Addition of tumour infiltration depth and extranodal extension improves the prognostic value of the pathological TNM classification for early-stage oral squamous cell carcinoma.

AIMS: In the 8th edition of the American Joint Committee on Cancer TNM staging manual, tumour infiltration depth and extranodal extension are added to the pathological classification for oral squamous cell carcinoma. The currently available 8th TNM validation studies lack patients with conservative neck treatment, and changes in the classification especially affect patients with small tumours. The aim of this study was to determine the potential impact of the changes in the 8th edition pTNM classification on the prognosis and treatment strategy for oral squamous cell carcinoma in a well-defined series of pT1-T2 patients with long-term follow-up. METHODS AND RESULTS: Two hundred and eleven first primary pT1-T2 oral squamous cell carcinoma patients, with surgical resection as primary treatment, were analysed retrospectively. One hundred and seventy-three patients underwent a neck dissection, and 38 patients had frequent clinical neck assessments. Long-term follow-up (median 64 months) and reassessed tumour infiltration depth were available. Classification according to the 8th edition criteria resulted in 36% total upstaging with the T classification and 16% total upstaging with the N classification. T3-restaged patients (n = 30, 14%) had lower 5-year disease-specific survival rates than T2-staged patients (81% versus 67%, P = 0.042). Postoperative (chemo)radiotherapy could have been considered in another seven (3%) patients on the basis of the 8th edition criteria. CONCLUSIONS: Addition of tumour infiltration depth and extranodal extension in the 8th TNM classification leads to the identification of oral squamous cell carcinoma patients with a worse prognosis who might benefit from an improved postoperative treatment strategy.

FGFR Family Members Protein Expression as Prognostic Markers in Oral Cavity and Oropharyngeal Squamous Cell Carcinoma.

INTRODUCTION: Fibroblast growth factor receptor family member proteins (FGFR1-4) have been identified as promising novel therapeutic targets and prognostic markers in a wide spectrum of solid tumors. The present study investigates the expression and prognostic value of four FGFR family member proteins in a large multicenter oral cavity squamous cell carcinoma (OCSCC) and oropharyngeal squamous cell carcinoma (OPSCC) cohort. METHODS: Protein expression of FGFR1-4 was determined by immunohistochemistry on tissue microarrays containing 951 formalin-fixed paraffin embedded OCSCC and OPSCC tissues from the University Medical Center Utrecht and University Medical Center Groningen. Protein expression was correlated to overall survival using Cox regression models, and bootstrapping was performed as internal validation. RESULTS: FGFR proteins were highly expressed in 39-64 % of OCSCC and 63-79 % of OPSCC. Seventy-three percent (299/412) of OCSCC and 85 % (305/357) of OPSCC highly co-expressed two or more FGFR family member proteins. FGFR1 protein was more frequently highly expressed in human papillomavirus (HPV)-negative OPSCC than HPV-positive OPSCC (82 vs. 65 %; p = 0.008). Furthermore, protein expression of FGFR family members was not related to overall survival in OCSCC or OPSCC (p > 0.05). CONCLUSION: FGFR family members are frequently highly expressed in OCSCC and OPSCC. These FGFR family member proteins are therefore potential targets for novel therapies that are urgently required to improve survival of OCSCC and OPSCC patients.

Identification and validation of WISP1 as an epigenetic regulator of metastasis in oral squamous cell carcinoma.

Lymph node (LN) metastasis is the most important prognostic factor in oral squamous cell carcinoma (OSCC) patients. However, in approximately one third of OSCC patients nodal metastases remain undetected, and thus are not adequately treated. Therefore, clinical assessment of LN metastasis needs to be improved. The purpose of this study was to identify DNA methylation biomarkers to predict LN metastases in OSCC. Genome wide methylation assessment was performed on six OSCC with (N+) and six without LN metastases (N0). Differentially methylated sequences were selected based on the likelihood of differential methylation and validated using an independent OSCC cohort as well as OSCC from The Cancer Genome Atlas (TCGA). Expression of WISP1 using immunohistochemistry was analyzed on a large OSCC cohort (n = 204). MethylCap-Seq analysis revealed 268 differentially methylated markers. WISP1 was the highest ranking annotated gene that showed hypomethylation in the N+ group. Bisulfite pyrosequencing confirmed significant hypomethylation within the WISP1 promoter region in N+ OSCC (P = 0.03) and showed an association between WISP1 hypomethylation and high WISP1 expression (P = 0.01). Both these results were confirmed using 148 OSCC retrieved from the TCGA database. In a large OSCC cohort, high WISP1 expression was associated with LN metastasis (P = 0.05), disease-specific survival (P = 0.022), and regional disease-free survival (P = 0.027). These data suggest that WISP1 expression is regulated by methylation and WISP1 hypomethylation contributes to LN metastasis in OSCC. WISP1 is a potential biomarker to predict the presence of LN metastases.

Reproducibility and prognostic value of pattern of invasion scoring in low-stage oral squamous cell carcinoma.

