Biomarkers in Locally Advanced Rectal Cancer: A Review

Locally advanced rectal cancers (LARC) are the subject of a rapidly evolving treatment paradigm. The critical timepoints where management decisions are required during the care of the LARC patient are: prior to the institution of any treatment, post neoadjuvant therapy and post-surgery. This article reviews the clinical, imaging, blood-based, tissue-based, and molecular biomarkers that can assist clinicians at these timepoints in the patient's management, in prognosticating for their LARC patients or in predicting responses to therapy in the multi-modality neoadjuvant treatment era.

Risk of nodal disease in patients with MRI-detected extramural vascular invasion in rectal cancer: a systematic review and meta-analysis

BACKGROUND

The impact of magnetic resonance imaging-detected extramural vascular invasion (mrEMVI) in distant metastasis is well known but its correlation with prevalence of lymph node metastasis is less studied. The aim of this systematic review and meta-analysis was to assess the prevalence of nodal disease in mrEMVI-positive and negative cases in rectal cancer.

METHODS

Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in PubMed, Web of Science, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2019.

RESULTS

Our literature search generated 10 studies (863 and 1212 mrEMVI-positive and negative patients, respectively). The two groups (mrEMVI-positive and negative) were significantly different in terms of nodal disease status (odds ratio [OR] 3.15; 95% confidence interval [CI] 2.12-4.67; p < 0.001). The prevalence of nodal disease was 75.90% vs 52.56% in the positive mrEMVI vs negative mrEMVI group, respectively (p < 0.001). The prevalence of positive lymph node in positive mrEMVI patients treated with neoadjuvant/adjuvant chemoradiotherapy (nCRT/CRT) (OR 2.47; 95% CI 1.65-3.69; p < 0.001) was less compared with the patients who underwent surgery alone (OR 6.25; 95% CI 3.74-10.44; p < 0.001).

CONCLUSION

The probability of positive lymph nodes in cases of positive mrEMVI is distinctly greater compared with negative cases in rectal cancer. Positive mrEMVI indicates risk of nodal disease prevalence increased by threefold in rectal cancer.

Pre-treatment carcinoembryonic antigen and outcome of patients with rectal cancer receiving neo-adjuvant chemo-radiation and surgical resection: a systematic review and meta-analysis

Neo-adjuvant chemo-radiation is the standard of care for patients with locally advanced rectal carcinoma. The aim of the present paper is to evaluate the relationship of the baseline serologic concentration of the carcinoembryonic antigen with the outcome. Data sources included MEDLINE and Web of Science databases. A systematic search of the databases by a predefined criterion has been conducted. Chemo-radiation followed by surgical resection of rectal tumors was the intervention of interest. From selected studies, the relationships between carcinoembryonic antigen and pathologic complete response, disease-free survival and overall survival were assessed. Carcinoembryonic antigen correlated significantly and inversely with the rate of pathologic complete responses (OR 2.00). Similar to this relationship, a low baseline carcinoembryonic antigen concentration was associated with a better disease-free survival (OR 1.88) and a better overall survival (OR 1.85). Heterogeneity of studies and publication bias were considerable in evaluating the relationship of baseline carcinoembryonic antigen and pathologic complete response. Baseline carcinoembryonic antigen should be regarded as a predictor of outcome of patients undergoing neo-adjuvant chemo-radiation. A calibration of the cutoff value from 5 to 3 ng/ml appears more appropriate to this patient population and should be evaluated in prospective trials.

Small carcinomas involving less than one-quarter of the rectal circumference: local excision is still associated with a high risk of nodal positivity

AIM

A study was carried out to determine the relationship between mesorectal lymph nodal involvement and T stage in a group of patients with a rectal cancer involving less than one-quarter of the rectal circumference, such as might be selected for local excision.

METHOD

The data of patients having rectal resection between 2010 and 2014 were prospectively entered in a rectal carcinoma registry. A model for describing tumours involving less than one quadrant of the rectal circumference was created to facilitate the evaluation process.

