Loss of CDX-2 expression is an independent poor prognostic biomarker in patients with early-stage deficient mismatch repair colorectal cancer

Single metachronous bone metastasis following rectal adenocarcinoma: A case report

Colorectal cancer (CRC) ranks as the third leading cause of cancer-related mortality in developed countries. While its incidence in early stages has increased due to screening programs, a significant number of patients experience the development of metastases either at the time of diagnosis or during follow-ups. Unlike certain other types of cancer, such as breast, prostate, or lung cancer, where bone tissue is a common site for secondary dissemination, CRC primarily spreads to the lymph nodes, liver and lungs. The occurrence of bone metastases from CRC is rare and usually coincides with tumor involvement in other locations. Risk factors for bone metastases include the location of the primary tumor, the age of the patients, KRAS mutations and the degree of tumor differentiation. Unlike metastases to the liver and lungs, bone metastases tend to be symptomatic, affecting the patient's quality of life and resulting in a poorer prognosis with shorter survival rates. The approach to patient management needs to be personalized. The present study describes the of a patient who underwent surgery for stage IV rectal adenocarcinoma and later developed a metastasis in the costal wall 79 months post-intervention, with no evidence of recurrence at other sites.

Expression of mismatch repair proteins, CDX-2, and p53 in colorectal adenocarcinoma and their association with clinicopathological characteristics

BACKGROUND

Microsatellite instability is caused by loss of expression of DNA mismatch repair (MMR) proteins, which are involved in one of significant pathways that lead to colorectal cancer development and progression. Both Cdx-2 and p53 play an inhibitory role in colorectal cancer and are related to some clinicopathological features.

AIM

To analyze the significance of expression of MMR proteins (MLH1, MSH2, PMS2, and MSH6), CDX-2, and p53 in colorectal adenocarcinoma.

METHODS

A total of 175 patients with colorectal adenocarcinoma who were operated at the Affiliated Hospital of Yangzhou University from January 2017 to March 2021 were selected. The expression levels of MLH1, MSH2, PMS2, MSH6, CDX-2, and p53 in colorectal cancer were detected by immunohistochemical method. The association of the expression of the above proteins with clinicopathological features of colorectal adenocarcinoma was explored by chi-square test, and Spearman rank correlation was used for correlation analysis.

RESULTS

Among 175 colorectal adenocarcinoma patients, there were 39 patients with negative expression of all four MMR proteins (22.3%). The negative expression of MSH2, MSH6, MLH1, and PMS2 was found in 12 (6.9%), 1 (0.6%), 17 (9.7%), and 28 (16.0%) cases, respectively. Among 91 colorectal adenocarcinoma patients, 34 (35.1%) had negative expression of CDX-2, and 7 (25%) had negative expression of p53 in colorectal adenocarcinoma. The negative expression of MMR proteins was significantly correlated with the age of onset, tumor site, and degree of differentiation in colorectal adenocarcinoma patients (P < 0.05), but had no significant correlation with patient gender, tumor invasion depth, or lymph node metastasis (P > 0.05). There was no correlation between the expression of MMRs protein and that of CDX-2 and p53 (P > 0.05).

CONCLUSION

The expression of MMR proteins is related to the age of onset, tumor site, and degree of differentiation. The detection of MMR proteins has important clinical significance for the early diagnosis of colorectal adenocarcinoma, the formulation of therapeutic plan, and the assessment of prognosis.