ASCO 12 Annual Meeting, June 1-5, 2012, Chicago, Illinois, USA
Androgen deprivation therapy (ADT) use in Medicare beneficiaries with nonmetastatic (M0) prostate
cancer (PC) in the United States.
Abstract No:e15169
Citation:
J Clin Oncol 30, 2012 (suppl; abstr e15169)
Publication-only abstracts (abstract number preceded by an "e"), published in conjunction with
the 2012 Annual Meeting but not presented at the Meeting, can be found online only.
The publication-only abstracts are not included in the print or USB versions of the ASCO Annual
Meeting Proceedings Part I, but they are citable to the Journal of Clinical Oncology as a
supplement (see citation on left).
Author(s): Thomas J. Arneson, Karynsa Cetin, Scott Stryker, Alexander Liede, Tom Murray, Shuling Li, Anne
Hudson Blaes; Chronic Disease Research Group, Minneapolis, MN; Center for Observational Research,
Amgen Inc, Thousand Oaks, CA; University of Minnesota, Minneapolis, MN
Abstract:
Background: ADT is well-established for metastatic PC but is also used in men with less advanced PC.
Patterns of ADT use in the M0 PC setting have not been well-described. Methods: Medicare claims in 2005
for men aged ≥66 years (yrs) were assessed for use of gonadotropin-releasing hormone agonists or bilateral
orchiectomy. The cohort was limited to men who, during the 15 months (mos) prior to their first 2005 ADT
claim, had continuous Parts A + B coverage, a diagnosis code for PC, no claims for metastases (except
lymph nodes), and no claims for ADT. Follow-up (f/u) was from ADT initiation to 3 yrs, death, or change in
Medicare coverage. Regimen duration was defined by combining claim service count and dosage with FDA
label dosing. Because ADT has biologic activity beyond the recommended regimen duration, active dose
time was calculated by adding 3 and 6 mos to claims for regimens <6 mos and ≥6 mos, respectively.
Interruption was defined as ≥180 days from end of active dose time to next ADT claim. Results: We
identified 3246 M0 PC patients aged ≥66 yrs who initiated ADT in 2005 but describe results in the 2161 who
had 3 full yrs of f/u (data for the entire cohort were similar). Nearly 70% received only 1 type of ADT agent
during f/u (25% had 2 types, 5% had 3 or 4 types), and 73% started on a 3-or 4-month regimen. The
distribution of patients by first ADT type (and by type received at any point) was: leuprolide injection: 54%
(67%); goserelin implant: 36% (43%); Triptorelin injection: 6% (19%); leuprolide implant: 2% (4%);
orchiectomy: <1% (1%); and histrelin implant: 0% (3%). Use of >1 type of ADT agent was more common in
men who began with goserelin (45%) or Triptorelin (53%) versus leuprolide (≤24%). At three years after
ADT initiation, 36% received ADT for the entire 36-month period, 15% for 24-35 mos, 17% for 12-23 mos,
and 32% for <12 mos. Interruption in active therapy occurred in only 13%. Conclusions: Most elderly men
with M0 PC initiating ADT in 2005 started on a 3- or 4-month leuprolide or goserelin regimen. Though these
agents remained the most commonly used throughout f/u, switching was common (30% used >1 type during
f/u). ADT was continued for at least 2 yrs in nearly half and extended to 3 yrs in over one-third of the cohort.
Utilization of bone densitometry and administration of bisphosphonates to prevent osteoporosis in
patients with nonmetastatic prostate cancer receiving anti-androgen therapy.
Abstract No:6099
Citation:
J Clin Oncol 30, 2012 (suppl; abstr 6099)
Author(s): Muhammad Atif Khan, Abby E Holt, Swetha Gujja, Rangaswamy Govindarajan; University of
Arkansas for Medical Sciences Hospital, Little Rock, AR; Arkansas Department of Health, Little Rock, AR;
University of Arkansas for Medical Sciences, Little Rock, AR
Abstract:
Background: Prostate cancer subjects with PSA relapse who are treated with androgen deprivation therapy
(ADT) are recommended to have baseline and serial bone densitometry (BD) and receive intravenous
bisphsphonates (BP). Utilization of BD and BP therapy was evaluated in a retrospective SEER Medicare
database analysis. Methods: A cohort study of men aged aged ≥ 65 years with a nonmetastatic incident
diagnosis of prostate cancer between 2004 and 2008 was conducted. Data were obtained from the
Surveillance, Epidemiology and End Results (SEER) linked Medicare claims. Medicare claims were used to
select prostate cancer cases who had ever received ADT and intravenous BP as part of their treatment. ADT
was defined as an orchiectomy, goserelin, leuprolide, leuprolide implant, or Triptorelin. BD and treatment
with pamidronate or zoledronic acid were identified using Medicare HCPCS codes. One-sided exact binomial
test of proportion was used to determine if the physician compliance rate is consistent with 80%; meaning
equal to or higher than 80%. Results: 157,974 newly diagnosed prostate cancer cases were identified. Of
those, 100,865 were age 65 and above and had no bone metastases. Subjects who did not have ADT claims
were excluded. 30,846 patients were eligible for analysis. Cases were further stratified by use of BD and BP
therapy. Results revealed 86.8% (N=26,774) on ADT did not receive either a BD or intravenous BP therapy.
Approximately 2.9% (N=885) of the cases on ADT received BP treatment without ever receiving a BD. 9.3%
(N=2,863) of the cases on ADT received a BD without receiving intravenous BP, while only 1.05% (N=324)
of the cases on ADT received both a BD and BP. A compliance rate of 1.05%, those patients receiving both
bone densitometries to screen for bone loss and preventive therapy, was well below the expected rate of
80%. Conclusions: Contrary to the recommendations, BD assessment and BP use is under utilized in men
receiving ADT for non metastatic prostate cancer. Education of practicing physicians regarding better
screening and preventative measures for osteoporosis in this population is warranted.