REMARK scoring of biomarkers predicting lymph node metastasis in oral squamous cell carcinoma – A systematic review

Riya Jain; Suchitra Gosavi; Deepak Sethia; Priya Jain

doi:10.4103/srmjrds.srmjrds_116_22

REVIEW ARTICLE

Year : 2023 | Volume : 14 | Issue : 1 | Page : 33-40

REMARK scoring of biomarkers predicting lymph node metastasis in oral squamous cell carcinoma – A systematic review

Riya Jain¹, Suchitra Gosavi¹, Deepak Sethia², Priya Jain³
¹ Department of Oral and Maxillofacial Pathology, Government Dental College and Hospital, Nagpur, Maharashtra, India
² Department of Critical Care Medicine, Deenanath Mangeshkar Hospital, Pune, Maharashtra, India
³ Product Manager, Mastercard, Vadodara, Gujarat, India

Date of Submission	03-Sep-2022
Date of Decision	03-Dec-2022
Date of Acceptance	01-Jan-2023
Date of Web Publication	18-Mar-2023

Correspondence Address:
Dr. Riya Jain
Department of Oral and Maxillofacial Pathology, Government Dental College and Hospital, Medical Square, Nagpur - 440 003, Maharashtra
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/srmjrds.srmjrds_116_22

Abstract

Background: A universal and systematic protocol is essential for accurate reporting of biomarker studies. For unity in reporting biomarker studies, many guidelines were introduced, Recommendations for Tumor Marker Prognostic Studies (REMARK) being one of them. Aim: The purpose of this review is to evaluate the quality of published articles of biomarkers that predict metastasis in lymph nodes in oral squamous cell carcinoma (OSCC) by the use of the reporting recommendations for tumor marker prognostic (REMARK) guidelines. Methods: Comprehensive search was done in MEDLINE via PubMed and Cochrane from January 2015 to December 2019 to identify manuscripts evaluating biomarkers predicting lymph node metastasis in OSCC. The significance of the univariate and multivariate analysis was assessed for each manuscript, and P < 0.05 was considered statistically significant. Results: Thirty-six results were included for the qualitative synthesis. The mean REMARK score was 11.13 (range: 5.01–17.15). Biomarkers with the highest REMARK score were phospholipase C, cyclin D, CD44+/CD133+, and matrix metalloproteinase-9 (MMP-9). While biomarkers such as LGALS1, NCOA7, and TMOD1 were associated with high risk of bias, hence its use as a biomarker predicting lymph node metastasis is questionable. Conclusions: In our review of 36 manuscripts, manuscripts examining biomarkers evaluating lymph node metastasis in OSCC need an improvement in their reporting. Biomarkers such as phospholipase C, cyclin D, CD44+/CD133+, and MMP-9 can be used as a predictor of lymph node metastasis in OSCC.

Keywords: Biomarker, lymph node, metastasis, oral cancer, oral squamous cell carcinoma

How to cite this article:
Jain R, Gosavi S, Sethia D, Jain P. REMARK scoring of biomarkers predicting lymph node metastasis in oral squamous cell carcinoma – A systematic review. SRM J Res Dent Sci 2023;14:33-40

How to cite this URL:
Jain R, Gosavi S, Sethia D, Jain P. REMARK scoring of biomarkers predicting lymph node metastasis in oral squamous cell carcinoma – A systematic review. SRM J Res Dent Sci [serial online] 2023 [cited 2023 Mar 31];14:33-40. Available from: https://www.srmjrds.in/text.asp?2023/14/1/33/371997

