Evolving Strategy for Surgical Management of Oral Cancer: Present and Future

Transtumoral approach and piecemeal resection (Steiner principle) for the treatment of tongue cancer at stage T1-T2: A pilot study

BACKGROUND

To assess the feasibility of maximizing negative margins with minimal resection of healthy tissue, as confirmed by intraoperative assessment. This approach aims to be safe, effective, and to be considered a standard procedure.

MATERIAL AND METHODS

A prospective pilot study. Peritumoral ink marking aided in identifying margins. Transtumoral incisions were made along the central line until healthy tissue was visible. If positive or close margins were identified, an extension was performed only in the involved area. The tumor bed and outer part of the tumor were inked to determine margins for intraoperative assessment of the specimen.

RESULTS

Twelve patients with oral squamous cell carcinoma participated in the study, comprising 3 men and 9 women, with a mean age of 58 years. Four patients were diagnosed with clinical stage I (T1N0), while eight were classified as stage II (T2 N0). All patients underwent ipsilateral neck dissection (levels I-III). Intraoperative outcomes included negative, positive, or close margins. The number of tissue blocks varied based on the size of the tongue tumor and the segments that required expansion to ensure a tumor-free margin (>1 mm), which was necessary in 8 patients. All final pathological reports indicated negative margins of >1 mm.

CONCLUSIONS

Piecemeal resection emerges as a feasible and oncologically sound procedure for achieving margins >1mm, which are deemed safe. Precisely identifying positive areas within the tumor proves significantly safer than en bloc resections. The prognoses observed in this series depended more on regional disease factors than on specific characteristics of the primary tumor.

Risk Factors for Feeding Tube Dependency in Patients Undergoing Function Preservation Surgery for Advanced-Stage Laryngohypopharyngeal Cancer

Dysphagia and feeding tube dependency commonly occur in patients with laryngeal or hypopharyngeal cancer (LHC) during and after treatment, often leading to poor functional outcomes. Therefore, we examined the factors related to feeding tube dependency among advanced-stage LHC patients undergoing curative surgery. This study included 69 consecutive patients who underwent conservative surgery for previously untreated, advanced-stage LHC (squamous cell carcinoma) between 2006 and 2016. Persistent feeding tube dependency was defined as 1 year or more after treatment completion. Binary logistic regression analysis was used to determine the factors associated with reactive prolonged and persistent feeding tube dependency. Cox proportional hazard regression analysis was used to determine the association between feeding tube dependency and survival. None of the study patients had a prophylactic feeding tube, but 15 (21.7%) patients had reactive feeding tube placement for 3 months or more. A total of 9 (13.0%) patients had persistent feeding tube dependency. Univariate analysis showed that age, tracheostomy, and common terminology criteria for adverse events (CTCAE) ≥ 3 were significantly associated with reactive prolonged and persistent feeding tube dependency (all P < 0.05). In the multivariate analysis, advanced age and CTCAE ≥ 3 remained the independent factors of reactive prolonged and persistent feeding tube dependency (all P < 0.05). Feeding tube dependency was not associated with overall survival or disease-free survival (P > 0.1). Feeding tube dependency might be related to clinical factors, such as age and severe adverse events, in the patients undergoing function-preserving surgery for advanced-stage LHC.

Influence of Site, Size, Depth of Invasion and Histologic Grading on the Occurrence of Cervical Level IIb Metastasis and Extranodal Extension in Clinically N0 Neck of Patients with OSCC: A Single Center Retrospective Analysis

Background

Depth of Invasion ≥ 4 mm, T stage and primary site with more than 20% chances for occult metastasis are currently the accepted indications for elective neck dissection. Nodal metastasis decreases survival by 50%. ENE further reduces the prognosis. Dissection of level IIb lymph nodes in clinically N0 neck does not improve survival.

Methods

A total of 320 patients were evaluated. Binary and multiple logistic regression and chi-square test were used for data analysis. ROC curve with Youden's J index was used to set up a cutoff value for DOI. The predictor variables were site, size, grading and depth of invasion of primary tumor. Incidence of level IIb metastasis and ENE were the outcomes.

Results

The study revealed a significant association and risk stratification between primary tumor characteristics with the occurrence of ENE. The cutoff value for DOI predicting ENE was 12.5 mm. Tumors of the oral tongue were an independent risk factor for level IIb metastasis.

Discussion

Size of primary tumor, DOI, tumors of the mandibular alveolus and poor grading are independent risk factors for ENE. Isolated metastasis to level IIb rarely occurs in the absence of concomitant level IIa metastasis. Size, DOI and grading were significantly associated with level IIb metastasis. However, only tumors of the oral tongue were independent risk factor.

