specificity, positive predictive value >75 % if prevalence of lymphedema is >16 %, negative predictive value >90 %, and area under receiver operating characteristic curve (AUC) of 0.82 (95 % CI 0.80-0.85). A more sophisticated, multi-step algorithm utilizing diagnostic and treatment codes, logistic regression methods, and a reclassification step performed similarly to the two-code algorithm.

CONCLUSIONS

Given the similar performance of the two validated algorithms, the ease of implementing the simple algorithm and the fact that the simple algorithm does not include treatment codes, we recommend that this two-code algorithm be validated in and applied to other population-based breast cancer cohorts.

IMPLICATIONS FOR CANCER SURVIVORS

This validated lymphedema algorithm will facilitate the conduct of large, population-based studies in key areas (incidence rates, risk factors, prevention measures, treatment, and cost/economic analyses) that are critical to advancing our understanding and management of this challenging and debilitating chronic disease.