Abstract 2310
Background
Although the current standard preoperative chemoradiotherapy (PCRT) for stage II/III rectal cancer decreases the risk of local recurrence, it does not improve overall survival and increase the likelihood of preoperative overtreatment, especially in patients without the circumferential resection margin (CRM) involvement.
Methods
Stage II/III rectal cancer without CRM involvement and lateral lymph node metastasis was radiologically defined by preoperative magnetic resonance imaging (MRI). Patients who received either PCRT followed by TME (PCRT group) or upfront surgery with TME (US group) between 2011 and 2016 were analyzed. We derived cohorts of PCRT group versus US group using propensity-score matching using staging, age, and distance from anal verge). Three-year relapse-free survival rate, disease-free survival (DFS), and overall survival (OS) were compared between two groups.
Results
A total of 221 patients were analyzed after propensity score matching. There were no differences in baseline characteristics. The median follow-up was 75 months (range, 28-101). No difference in 3-year relapse-free survival rate was noted between PCRT and US groups (89% vs 92% with US; P = 0.657). Likewise, there was no statistically significant difference in DFS (7.7 years vs 8.0 years with US; P = 0.162) and OS (8.1 years vs 8.3 years with US; P = 0.431), respectively. The rates of locoregional recurrence (2.9% vs 0% with US, P = 0.301) and distant metastasis (7.4% vs 7.1%, P = 1.0) at 3-years were not significantly different between two groups. Interestingly, approximately half of patients had pathologic stage I cancer in both groups (56% with PCRT vs 45% with US; P = 0.167) and 69% of patients in US group had not received adjuvant treatment, suggesting that upfront surgery without neoadjuvant therapy can be considered in early stage patients with good prognosis.
Conclusions
PCRT may not be required for all stage II/III rectal cancer patients, especially for the MRI-based intermediate-risk group (cT1-2/N1, cT3N0) without CRM involvement and lateral lymph node metastasis. Further prospective studies are warranted.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5612 - Evaluation of germ line mutational status among women with triple-negative breast cancer in Russia
Presenter: Elena Shagimardanova
Session: Poster Display session 2
Resources:
Abstract
4142 - Association of derived neutrophil-to-lymphocyte ratio (dNLR) with pathological complete response (pCR) after neoadjuvant chemotherapy (CT)
Presenter: Alberto Ocaña
Session: Poster Display session 2
Resources:
Abstract
1733 - Competing nomogram for late-period breast cancer-specific death in patients with early-stage hormone receptor-positive breast cancer
Presenter: Jianfei Fu
Session: Poster Display session 2
Resources:
Abstract
1978 - A Nomogram to Predict Pathologic Complete Response of Neoadjuvant Chemotherapy in Triple-Negative Breast Cancer Based on Simple Blood Indicators
Presenter: Fanrong Zhang
Session: Poster Display session 2
Resources:
Abstract
3062 - Identification of GSTP1 transferred by extracellular vesicles responsible for adriamycin-resistance in breast cancer cells
Presenter: Sujin Yang
Session: Poster Display session 2
Resources:
Abstract
5274 - Expression of X-linked Inhibitor of Apoptosis Protein (XIAP) and its Association with Clinicopathological Parameters in Invasive Breast Cancers
Presenter: Gayathri Devi
Session: Poster Display session 2
Resources:
Abstract
1324 - The prognostic significance of preoperative tumor marker (CEA, CA15-3) elevation in breast cancer patients
Presenter: Soo Youn Bae
Session: Poster Display session 2
Resources:
Abstract
4877 - Correlation of clinical and pathological features with the tumour microenvironment in DCIS. An institutional experience
Presenter: Ann Eapen
Session: Poster Display session 2
Resources:
Abstract
2471 - Correlation between radiologic complete response (rCR) in contrast-enhanced magnetic resonance imaging (CE-MRI) after neoadjuvant chemotherapy for early breast cancer and pathologic complete response and their impact in recurrence-free survival
Presenter: Ariadna Gasol Cudos
Session: Poster Display session 2
Resources:
Abstract
2632 - Ring-like uptake appearance on dedicated breast positron emission tomography before chemotherapy predicts outcome of neoadjuvant chemotherapy in breast cancer
Presenter: Norio Masumoto
Session: Poster Display session 2
Resources:
Abstract