Treatment outcome of combined modalities for buccal cancers: unilateral or bilateral neck radiation?

Is postoperative adjuvant therapy necessary for pT3N0 oral cavity squamous cell carcinoma?

BACKGROUND

The current NCCN guidelines advocate for the use of adjuvant radiotherapy (RT) or chemoradiotherapy (CRT) in pT3N0 oral cavity squamous cell carcinoma (OCSCC). Here, we sought to evaluate whether postoperative RT/CRT may confer a survival advantage in pT3N0 patients who lack adverse pathological features.

METHODS

A dataset of 852 pT3N0 OCSCC patients treated between 2018 and 2021 was analyzed. Patients with adverse pathological features (i.e., positive margins, margins <5 mm, lymphovascular invasion, or perineural invasion) were excluded, leaving 235 eligible patients. The cohort was further refined by omitting 12 patients who received surgery plus chemotherapy and two cases who received RT doses <5000 cGy, resulting in two study groups: surgery alone (n = 131) and surgery plus RT/CRT (n = 90).

RESULTS

Baseline characteristics were comparable between groups, except for a higher proportion of buccal subsite (p = 0.0063) and female patients (p = 0.0495) in the surgery alone group. Kaplan-Meier analyses revealed no significant differences in 4-year disease-specific survival (DSS) (84.2 % versus 85.9 %, p = 0.8834) or overall survival (OS) (75.6 % versus 84.8 %, p = 0.2376). These findings were confirmed by multivariable analyses and remained consistent after propensity score matching (n = 74 per group), with similar survival outcomes between groups (4-year DSS, 90.7 % versus 83.2 %, p = 0.4020; 4-year OS, 87.0 % versus 81.9 %, p = 0.6121) CONCLUSIONS: For patients with pT3N0 OCSCC lacking adverse pathological features, the addition of adjuvant RT/CRT does not appear to confer a survival benefit over surgery alone.

Clinical outcomes and failure patterns after postoperative radiotherapy for oral cavity squamous cell carcinoma

PURPOSE

This study aimed to assess recurrence patterns and identify the optimal dose and target volumes of postoperative radiotherapy (PORT) in patients with oral cavity squamous cell carcinoma (OSCC).

METHODS

Data of 111 patients who received PORT for OSCC between January 2010 and April 2020 were retrospectively reviewed. The median age was 68 years (range 19-88). PORT was administered as initial treatment to 63 patients and as salvage treatment for recurrent tumors to 48 patients. The median prescribed dose was 60 Gy (range 50-66) administered in 30 fractions (range 25-33).

RESULTS

Median follow-up time was 73 months (range 24-147). Overall survival (OS), progression-free survival (PFS), local control (LC), and locoregional control (LRC) at 3 years were 55.6%, 45.6%, 74.6%, and 63.1%, respectively. There were no significant differences in OS, PFS, LC, and LRC between the initially diagnosed and postoperative recurrent cases. Of 22 patients (20%) who developed regional nodal recurrences, 17 (15%) and 11 (10%) had in-field and out-of-field recurrences, respectively. Of 105 patients who received irradiation to the primary tumor bed, 24 (23%) developed recurrence at the primary site. The PFS and LC rates were significantly worse in patients receiving ≤ 56 Gy to the primary site than those receiving > 56 Gy (p = 0.016 and p = 0.032, respectively).

CONCLUSION

PORT was effective for postoperative recurrences as well as for initially diagnosed oral cavity cancer. Doses greater than 56 Gy to the primary site may be required in PORT for OSCC.

Pattern of locoregional failure in postoperative cases of locally advanced carcinoma of buccal mucosa treated with unilateral versus bilateral neck radiation: lesson learned from a basic practice setup

Background

Carcinoma of buccal mucosa forms a sizeable percentage of the diagnosed oral cavity cancers in India. There is limited data on elective treatment of the contralateral neck for well-lateralized carcinoma with no involved nodes in the contralateral neck. We conducted this study to compare locoregional control in patients treated with unilateral vs. bilateral neck irradiation.

Materials and methods

48 patients with carcinoma of buccal mucosa were selected. Patients were divided into unilateral and bilateral arms based on radiation treatment of the ipsilateral or bilateral neck. All patients received adjuvant radiation with Cobalt 60 unit. Patient-specific and follow-up data were collected from records and dosimetric data from treatment planning system (TPS). Chi-square and unpaired t-test was used to compare data between arms and Kaplan Meier plot; Cox regression was used for survival analysis.

