Pathological complete response may underestimate distant metastasis in locally advanced rectal cancer following neoadjuvant chemoradiotherapy and radical surgery: Incidence, metastatic pattern, and risk factors

A case of cT4b recto-sigmoidal cancer obtained pathological complete response by preoperative chemotherapy with 4 cycles of mFOLFOX6 plus panitumumab

“…The overall response rate was 82.6%, including 4.3% with pCR. A recent meta-analysis also showed that rectal cancer patients with pCR after chemoradiotherapy who received adjuvant chemotherapy showed significantly improved overall survival 18) . However, concomitant use of anti-EGFR antibody as postoperative adjuvant setting had detrimental effect in survival 19) .…”

Prognostic impact of acellular mucin pools towards the patients with locally advanced rectal cancer achieving pathological complete response after preoperative chemoradiotherapy

“…Reviewing the available series of studies, the prognostic implications of acellular mucin pools in resected rectal specimens from patients showing pCR are still not well understood and remain .5%, p = 0.003) compared with those without acellular mucin pools, which revealed acellular mucin pools as a possible indicator of aggressive biological behavior of the tumor. 9 Similarly, despite a lack of statistical evidence, Campos-Lobato and colleagues and Bhatti AB and colleagues both observed a tendency for pCR patients with acellular mucin pools to present increased distant metastasis and reduced DFS and OS rates. 16,18 Inconsistent with the results of these latter two studies, Lim and colleagues demonstrated that the presence of acellular mucin pools had no significant association with poor outcome in DFS (97.0% versus 93.0%, p = 0.131) and OS (96.8% versus 95.9%, p = 0.314) rates, which were rather similar between the patients with and without acellular mucin pools, respectively.…”

“…In the cohort in the study by Sun and colleagues, positive mucin 1 staining was significantly associated with the presence of acellular mucin pools, and the expression level was higher in patients with acellular mucin pools than in patients without acellular mucin pools. 9 Fourthly, we failed to record the number and location of acellular mucin pools in the bowel wall. The prognostic implication of different patterns of mucin pools warrants further investigation.…”

Pathological Response Has Survival Benefits for Rectal Cancer following Neoadjuvant Therapy

“…In past studies, the biological and genetic characteristic predictive factors of PCR included carcinoembryonic antigen (CEA) levels, hemoglobin (Hb) levels, neutrophillymphocyte ratio (NLR), and obesity [10][11][12][13][14]. In addition, the clinical predictive factors of PCR included the tumor size, nodal status, tumor histology, treatment type of chemotherapy and radiation therapy, as well as the interval from the completion of nCRT to surgery [6, [15][16][17].…”