Introduction

Cancer is a curse to humanity. Among all, oral cancer is the most catastrophic as it affects the patient both physically and emotionally. In accordance with GLOBOCAN 2018 data, of all cancers, 16.1% in men and 10.4% in women in India are oral cancer. An aggregate of 72,616 of deaths were announced in 2018 attributing to oral cancer.^[1] The 5-year survival rate in oral cancer patients is declining due to the complications associated with the disease.^[2] The most dreadful complication is metastasis. With the strides in treatment modalities, the survival curve of oral cancer patients has remarkably improved. However, those with multiple lymph node metastases or distant metastases still show very poor prognosis.^[3] Ancient strategies such as TNM (primary tumor size, nodal status, and distant metastasis) classification system are commonly and habitually utilized for determining the spread of cancer. It is well documented that a large number of patients with no evidence of nodal metastasis are subjected to supererogatory neck dissection.^[4]

During this era of machine learning and artificial intelligence, predicting the survival curve is feasible. Biomarkers have enabled scientists to envision tumorigenesis within the lymph nodes.^[5] With advancing technologies, the utilization of biomarkers in clinical pathology has become so commonplace that their validity is accepted with no questions. Biomarkers are of potential importance in the pathogenesis and treatment of oral squamous cell carcinoma (OSCC). Overexpression of a biomarker that is elevated in OSCC with lymph node metastasis will be of potential price to guide the onco-surgeon regarding the extent of resection to be performed.

Despite this, <1% of biomarkers stay clinically useful. The Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) criteria were formulated in 2005.^[6] REMARK criteria were formed with the goal of providing a standard checklist in reporting of biomarker studies to increase their validity.^[7]

This systematic review was conducted with the aim to investigate the quality of manuscripts using the REMARK criteria as a gold standard guideline.

Review question was formulated using PICO method:

Population: Cases of OSCC diagnosed histopathologically with lymph node metastasis
Intervention: Assessment of biomarker in patients with OSCC
Control: Patients without lymph node metastasis
Outcome: Whether a biomarker is potentially predictive in evaluating metastasis in lymph nodes in OSCC.

Methods

Protocol and registration

Our review proposal is registered on the PROSPERO public registry of systematic review (PROSPERO registration no: CRD42019144925), and Preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were strictly followed.

Literature search

PubMed and Cochrane databases were searched (January 1, 2015–December 31, 2019). The following search strategy was used to search “Oral Cancer (Ti/Ab) OR Oral Squamous Cell Carcinoma (Ti/Ab) AND Lymph node (Ti/Ab) AND Metastasis (Ti/Ab) AND Biomarker (Ti/Ab).” Filters applied for PubMed were comparative study, observational study, and review.

Eligibility criteria

Manuscripts giving data regarding the expression of biomarkers in predicting lymph node metastasis in OSCC evaluated by immunohistochemistry were included. Studies giving information about expression of biomarkers in predicting metastatic OSCC evaluated by any method apart from immunohistochemistry and manuscripts published in language other than English would not be included in the review.

Study selection

Two authors (RJ and SG) individually read the title and abstract of manuscripts obtained after the primary search. Studies which did not meet the criteria were excluded. Thereafter, full-text articles of the selected manuscripts were read and assessed for their eligibility to be included in the study. Any bias in inclusion was resolved by a third reviewer (DS).

Data collection process and data items

Data extraction sheet was designed to obtain information of: first author, year of publishing the manuscript, study place, biomarker studied, levels of biomarker, patient data (sample size, gender, age, and nodal status), characteristics of the specimen used for assay, inclusion and exclusion criteria of the study, and specific prognostic metrics (e.g., overall survival, disease-free survival, and recurrence-free survival).

Another subcriterion of the REMARK scoring which was assessed for each manuscript was significance of the univariate and multivariate analysis. Univariate analysis (n = 3), multivariate analysis (n = 1), or a combination of both were done (n = 18), and P < 0.05 was considered statistically significant.

Risk of bias in individual studies

The REMARK risk of bias tool was used for each manuscript to evaluate the risk of bias in individual studies [Table 1].^[8]

Table 1: Adapted from the 2005 recommendations for tumor marker prognostic study publication and the subsequent 2012 expanded recommendations for tumor marker prognostic study explanation and elaboration edition^[8]

Click here to view

Synthesis of results

Full-text articles of these manuscripts were scored using REMARK. It has a checklist of twenty items with multiple subcategories. Each OSCC prognostic biomarker manuscript was evaluated according to 48 separate subcriteria for the highest score of 20 points.

