Small and Thin Oral Squamous Cell Carcinomas may Exhibit Adverse Pathologic Prognostic Features

New Histopathologic Risk Model for Early T-stage Oral Squamous Cell Carcinoma: Focusing on a Modified Worst Pattern of Invasion System and a New Tumor Budding Score

Oral squamous cell carcinoma (OSCC) is treated based on the TNM staging. However, early T-stage OSCC still exhibits substantial nodal metastasis and death rates. Recent literature highlights the independent prognostic value of worst pattern of invasion (WPOI) and tumor budding in OSCC. Nevertheless, WPOI-5 is uncommon in early T-stage OSCC, and the definitions of tumor budding and WPOI-4 overlap. Moreover, WPOI assessment is subjective, and tumor budding evaluation varies across studies. To address these limitations, we aimed to develop a modified WPOI system and a novel tumor budding scoring system that assesses single cells and high-density tumor budding. We also evaluated a new histopathologic risk model for early T-stage OSCC. The study cohort comprised 37 pT1 and 64 pT2 OSCCs. The modified WPOI demonstrated superior interobserver agreement compared with the original system (κ value: 0.98 vs. 0.53). In the multivariate analysis, modified WPOI and tumor budding score were independent prognostic factors for nodal metastasis and disease-free survival, while modified WPOI predicted disease-specific survival. By integrating these factors, our risk model stratified the patients into 3 groups. Notably, the intermediate-risk and high-risk groups exhibited significantly higher rates of nodal metastasis, recurrence, and tumor-related death. Conversely, none in the low-risk group had nodal metastasis or succumbed to the disease. Our model offered simplified scoring and potentially improved prognostic predictions. In conclusion, we've developed a modified WPOI system, a new tumor budding scoring system, and a reliable risk model that classifies early T-stage OSCC patients into distinct risk groups with significant prognostic differences.

Impact of worst pattern of invasion on prognosis of oral squamous cell carcinoma: a systematic review and meta-analysis

OBJECTIVE

The relationship between the worst pattern of invasion (WPOI) and the prognosis of oral squamous cell carcinoma (OSCC) remains controversial. This systematic review and meta-analysis was performed to determine the impact of the WPOI on the prognosis of OSCC.

METHODS

Studies from six databases were assessed for quality using the Newcastle-Ottawa Scale, and data were analyzed using Stata software.

RESULTS

Eighteen studies involving 3954 patients showed that patients with a WPOI of 4 to 5 had significantly worse overall survival, disease-specific survival, and disease-free survival than patients with a WPOI of 1 to 3. Significant associations of the WPOI with locoregional recurrence and mortality were found.

CONCLUSION

A higher WPOI was significantly associated with a worse prognosis of OSCC across various outcomes. Incorporating the WPOI into standard histopathological assessments may guide personalized treatments and improve outcomes.

Perineural invasion predicts poor survival and cervical lymph node metastasis in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) usually invades peripheral nerves through a process known as perineural invasion (PNI), recognized as an adverse factor considered for the administration of postoperative adjuvant therapy. The aim of this study was to assess the impact of PNI on survival and cervical lymph node metastasis in a cohort of OSCC patients.

MATERIAL AND METHODS

Presence, location and extension of PNI were assessed in a cohort of 57 paraffin-embedded OSCC resections. Clinico-pathological variables were obtained from each case. Five-year overall survival (OS) and 5-year disease-specific survival (DSS) curves were constructed according to the Kaplan-Meier method and compared with log-rank test. The Cox proportional hazard model was used to assess the role of PNI as an independent risk factor related to poor survival, and a binary logistic regression was performed to estimate the predictive value of PNI for regional lymph node metastasis.

RESULTS

PNI was observed in 49.1% of the cases, affecting only small nerves. Peritumoral PNI was the most common location, and multifocal PNI the most frequent extent. Most PNI positive cases had cervical metastasis (p=0.001), and PNI was more frequent in stages III-IV than in I-II (p=0.02). The five-year OS and the 5-year DSS decreased in PNI positive and peritumoral PNI cases. PNI was an independent risk factor for poor 5-year OS and poor 5-year DSS. The odds for cervical lymph node metastasis were of 6.076 (p=0.006) and 10.257 (p=0.007) for PNI and Tumor budding (TB) positive cases, respectively.

CONCLUSIONS

PNI is a frequent finding in OSCC and an independent risk factor for poor OS and DSS. PNI and TB are both risk factors associated to an increased likelihood for the development of lymph node metastasis. Therefore, we suggest further investigations to test the combined PNI-TB scoring system in risk stratification models for OSCC.

Prognostic impact of lymphovascular and perineural invasion in squamous cell carcinoma of the tongue

This study aimed to investigate the prognostic impact of lymphovascular and perineural invasions in patients with squamous cell carcinoma of the tongue who received surgery-based treatment at our institution between January 2013 and December 2020. Patients were divided into four groups based on the presence of perineural (P-/P +) and lymphovascular invasions (V-/V +): P-V-, P-V + , P + V-, and P + V + . Log-rank and Cox proportional hazard models were used to evaluate the association between perineural /lymphovascular invasion and overall survival (OS). Altogether, 127 patients were included, and 95 (74.8%), 8 (6.3%), 18 (14.2%), and 6 (4.7%) cases were classified as P-V-, P-V + , P + V-, and P + V + , respectively. Pathologic N stage (pN stage), tumor stage, histological grade, lymphovascular invasion, perineural invasion, and postoperative radiotherapy were significantly associated with OS (p < 0.05). OS was significantly different among the four groups (p < 0.05). Significant between-group differences in OS were detected for node-positive (p < 0.05) and stage III-IV (p < 0.05) cases. OS was the worst in the P + V + group. Lymphovascular and perineural invasions are independent negative prognostic factors for squamous cell carcinoma of the tongue. Patients with lymphovascular and/or perineural invasion may have significantly poorer overall survival than those without neurovascular involvement.