RESULTS

In all, 304 patients were included in the study. In 68 (22.4%) a small tumour (< 1 quadrant involved) was found. Of these, 26.5% had positive mesorectal lymph nodes (N+). In lesions of Stage ypT0 cancer 12.5% patients were node positive, in Stage Tis and T1 tumours there was no case of node positivity, but in Stage T2 and Stage T3 cancers the incidence of node positivity was 27.5% and 64%.

CONCLUSION

The study demonstrated that, even for small tumours involving only one rectal quadrant, the risk of lymph nodal involvement was about 25%. Had the patients undergone local excision the treatment would have been incomplete.

Expression of eukaryotic initiation factor 4 E in hypopharyngeal carcinoma

OBJECTIVES

To investigate the expression of eukaryotic initiation factor 4 E (eIF4E) in hypopharyngeal carcinoma compared with benign lesions, and the relationships between eIF4E expression and various clinicopathological parameters.

METHODS

Expression of eIF4E was analysed retrospectively in specimens from hypopharyngeal carcinomas and benign hypopharyngeal lesions using immunohistochemical staining and Western blotting. Tumours were classified using the tumour-node-metastasis staging system and the degree of histological differentiation was assessed.

RESULTS

A total of 55 hypopharyngeal carcinoma and 20 benign specimens were analysed. All the hypopharyngeal carcinoma samples were positive for eIF4E expression on immunohistochemistry, whereas the benign lesions were negative or weakly positive. Semi-quantitative assessment (eIF4E score) showed that eIF4E expression was significatly higher in hypopharyngeal carcinoma than in benign lesions. On Western blotting, eIF4E expression assessed using integrated optical density (IOD) was significantly higher in hypopharyngeal carcinoma than in benign lesions. The eIF4E score and IOD value were significantly associated with tumour stage, lymphatic metastasis and degree of differentiation. The IOD value was significantly higher in recurrent compared with initial cases.

CONCLUSIONS

eIF4E may play an important role in the development and metastasis of hypopharyngeal carcinoma;its expression may be helpful in establishing the diagnosis, stage and prognosis of this tumour type.

[Locally advanced rectal cancer management: which role for the pathologist in 2011?]

Locally advanced rectal cancers mainly correspond to lieberkünhien adenocarcinomas and are defined by T3-T4 lesions with or without regional metastatic lymph nodes. Such tumors benefit from neoadjuvant treatment combining chemotherapy and radiotherapy, followed by surgery with total mesorectum excision. Such a strategy can decrease the rate of local relapse and lead to an easier complementary surgery. The pathologist plays an important role in the management of locally advanced rectal cancer. Indeed, he is involved in the gross examination of the mesorectum excision quality and in the exhaustive sampling of the most informative areas. He also has to perform a precise histopathological analysis, including the determination of the circumferential margin or clearance and the evaluation of tumor regression. All these parameters are major prognostic factors which have to be clearly included in the pathology report. Moreover, the next challenge for the pathologist will be to determine and validate new prognostic and predictive markers, notably by using pre-therapeutic biopsies. The goal of this mini-review is to emphasize the pathologist's role in the different steps of the management of locally advanced rectal cancers and to underline its implication in the determination of potential biomarkers of aggressiveness and response.

Clinical impact of lymph node status in rectal cancer

Lymph node status at the time of diagnosis remains one of the principal indicators of prognosis in patients with rectal cancer. Involvement of loco-regional lymph nodes is relevant to surgical and clinical oncologists and continues to impact significantly upon local and systemic management strategies, in both neo-adjuvant and adjuvant settings. In this review, the clinical impact of lymph node status in the surgical management of rectal cancer is considered, with particular reference to the significance of lymphadenectomy and the potential implications for rectal tumours amenable to trans-anal excision. Current standards of care are reviewed and the extent to which the determination of lymph node status influences oncological decisions regarding neo-adjuvant and adjuvant therapies are discussed with areas of controversy highlighted.