AIMS: To evaluate and compare the prognostic value and reproducibility of different methods of pattern of invasion scoring in oral squamous cell carcinomas. The additional prognostic value to established histopathological prognostic factors was also analysed. METHODS AND RESULTS: The study group was confined to 211 previously untreated patients who underwent surgery for low-stage oral squamous cell carcinoma between 1997 and 2008. Median follow-up was 64 months (range 0-193 months). Pattern of invasion was scored using five previously described methods, at random and independently, by two observers. Pattern of invasion scoring showed moderate interobserver reproducibility (Cohen's κ = 0.52-0.58). The predominant pattern of invasion and the summed predominant and worst pattern of invasion were independent prognosticators for locoregional recurrence-free survival (LRRFS) [hazard ratio (HR): 2.1, P = 0.033 and HR 2.2, P = 0.024, respectively] and disease-specific survival (DSS) (HR 2.3, P = 0.032 and HR 2.1, P = 0.044, respectively) in multivariate Cox regression analyses. The Harrell's C index for proven prognostic histopathological factors was 0.66 for LRRFS and 0.67 for DSS. This improved to 0.69 and 0.73 with the addition of pattern of invasion. CONCLUSIONS: Pattern of invasion is an independent prognostic factor in low-stage oral squamous cell carcinoma. However, it has a moderate reproducibility, and the contributory value next to other prognostic histopathological factors is minimal.

Head and neck squamous cell carcinomas do not express EGFRvIII.

PURPOSE: To assess the prevalence of EGFRvIII, a specific variant of EGFR (epidermal growth factor receptor), in 3 well-defined cohorts of head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS: Immunohistochemistry for the specific detection of EGFRvIII using the L8A4 antibody was optimized on formalin-fixed, paraffin-embedded tissue using glioblastoma tissue. It was compared with EGFR and EGFRvIII RNA expression using a specific reverse transcription-polymerase chain reaction also optimized for formalin-fixed, paraffin-embedded tissue. Tissue microarrays including 531 HNSCCs of various stages with complete clinicopathologic and follow-up data were tested for the presence of EGFRvIII. RESULTS: None of the 531 cases showed EGFRvIII protein expression. Using an immunohistochemistry protocol reported by others revealed cytoplasmic staining in 8% of cases. Reverse transcription-polymerase chain reaction for the EGFRvIII transcript of the 28 highest cytoplasmic staining cases, as well as 69 negative cases, did not show expression in any of the tested cases, suggesting aspecific staining by a nonoptimal protocol. CONCLUSIONS: The EGFRvIII mutation is not present in HNSCC. Therefore, EGFRvIII does not influence treatment response in HNSCC and is not a usable clinical prognostic marker.

mTHPC-mediated photodynamic therapy of early stage oral squamous cell carcinoma: a comparison to surgical treatment.

BACKGROUND: mTHPC-mediated photodynamic therapy (PDT) is used for treatment of early head and neck squamous cell carcinoma. This study is a retrospective comparison of PDT with transoral surgery in the treatment of early primary squamous cell carcinoma of the oral cavity/oropharynx. METHODS: PDT data were retrieved from four study databases; surgical results were retrieved from our institutional database. To select similar primary tumors, infiltration depth was restricted to 5 mm for the surgery group. A total of 126 T1 and 30 T2 tumors were included in the PDT group, and 58 T1 and 33 T2 tumors were included in the surgically treated group. RESULTS: Complete response rates with PDT and surgery were 86 and 76% for T1, respectively, and for T2 63 and 78%. Lower local disease-free survival for PDT compared to surgery was found. However, when comparing the need for local retreatment, no significant difference for T1 tumors was found, while for T2 tumors surgery resulted in significantly less need for local retreatment. No significant differences in overall survival between surgery and PDT were observed. CONCLUSIONS: PDT for T1 tumors results in a similar need for retreatment compared to surgery, while for T2 tumors PDT performs worse. Local disease-free survival for surgery is better than for PDT. This may be influenced by the benefit surgery has of having histology available. This allows an early decision on reintervention, while for PDT one has to follow a wait-and-see policy. Future prospective studies should compare efficacy as well as morbidity.

EpCAM in carcinogenesis: the good, the bad or the ugly.

The epithelial cell adhesion molecule (EpCAM) is a membrane glycoprotein that is highly expressed on most carcinomas and therefore of potential use as a diagnostic and prognostic marker for a variety of carcinomas. Interestingly, EpCAM is explored as target in antibody-based therapies. Recently, EpCAM has been identified as an additional marker of cancer-initiating cells. In this review, we describe the controversial biological role of EpCAM with the focus on carcinogenesis: as an adhesion molecule, EpCAM mediates homophilic adhesion interactions, which in turn might prevent metastasis. On the other hand, EpCAM abrogates E-cadherin mediated cell-cell adhesion thereby promoting metastasis. Also, upon cleavage of EpCAM, the intracellular domain functions as a part of a transcriptional complex inducing c-myc and cyclin A and E. In line with these seemingly controversial roles, EpCAM overexpression has been associated with both decreased and increased survival of patients. Similarly, either induction or downregulation of EpCAM expression lowers the oncogenic potential depending on the cell type. As epigenetic dysregulation underlies aberrant EpCAM expression, we propose epigenetic editing as a novel approach to investigate the biological role of EpCAM, expanding the options for EpCAM as a therapeutic target in cancer.