Results

Literature search results

The search identified 238 results (77 PubMed and 161 Cochrane results). The Cochrane results had 4 articles overlapping within the database itself. Hence, in total, 234 results were identified. After this, records were screened for title/abstract and 204 results were excluded. Sixty-seven results used methods other than immunohistochemistry in evaluating the biomarker, and 4 studies were assessing the marker in cancers other than OSCC. One hundred and sixteen results were evaluating prognostic factors other than lymph node metastasis, 4 results did not meet the required study design, and 3 articles were removed from the database and were no more available for viewing the abstract. Although 40 results were included in the final analysis, on reading the full text of the articles, 2 articles were assessing factors other than lymph node metastasis, 1 article did not meet the required study design, and 1 article was in Chinese and the abstract was unable to be obtained despite trying to contact the authors. Hence, finally 36 results were included for the qualitative synthesis [Figure 1].

Figure 1: PRISMA guideline flowchart for selection of manuscripts for qualitative synthesis. PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses

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Study characteristics

Thirty-six articles met the criteria for inclusion. As shown in [Table 2], the mean REMARK score was 11.13 (5.07–17.15). All manuscripts mentioned their marker and mentioned whether the marker is clinically useful in the discussion section (n = 36).

Table 2: Recommendations for Tumor Marker Prognostic Studies scoring of individual manuscripts

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Risk of bias assessment

Each manuscript was evaluated and scored for each criterion in the REMARK guideline. The journals had an average impact factor of 2.79 (0.51–7.09). The mean REMARK score was 11.13. The mean sample size was 152. From all the articles, material and methods section (50%) was least properly reported followed by Introduction, Results, and Discussion section with a median score of 27 (75%), 23 (64%) and 31 (86%), respectively. Within the methodology subcriteria, the patient details and specimen characteristic subdivisions had a low REMARK score of median number 11.5 (32%) and 12.5 (35%), respectively from the REMARK criteria,the ones with the lowest score were: study/flow diagram, testing their model for their assumption, sensitivity analysis, internal or external validation studies (n = 2); and state that “all data was accounted for” or “no missing data occurred” (n = 3). Not even a single study described sample size calculation. The sample size ranged from 34 to 443.

Results of individual studies

The largest number of studies was carried out in the Asian Continent and only one study was reported from South America [Table 3]. Majority showed statistically significant results. However, in a few studies (n = 13), no comment was made on statistical significance of the same. Survival metric is the single most and easy way to predict the disease outcome or prognosis. Encouragingly, a variety of metrics such as overall survival, disease-free survival, disease-specific survival, hazard ratio, or a combination of two or more were utilized. In 9 of the 36 studies, significance to single survival metric was seen, while in 15 studies, significance to more than one survival metric was seen [Table 3].

Table 3: Continuous and categorical variable statistical analysis with recommendations for tumor marker prognostic study scores

Click here to view

Discussion

OSCC is among the 10 common cancers in the world.^[1] Treatment of patients with neck metastasis is salvage surgery, and it severely degrades the quality of life of the patient. The postsurgical complications associated with such extensive surgeries leave the patient handicapped for entire life. Many studies have concluded that preoperative staging for lymph node status by routine clinical examination and imaging cannot be relied upon to detect early cervical metastatic disease.^[45] Staging by TNM classification system is routinely used for determining the extent of disease. A large number of patients undergo unnecessary neck dissection due to the unknown status of metastasis.^[4]

As we march toward an era of precision medicine and targeted therapy, the reliance on biomarkers for validation of treatment planning is accepted without any question. The field of biomarker development is laborious and highly technique sensitive. Hence, prudent reporting of manuscripts with elaborated methodology and interpretation of results is of paramount importance not only to maintain the quality of manuscripts but also patient care.^[46] Therefore, through this systematic review, we aimed to evaluate the validity of manuscripts evaluating biomarkers predicting lymph node metastasis in OSCC.

