165 CLINICAL IMPACT OF PREOPERATIVE SERUM P53 ANTIBODY TITERS IN 1,487 PATIENTS WITH ESOPHAGEAL CARCINOMA: A MULTI-INSTITUTIONAL STUDY

Although previous reports showed clinicopathological and diagnostic significance of serum p53 antibody in esophageal squamous cell carcinoma, all those reports analyzed only 100 to 200 patients at single institute. This study was designed as a multi-institutional study promoted by the Japan Esophageal Society to elucidate the clinical significance of serum p53 antibody in esophageal cancer treatment. Methods A total of 1,487 patients, from 15 hospitals of Japan, with esophageal carcinoma surgically treated between 2008 and 2016 were enrolled in this retrospective study. We used 1.30 U/ml as a cutoff for classifying patients into positive and negative groups. And we attempted to analyze only positive cases. A receiver operating characteristic curve was constructed to assess serum p53 antibody cutoff levels to differentiate poor prognosis. We used 9.82 U/ml as a cutoff for classifying patients into low and high groups. Univariate and multivariate analyses were used to evaluate the clinicopathological and prognostic significance of pretreatment level of serum p53 antibody. Results There were significant relationships between serum p53 antibody level and tumor depth (p = 0.002), nodal status (p = 0.027) and pathological stage (p = 0.002). The positive serum p53 antibody group had a no significantly worse overall survival than that of the negative group (p = 0.699). The high serum p53 antibody group had a significantly worse overall survival than that of the low group (p = 0.024). However, the difference was not significant in the multivariate analysis (p = 0.137). Conclusion Although high level (>9.82 U/ml) of pretreatment serum p53 antibody might be associated with poor prognosis for patients with esophageal cancer, high serum p53 antibody was not an independent risk factor.

Significance of Serum p53 Antibody as a Tumor Marker in Colorectal Cancer

Objective. We examined serum anti-p53 antibodies (S-p53Ab) in colorectal cancer. Specifically, we retrospectively investigated the use of S-p53Ab as a prognostic marker after surgery for colorectal cancer. Materials and Methods. The levels of S-p53Ab, carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9) were measured in 160 colorectal cancer patients who underwent surgical treatment. The rate of postoperative change (RPC) in the S-p53Ab titer was calculated as [subsequent antibody titer-lowest titer]/lowest titer. Results. A relationship between recurrence and RPC in the S-p53Ab titer was not observed in patients who tested negative for S-p53Ab preoperatively. In addition, no patients, who tested negative for S-p53Ab preoperatively, tested positive for S-p53Ab at the follow-up after surgery. Of the patients who tested positive for S-p53Ab preoperatively, those recurrences had a significantly higher RPC compared with those who did not (p<0.001). Conclusions. Although S-p53Ab is not a significant tumor marker in patients who test negative preoperatively, increases in the S-p53Ab titer should be continuously monitored and measured in patients who are positive for this antibody preoperatively, regardless of whether they later test negative.

The utility or lack thereof regarding serum p53 antibody for detecting ulcerative colitis-associated colorectal cancer in the era of immunosuppressive therapy.

Background: Serum anti-p53 antibodies (Abs) have been considered useful for the early detection of ulcerative colitis-associated colorectal cancer (CAC). However, since the spread of immunosuppressive therapy for ulcerative colitis (UC) treatment in the 2010s, we have experienced a low prevalence of anti-p53 Abs in UC patients. The present study thus examined the utility of serum p53 Abs for detecting CAC in the era of immunosuppressive therapy. Methods: A series of 320 consecutive surgical cases of UC patients between April 2008 and March 2019 were enrolled in this study. Patients with no serum anti-p53 Abs data were excluded. Of the 250 patients analyzed, 219 had no carcinoma or dysplasia (Group non-CAC), and 31 had carcinoma or dysplasia (Group CAC). Serum anti-p53 Abs were detected with an enzyme-linked immunosorbent assay. Immnohistochemical detection was performed in Group CAC. Immunosuppressive therapy included a history of medication with prednisolone >20 mg/day, immunosuppressant drugs, immunomodulator drugs or biologic therapies for UC. Results: Immunosuppressive therapy was performed in 98.1% of Group non-CAC and 80.6% of Group CAC. There were no marked differences in serum anti-p53 Abs positivity between Groups non-CAC and CAC (8.7% vs. 3.2%, p =0.30). p53 staining positivity was noted in 90.3% of Group CAC, and the rate of serum p53 positivity was significantly lower in patients with immunosuppressive therapy than in those without in Group CAC (0.0% vs. 16.7%, p =0.04). Conclusions: The utility of serum p53 Abs for detecting CAC is dubious in the era of immunosuppressive therapy.