Figures & data
Table 1. Characteristics of the included studies.
Table 2. Synthesis of data extracted from the included studies related to outcomes pooled in the meta‐analysis.
Table 3. Quality score according to the REMARK guidelines.
Table 4. Pooled hazard ratios and 95% confidence intervals.
Sakata K, Someya M, Nagakura H, et al. Brachytherapy for oral tongue cancer: an analysis of treatment results with various biological markers. Jpn J Clin Oncol 2008;38:402–7. Kim SJ, Shin HJ, Jung KY, Baek SK, et al. Prognostic value of carbonic anhydrase IX and Ki-67 expression in squamous cell carcinoma of the tongue. Jpn J Clin Oncol 2007;37:812–9. Choi SW, Kim JY, Park JY, et al. Expression of carbonic anhydrase IX is associated with postoperative recurrence and poor prognosis in surgically treated oral squamous cell carcinoma. Hum Pathol 2008;39:1317–22. Roh JL, Cho KJ, Kwon GY, et al. The prognostic value of hypoxia markers in T2-staged oral tongue cancer. Oral Oncol 2009;45:63–8. Eckert AW, Lautner MH, Schütze A, et al. Co-expression of Hif1alpha and CAIX is associated with poor prognosis in oral squamous cell carcinoma patients. J Oral Pathol Med 2010;39:313–7. Han MW, Lee HJ, Cho KJ, et al. Role of FDG-PET as a biological marker for predicting the hypoxic status of tongue cancer. Head Neck 2012;34:1395–402. Kondo Y, Yoshikawa K, Omura Y, et al. Clinicopathological significance of carbonic anhydrase 9, glucose transporter-1, Ki-67 and p53 expression in oral squamous cell carcinoma. Oncol Rep 2011;25:1227–33. Brockton NT, Klimowicz AC, Bose P, et al. High stromal carbonic anhydrase IX expression is associated with nodal metastasis and decreased survival in patients with surgically-treated oral cavity squamous cell carcinoma. Oral Oncol 2012;48:615–22. Heo K, Kim YH, Sung HJ, et al. Hypoxia-induced up-regulation of apelin is associated with a poor prognosis in oral squamous cell carcinoma patients. Oral Oncol 2012;48:500–6. Pérez-Sayáns M, Suárez-Peñaranda JM, Pilar GD, et al. Expression of CA-IX is associated with advanced stage tumors and poor survival in oral squamous cell carcinoma patients. J Oral Pathol Med 2012;41:667–74. Hwa JS, Kwon OJ, Park JJ, Woo SH, et al. The prognostic value of immunohistochemical markers for oral tongue squamous cell carcinoma. Eur Arch Otorhinolaryngol 2015;272:2953–9. Yang JS, Lin CW, Chuang CY, et al. Carbonic anhydrase IX overexpression regulates the migration and progression in oral squamous cell carcinoma. Tumour Biol 2015;36:9517–24. Vasconcelos MG, Vasconcelos RG, Pereira de Oliveira DH, et al. Distribution of hypoxia-inducible factor-1α and glucose transporter-1 in human tongue cancers. J Oral Maxillofac Surg 2015;73:1753–60. Simões-Sousa S, Granja S, Pinheiro C, et al. Prognostic significance of monocarboxylate transporter expression in oral cavity tumors. Cell Cycle 2016;15:1865–73. Brockton NT, Lohavanichbutr P, Enwere EK, et al. Impact of tumoral carbonic anhydrase IX and Ki-67 expression on survival in oral squamous cell carcinoma patients. Oncol Lett 2017;14:5434–42. Sáenz-de-Santa-María I, Bernardo-Castiñeira C, Secades P, et al. Clinically relevant HIF-1α-dependent metabolic reprogramming in oropharyngeal squamous cell carcinomas includes coordinated activation of CAIX and the miR-210/ISCU signaling axis, but not MCT1 and MCT4 upregulation. Oncotarget 2017;8:13730–46. Peterle GT, Maia LL, Trivilin LO, et al. PAI-1, CAIX, and VEGFA expressions as prognosis markers in oral squamous cell carcinoma. J Oral Pathol Med 2018;47:566–74. Eckert AW, Horter S, Bethmann D, et al. Investigation of the prognostic role of carbonic anhydrase 9 (CAIX) of the cellular mRNA/protein level or soluble CAIX protein in patients with oral squamous cell carcinoma. Int J Mol Sci 2019;20:375.