No correlation between pretreatment serum CEA levels and tumor volume in locally advanced rectal cancer patients

Analysis of unexplained carcinoembryonic antigen elevation after curative treatment of locally advanced rectal cancer

BACKGROUND

To analyze the causes and patterns of unexplained carcinoembryonic antigen (CEA) elevation after curative treatment in locally advanced rectal cancer patients.

METHODS

Among the 1309 locally advanced rectal cancer patients treated with curative resection and radiotherapy between January 2001 and June 2011, 325 patients who postoperatively developed abnormal CEA elevation were reviewed. The unexplained CEA elevation was defined as a CEA level higher than 5 ng/mL with no evidence of cancer recurrence at the time of elevation.

RESULTS

Of the 325 patients, 143 (44%) had unexplained CEA elevations. The causes were categorized as delayed recurrence (n = 29, 20%), non-colorectal malignancy (n = 10, 7%), and non-malignancy-related conditions (n = 104, 73%). Shorter intervals between treatment and the first CEA elevation, and a higher peak CEA level, were observed in the delayed recurrence group compared with the non-colorectal malignancy or non-malignancy-related group (intervals of 6.8 vs. 44.9 vs. 23.2 months, respectively, p = 0.002; and peak CEA levels of 9.9 vs. 7.1 vs. 6.2 ng/mL, respectively, p = 0.034). In patients who showed delayed recurrence, the interval between the first CEA elevation and diagnosis of recurrence was a median of 13.0 months (range 3.8-60.6 months). Smoking was the most common cause for non-malignancy-related conditions. The patterns of unexplained CEA elevations were defined as sporadic (n = 78, 55%), stationary (n = 37, 26%), and increasing (n = 28, 20%). The patterns were significantly different depending on the cause (p < 0.001).

CONCLUSIONS

Analysis of the patterns of unexplained CEA elevations is a reasonable approach to predict the cause of the cancer.

Predictive Response Value of Pre- and Postchemoradiotherapy Variables in Rectal Cancer: An Analysis of Histological Data

Background. Neoadjuvant chemoradiotherapy (nCRT) followed by curative surgery in locally advanced rectal cancer (LARC) improves pelvic disease control. Survival improvement is achieved only if pathological response occurs. Mandard tumor regression grade (TRG) proved to be a valid system to measure nCRT response. Potential predictive factors for Mandard response are analyzed. Materials and Methods. 167 patients with LARC were treated with nCRT and curative surgery. Tumor biopsies and surgical specimens were reviewed and analyzed regarding mitotic count, necrosis, desmoplastic reaction, and inflammatory infiltration grade. Surgical specimens were classified according to Mandard TRG. The patients were divided as "good responders" (Mandard TRG1-2) and "bad responders" (Mandard TRG3-5). According to results from our previous data, good responders have better prognosis than bad responders. We examined predictive factors for Mandard response and performed statistical analysis. Results. In univariate analysis, distance from anal verge and ten other postoperative variables related with nCRT tumor response had predictive value for Mandard response. In multivariable analysis only mitotic count, necrosis, and differentiation grade in surgical specimen had predictive value. Conclusions. There is a lack of clinical and pathological preoperative variables able to predict Mandard response. Only postoperative pathological parameters related with nCRT response have predictive value.

Correlation of rectal tumor volumes with oncological outcomes for low rectal cancers: does tumor size matter?

PURPOSES

Several reports have described a relationship between tumor volume and oncological outcomes for certain cancers. There is paucity of similar data for rectal cancer. We conducted this study to establish whether tumor volume, mesorectal volume, and the tumor volume to mesorectal volume ratio (TV/MRV), evaluated by magnetic resonance imaging (MRI), affect the oncological outcomes of patients with rectal cancer.

METHODS

We performed volumetric analysis of rectal tumors from magnetic resonance imaging (MRI) images and assessed their correlation with oncological outcomes, using clinical and radiological databases.

RESULTS

The subjects of this study were 25 of 35 patients who underwent rectal cancer surgery after staging with MRI, after the exclusion of 7 patients for whom MRI images could not be retrieved and 3 patients who had metastases identified at diagnosis. Tumor volume (TV) was a significant predictor of overall survival hazard ratio (95% CI); 5.8 (1.2-29), (P = 0.03). Mesorectal volume (MRV) and TV/MRV did not correlate with oncological outcomes.

CONCLUSIONS

We found a direct relationship between tumor volume and overall survival, which may be used to stratify rectal tumors for neoadjuvant therapy. A larger prospective study is required to confirm this correlation.

Genetic variations affecting serum carcinoembryonic antigen levels and status of regional lymph nodes in patients with sporadic colorectal cancer from Southern China

BACKGROUND

Serum carcinoembryonic antigen (sCEA) level might be an indicator of disease. Indeed, an elevated sCEA level is a prognostic factor in colorectal cancer (CRC) patients. However, the genetic determinants of sCEA level in healthy and CRC population remains unclear. Thus we investigated the genetic markers associated with elevated serum sCEA level in these two populations and its clinical implications.

METHODS AND FINDINGS

Genome-wide association study (GWAS) was conducted in a cohort study with 4,346 healthy male adults using the Illumina Omni 1 M chip. Candidate SNPs associated with elevated sCEA levels were validated in 194 CRC patients on ABI Taqman platform. Eight candidate SNPs were validated in CRC patients. The rs1047781 (chr19- FUT2) (A/T) was associated with elevated sCEA levels, and rs8176746 (chr9- ABO) was associated with the regional lymph metastasis in the CRC patients. The preoperative sCEA level was a risk factor for tumor recurrence in 5 years after operation (OR = 1.427, 95% CI: 1.005∼1.843, P = 0.006). It was also one of the risk factors for regional lymph node metastasis (OR = 2.266, 95% CI: 1.196∼4.293, P = 0.012). The sCEA level in rs1047781-T carriers was higher than that in the A carriers in CRC patients without lymph node metastasis (P = 0.006). The regional lymph node metastasis in patients with homozygote AA of rs8176746 was more common than that in the heterozygote AG carriers (P = 0.022). In addition, rs1047781-AT and TT CRC patients exhibited a worse disease-free survival than AA genotype carriers (P = 0.023).

CONCLUSIONS

We found candidate SNPs associated with elevated sCEA levels in both healthy males and CRC population. Rs1047781 (chr19- FUT2) may be the susceptible locus for recurrence of CRC in a population from Southern China.