Post on 25-Dec-2016
Abstracts / The Breast 22 S3 (2013) S19–S63 S37
Clinical Issues: Radiation Oncology
PR51
PATTERNS OF FAILURE IN BREAST CANCER PATIENTS TREATED WITH MASTECTOMY WITHOUT RADIOTHERAPY
Tahir Mehmood, Muhammad Ali, Uzma Masood, Mazhar Ali Shah,
Shahid Hameed, Arif Jamshed
Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore,
Pakistan
Introduction: Pakistan has the highest rate of breast cancer for any
South Asian population and majority of the patients present with locally
advanced or metastatic disease. We report on patterns of failure and
survival in breast cancer patients treated with mastectomy and adjuvant
chemotherapy/hormonal therapy and without post mastectomy
radiotherapy (PMRT).
Materials and Methods: Between 1995 to 2009, the hospital information
system identified 428 women with pathologically confirmed breast
cancer. All patients were treated with mastectomy (including level
I-II axillary dissection) without PMRT. 71% of the patients received
doxorubicin based chemotherapy either in neo-adjuvant or adjuvant
setting. 56% of the patients with positive ER/PR receptors also received
hormonal manipulation. Median age was 50 years (range 22-88 years).
Axillary nodes were clinically palpable in 32% of the patients at
presentation. Median number of dissected lymph nodes were 15 (range
1-33). Distribution of pathologic tumor size was up to 2 cm, 2.1 to 5 cm,
and more than 5 cm in 27%, 64%, and 9% of the patients respectively.
Distribution of pathologically positive number of lymph nodes (LN) was
zero, one to three, four to nine, and more than 10 in 71%, 17%, 5.5%, and
6.5% of the patients respectively. Patterns of failure and disease free
survival (DFS) were determined.
Results: Median follow-up duration was 5.4 years. Patterns of failure;
isolated local (LF) 4.5%, isolated regional (RF) 1.5%, loco-regional (LRF)
1%, distant (DF) 21%, and LRF alongwith DF were seen in 1.5% of the
patients respectively. Cumulative incidences for LF, RF and LRF with or
without DF for patients with zero, one to three, four to nine, and more
than 10 positive LN were 13%, 8.5%, 3% and 4.5% respectively (p = 0.000).
For patients with a tumor size of up to 2 cm, 2.1 to 5 cm, and more than
5 cm, these incidences were 6.5%, 17.5%, and 5% respectively (p = 0.000).
The 10 years DFS for the whole group was 62%. The 10 years DFS for
patients with zero, one to three, four to nine, and more than 10 positive
LN was 74%, 46%, 28% and 17% respectively (p = 0.000).
Conclusions: The role of PMRT may have some value in patients with
tumor size up to 5 cm and with up to three positive lymph nodes. This
merits further evaluation in large scale randomized trials.
PO52
ARE POSTCHEMOTHERAPY TARGET VOLUME ADEQUATE AS BOOST VOLUME FOR CONSERVED BREAST IN LOCALLY ADVANCED BREAST CANCER?
Sushma Agrawal, Mohammed Waseem Raza, Punita Lal, K.J.Maria Das,
Shaleen Kumar
Sanjay Gandhi postgraduate Institute of Medical Sciences, Lucknow, India
Introduction: There is no consensus on boost target volume delineation in
conserved breast in locally advanced breast cancer (LABC) after neoadjuvant
chemotherapy (NACT). Inclusion of prechemotherapy target volume has
the disadvantage of large volumes which will have a detrimental effect on
cosmesis. Inclusion of postchemotherapy target volume has the advantage
of smaller target volume but there could be a higher risk of recurrence.
We therefore did a retrospective analysis of LABC patients who underwent
breast conservation (BCS) after NACT to assess whether post NACT target
volumes are adequate for achieving local control.
Materials and Methods: Patients of LABC who underwent BCS and
radiotherapy after NACT, registered between 2007-2011 were the
subject of our analysis. After BCS, patients received whole breast
and supraclavicular radiotherapy (50 Gy/25 fractions/5 wk or 42.4
Gy/16#/3 wk) which was followed by boost (10-16 Gy/5-8#/1-1.5 wk).
After evaluating patterns of recurrence in these patients, the information
on lumpectomy specimen size, method of estimating tumour boost field
size (whether based on visible scar, cavity on CT scan, prechemotherapy
tumour size or postchemotherapy tumour size) was sought to gain an
insight on whether these had an impact on the local recurrence.
Results: 43 patients were the subject of this analysis. The median age
was 47 years, 42% were premenopausal and 58% were postmenopausal.
Histopathological subtypes were luminal A (23%), luminal B (23%), Her- 2
type (14%) and basal type (40%). (47.7%) patients had stage II disease and 12
(27.2%) had IIIA and 10 (22.7%) had IIIB disease at presentation. After NACT
33.3% patients acheived CR (complete response), 54.8% PR (partial response)
and 11.8% had SD (stable disease). The surgical margins around tumour in
lumpectomy specimens were based on pre-chemotherapy tumour size
in all patients. Radiotherapy planning scan revealed tumour cavity in 33
patients and clips in 19 patients. Boost target delineation was based on
visible scar: 4, tumour cavity: 5, prechemotherapy target volume: 5 and
post chemotherapy target volume: 27 patients. 2 patients did not receive
a boost. At a median followup of 27.2 months (4-71 months), no patient
had ipsilateral breast tumour recurrence (IBTR), one patient had ipsilateral
axillary node recurrence and four patients had distant metastases.
Conclusions: Postchemotherapy target volume seems to be safe as
boost volume delineation for radiotherapy in patients with LABC who
undergo BCS after NACT.
PO53
CLINICAL TARGET VOLUME IN CONSERVED BREAST IN LOCALLY ADVANCED BREAST CANCER
Sushma Agrawal, Punita Lal, K.J.Maria Das, Shaleen Kumar
Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
Purpose: It is important to characteristise the postoperative cavity in
conserved breast after neoadjuvant chemotherapy in locally advanced
breast cancer for accurate targeting during boost phase of intact breast
radiotherapy.This has not been described earlier. So the aim of this work
is to describe and measure the postoperative complexes (POC) and their
relationship to the chest wall and skin.
Materials and Methods: Patients of LABC who underwent BCS and
radiotherapy after NACT, registered between 2007-2012 were the subject
of our analysis. Appearances and measurements of CT postoperative
cavities were analyzed in a cohort of 56 patients who underwent a
radiation treatment planning CT scan before 3D conformal radiotherapy
to the intact breast.
Results: 56 patients were the subject of this analysis. The median time
interval from surgery to radiation was 3 months. In the radiotherapy
planning scan, POC could be identified in 85% patients, clips were found
in 56% patients. POC was situated in medial region (28%), central (30%)
and mediolateral (35%) region. The cavity visualization score was 5
(4%), 4 (33%), 3 (30%), 2 (28%) and 1 (5%).The POC shape was irregular
in 50%, oval in 40% and irregular ellipsoid in 10%. The POC texture was
homogenous in 28%, heterogenous in 72%.The POC was in direct contact
with the chestwall in 93% patients and with skin in 75% patients. The
mean shrinkage in POC from the time of surgery was 68%.
Conclusions: Postsurgical cavities in the conserved breast after
neoadjuvant chemotherapy are usually heterogeneous, irregular, and
are in contact with chest wall and skin in majority of cases. These results
have implications for treatment planning.