Fortbildungen / Formations continues 2012 - IUMSP

Clinical Trials
IBCSG 35-07 / SOLE
SOLE (Study Of Letrozole Extension), a worldwide trial
coordinated by the International Breast Cancer Study
Group (IBCSG), is designed to compare extended continuous
letrozole for 5 years with intermittent letrozole
over a 5-year period for postmenopausal women who are
disease-free following 4 to 6 years of prior adjuvant endocrine
therapy with SERM(s) and/or AI(s) for endocrineresponsive,
node-positive, operable breast cancer.
In March the trial reached the accrual of 4000 patients or
80% of the planned sample size of 4800. With the continuously
high accrual rate we expect that the trial will close
to accrual in the third quarter of this year. All participating
sites have been informed to restrict the information of
new potential participants to patients which can be randomized
before fall 2012.
IBCSG 38-09/ BIG 3-07/ TROG DCIS
This randomized phase III study of radiation doses and
fractionation schedules for ductal carcinoma in situ (DCIS)
of the breast is conducted by IBCSG in Switzerland and
Italy on behalf of the Trans Tasman Radiation Oncology
Group TROG. Women with completely excised non-low
risk ductal carcinoma in situ (DCIS) treated by breast
conserving surgery suitable for adjuvant whole breast radiation
therapy (RT) are eligible for the study. The trial
explores the value of adding a tumor bed boost to whole
breast RT, and compares a shorter vs a standard dose fractionation
schedule in a two by two design. Seven Swiss
radio-oncology units have recruited a total of 18 patients
until November 2011. This is a very important and exciting
trial for IBCSG because this is the �rst radiotherapy
trial that we have conducted.
The trial reached the original accrual goal of 610 patients
on October 28, almost two years ahead of the original
schedule. The sponsoring group TROG has issued an
amendment to increase the total sample size to 1600 patients
in order for the study to have 90% power to detect
a difference in local recurrence rates between boost and no
boost treatment arms of 4% to 7%.
The recruitment to the trial was stopped on December
21 after having included 640 patients. The amendment is
currently in the activation process, and once it will have
been approved the trial will be re-opened in Switzerland.
IBCSG 40-11 / MA.32
This phase III randomized trial of metformin versus placebo
on recurrence and survival in early stage breast cancer
has been developed by the Canadian NCIC Clinical Trials
COOPERATIVE GROUPS
Group. With a planned sample size of 3582, the plan is to
compare invasive disease free survival (IDFS) between subjects
treated with metformin (850 mg po bid for 5 years)
versus placebo in addition to standard adjuvant therapy.
The rationale to study metformin is based on observations
in epidemiologic studies, where metformin use in diabetics
was associated with reduced overall cancer risk and
mortality. Clinically, observational research has identi�ed
higher response rates to neoadjuvant systemic therapy in
diabetic breast cancer patients receiving metformin for
their diabetes compared to diabetic breast cancer patients
who do not receive metformin or to non-diabetic breast
cancer patients. Metformin may exert anti-tumour effects
through both insulin-dependent and insulin-independent
mechanisms in women with a broad range of insulin levels
commonly seen in newly diagnosed breast cancer.
The trial is currently being conducted in North America,
but has triggered major interest in Europe as well, and a
UK based group as well as IBCSG have decided to participate.
Since sponsorship of NCIC CTG does not extend
to Europe, IBCSG has taken over the role of sponsor for
Switzerland. Most SAKK sites will participate, and the
activation process is ongoing.
Latest IBCSG publications
Regan MM, Leyland-Jones B, Bouzyk M, Pagani O, Tang
W, Kammler R, Dell’orto P, Biasi MO, Thürlimann B,
Lyng MB, Ditzel HJ, Neven P, Debled M, Maibach R,
Price KN, Gelber RD, Coates AS, Goldhirsch A, Rae
JM, Viale G; on behalf of the Breast International Group
(BIG) 1-98 Collaborative Group. CYP2D6 Genotype and
Tamoxifen Response in Postmenopausal Women with
Endocrine-Responsive Breast Cancer: The Breast International
Group 1-98 Trial. J Natl Cancer Inst. 2012 Mar
21;104(6):441-451.
Brown R, Butow P, Wilson-Genderson M, Bernhard J,
Ribi K, Juraskova I. Meeting the decision-making preferences
of patients with breast cancer in oncology consultations:
impact on decision-related outcomes. J Clin Oncol.
2012 Mar 10;30(8):857-62.
Correspondence:
Rudolf Maibach, PhD
IBCSG Coordinating Center
Ef�ngerstrasse 40, 3008 Berne
Tel. +41 31 389 91 96
rudolf.maibach@ibcsg.org
www.ibcsg.org
Schweizer Krebsbulletin � Nr. 2/2012 169