Prediction of cervical metastasis and survival in cN0 oral cavity cancer using tumour 18F-FDG PET/CT functional parameters

PURPOSE

Oral cavity squamous cell carcinoma (OCC) can spread to the neck without apparent lymphadenopathy. Pretreatment detection or prediction of occult metastasis might contribute to proper management of clinically node-negative (cN0) OCC. We examined the role of tumour quantitative 18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) measurements for predicting OCC occult metastasis and survival.

METHODS

This study included 130 cN0 OCC patients who underwent ¹⁸F-FDG PET/CT scanning and subsequent curative surgery and neck dissection. Maximum, peak, and mean standardized uptake value (SUV_max, SUV_peak, and SUV_mean), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were measured on pretreatment ¹⁸F-FDG PET/CT. Binary logistic regression was used to identify factors predicting occult cervical metastasis. Univariate and multivariate Cox proportional hazard regression were used to find factors associated with overall survival (OS).

RESULTS

Pathological cervical metastasis (pN +) was found in 29 (22.3%) patients. Age, tumour differentiation, lymphovascular invasion, and T classification were significantly associated with pN + (all P < 0.05). After adjustment for these factors, MTV and TLG independently predicted pN + (P < 0.05). Invasion depth, lymphovascular invasion, T and N classifications, and overall TNM stage were significantly associated with OS. After adjustment for these factors, SUV_max and TLG independently predicted OS (all P < 0.05). Patients with TLG > 9.3 g had a 5.7-fold increased risk of overall mortality.

CONCLUSIONS

Tumour ¹⁸F-FDG PET/CT parameters might predict occult metastasis and survival in cN0 OCC patients.

Ex vivo culture of head and neck cancer explants in cell sheet for testing chemotherapeutic sensitivity

PURPOSE

Tumor explant culture systems can mimic the in vivo tumor microenvironment, proposing as a substitute for preclinical studies for prediction of individual treatment response. Therefore, our study evaluated the potential usefulness of ex vivo tumor explants culture assembled into the cell sheets by anticancer drug screening in patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

Our model included tumor explants incorporated into cell sheet composing of epithelium and subepithelial stroma using tumor and mucosal samples obtained from the HNSCC patients who underwent surgery. Cell growth, viability, and hypoxia were measured by cell counting kit-8, live/dead assay, propidium iodide, and LOX-1 staining, and were compared among the different treatment groups with vehicle, cisplatin or docetaxel.

RESULTS

Tumor explants stably survived in the cell sheet over 10 days after explantation, whereas most of the explants in non-matrix culture became nonviable within 5-8 days with the significant daily decrease of viability. The live tissue areas of tumor explants in the cell sheet maintained over 30 days without significant changes although hypoxic cell areas gradually increased up to 5 days. Tissue viability and live cancer tissue areas significantly decreased after the treatment of cisplatin or docetaxel in the dose and time-dependent manners.

CONCLUSION

Our cell sheet-based tumor explants model might be applied to the reliable ex vivo screening for anticancer chemotherapeutics for HNSCC.

Predictors of survival and recurrence after primary surgery for cervical metastasis of unknown primary

PURPOSE

Cervical metastasis from unknown primary (CUP) is commonly classified as an advanced overall stage. P16 or human papillomavirus (HPV) positivity in metastatic lymph nodes (LN) might be associated with a favorable survival outcome of CUP. Therefore, we evaluated the prognostic values of p16 immuno-positivity in LN and other clinicopathological factors in patients with squamous cell carcinoma CUP (SCCUP).

METHODS

This study involved 83 patients who underwent therapeutic neck dissection and panendoscopic examination and biopsy for suspected CUP. P16 immunostaining and HPV typing in LN were performed in 56 patients. Cox proportional hazard regression analyses were used to identify factors associated with overall survival (OS) and disease-free survival (DFS).

RESULTS

Postoperatively, primary tumors (PT) were found in 32 (38.6%) patients, mainly (90.6%) in the oropharynx, and not found in 51 (61.4%) patients. The clinicopathological data (except for histological grade) and 5-year OS and DFS rates did not significantly differ between patients with and without PT identification (all P > 0.05). P16 positivity was associated with favorable OS and DFS outcomes in the patients with PT (P < 0.05) but not in those without PT (P > 0.1). Multivariate analyses showed that age (> 60 years) and LN ratio (≥ 0.1) were the independent predictors of OS and DFS outcomes (all P < 0.05). P16 positivity or other factors were not independent factors.

CONCLUSION

Age and LN ratio are significant risk factors of survival and recurrence after primary surgery for SCCUP. Prognostic significance of LN p16 positivity should be further studied.