None of the publications mentioned that they follow REMARK or any other guidelines in reporting of their study. In our review of 36 manuscripts, biomarkers with the highest REMARK score were phospholipase C, cyclin D, CD44+/CD133+, and matrix metalloproteinase-9 (MMP-9). Hence, they can be used as a predictor of lymph node metastasis in OSCC. The study done by Zhu et al.,^[28] 2014, on phospholipase C had the highest REMARK score of 17.15 and hence the least risk of bias. While the study done by Li et al.,^[43] 2018, on LGALS1 had the least REMARK score of 5.07 and the highest risk of bias. A prospective study done by Zhu et al.,^[28] 2014, on phospholipase C had the highest REMARK score of 17.15. In this study, 232 OSCC patients at clinical stage III/IVA232 OSCC Formalin fixed paraffin embedded (FFPE) blocks. Low phospholipase C levels correlated with better overall survival, disease-free survival, local regional-free survival, and distant metastasis-free survival. Since this study has the lowest risk of bias, it can be concluded that Phospholipase C can be used as a marker to detect lymph node metastasis in OSCC.

It was noted that journals with a good impact factor had a better quality publication.^{[17],[18],[36]} This is consistent with REMARK score of equal to or more than mean score. The impact factor for the journals were recorded at the time of this study which are subject to change. This may skew the observations [Table 1]. On evaluating the parameter of levels of biomarkers predicting lymph node metastasis in OSCC in each manuscript, we found that expression of the biomarker increased with progression to lymph node metastasis in majority of studies, i.e., n = 29. 7 out of 36 studies had lowest REMARK score (RECK, RUNX3, interleukin 37, cathepsin B, Tie2, Naa10p N-a acetyltransferase 10 protein, and annexin 1) the marker with the least REMARK score was LGALS1 which was in line with the study done by Li et al.^[43]All studies, however, showed statistically significant results. LGALS1 overexpression is associated with invasiveness and metastasis of oral cancer by influencing the activation of P38 mitogen-activated protein kinase pathway in oral cancer. However, the study is associated with a high risk of bias, hence its use as a biomarker predicting lymph node metastasis is questionable.

From the results of our systematic review, we conclude that manuscripts analyzing biomarkers predicting lymph node metastasis in OSCC should improve their quality of writing. However, in a wide arena of biomarker field, our review with 36 publications is relatively small. Hence, our ability to extrapolate the results widely is limited. At the same time, this also opens up opportunity for further research in this field.

An array of biomarkers are discovered over the past 20 years to aid in higher patient care. In parallelism, a wide area of biomarker pathology still remains below cowl. The biomarker predicting lymph node metastasis is one such arena. Therefore, steps ought to be taken in order to facilitate increased research of clinically useful biomarkers in the clinic, whereas additionally also avoiding the introduction of biomarkers that have not been sufficiently validated and therefore may be potentially prejudicial to patient care.^[47] In our review of 36 manuscripts, biomarkers with the highest REMARK score were phospholipase C, Cyclin D, CD44+/CD133+, and MMP-9. While biomarkers such as LGALS1, NCOA7, and TMOD1 were associated with a high risk of bias, hence its use as a biomarker predicting lymph node metastasis is questionable. Hence, they can be used as a predictor of lymph node metastasis in OSCC.

Conclusions

With the support of this review, we conclude that manuscripts evaluating biomarkers of lymph node metastasis need to improve their quality of reporting. Abiding by reporting guidelines like REMARK criteria will solve this pitfall and improve our literature.

Patient consent

Since it is a systematic review on published studies, patient consent was not necessary.

Acknowledgments

We wish to extend our sincere gratitude toward Dr. Niharika Mistry for acting as the third observer to reduce the inter-observer variability.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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