Results

After a median follow-up of 23 months, 15 (31.3%) patients had developed disease recurrence, 8 and 7 in the unilateral and bilateral arms, respectively (p = 0.591). There was no contralateral neck failure during the follow-up period. The 2-year disease-free survival was 68.2% and 72.2% in the unilateral and bilateral arms, respectively. Among risk factors for disease recurrence, depth of invasion (DOI), delay in starting radiation and planning target volume (PTV) coverage were significant contributing factors. Cox multivariate regression suggested DOI and delay in starting radiation to be significant prognostic factors for disease-free survival (DFS).

Conclusion

Bilateral neck radiation does not provide any advantage over ipsilateral neck radiation for properly selected well lateralized buccal mucosal squamous cell carcinoma. Ipsilateral neck radiation facilitates better sparing of organs at risk.

Nomogram predicting long-term overall and cancer-specific survival of patients with buccal mucosa cancer

BACKGROUND

Few models about the personalized prognosis evaluation of buccal mucosa cancer (BMC) patients were reported. We aimed to establish predictive models to forecast the prognosis of BMC patients.

METHODS

The complete clinicopathological information of BMC patients from the surveillance, epidemiology and end results program was collected and reviewed retrospectively. Two nomograms were established and validated to predict long-term overall survival (OS) and cancer-specific survival (CSS) of BMC patients based on multivariate Cox regression survival analysis.

RESULTS

1155 patients were included. 693 and 462 patients were distributed into modeling and validation groups with 6:4 split-ratio via a random split-sample method. Based on the survival analysis, independent prognostic risk factors (variables that can be used to estimate disease recovery and relapse chance) influencing OS and CSS were obtained to establish nomograms. Then, we divided the modeling group into high- and low-risk cohorts. The low-risk cohort had improved OS and CSS compared to the high-risk cohort, which was statistically significant after the Log-rank test (p < 0.05). Furthermore, we used the concordance index (C-index), calibration curve to validate the nomograms, showing high accuracy. The decision curve analyses (DCA) revealed that the nomograms had evident clinical value.

CONCLUSIONS

We constructed two credible nomogram models, which would give the surgeons reference to provide an individualized assessment of BMC patients.

Efficacy of Postoperative Unilateral Neck Irradiation in Patients with Buccal Mucosa Squamous Carcinoma with Extranodal Extension: A Propensity Score Analysis

Unilateral radiotherapy (RT) as a postoperative treatment for multiple ipsilateral lymph node (LN) metastases remains controversial. We investigated the efficacy of postoperative unilateral RT for buccal mucosa squamous cell carcinoma (BMSCC) with extranodal extensions (ENEs). We retrospectively reviewed the clinical records of 186 patients with ENE+ BMSCC who received postoperative RT during 1997-2016. Propensity score matching was used to establish comparable cohorts. The endpoints were contralateral nodal control (CLNC), overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS), local control (LC), and regional control (RC). After matching, 123 patients were selected for analysis; 45 (36.6%) and 78 (63.4%) patients underwent unilateral and bilateral RT, respectively. The median follow-up was 36.27 months. The survival outcomes in the unilateral and bilateral RT groups were similar: 3-year CLNC (85.6% vs. 89.1%, p = 0.748), OS (53.2% vs. 57.4%, p = 0.229), DFS (46.5% vs. 48.6%, p = 0.515), DMFS (70.7% vs. 72.0%, p = 0.499), LC (78.0% vs. 75.6%, p = 0.692), and RC (79.9% vs. 76.2%, p = 0.465). On multivariable Cox regression analysis, unilateral and bilateral RT showed comparable outcomes; the number of ENEs ≥ 4 was the only significant prognostic factor for all clinical outcomes. Using decision tree analysis, we classified our patients to have a low, intermediate, or high risk of contralateral failure based on three factors: number of ENEs, margin status, and tumor stage. In conclusion, postoperative unilateral RT did not worsen outcomes in patients with ENE+ BMSCC in this cohort. The decision tree model may assist physicians in optimizing and tailoring radiation fields.

A Rational Approach to Unilateral Neck RT for Head and Neck Cancers in the Era of Immunotherapy

Radiotherapy plays an important role in the definitive and adjuvant treatment of head and neck squamous cell carcinoma (HNSCC). However, standard courses of radiation therapy may contribute to the depletion of circulating lymphocytes and potentially attenuate optimal tumor antigen presentation that may be detrimental to the efficacy of novel immunotherapeutic agents. This review explores the advantages of restricting radiation to the primary tumor/tumor bed and ipsilateral elective neck as it pertains to the evolving field of immunotherapy.

Adjuvant contralateral neck irradiation for oral cavity cancer - A systematic review and meta-analysis

INTRODUCTION

Whether contralateral neck irradiation should be administered for oral cavity cancer is a critical question because patients receiving bilateral neck irradiation experience more adverse effects. Patients not receiving contralateral neck irradiation are at risk of contralateral neck recurrence of oral cavity cancer MATERIALS AND METHODS: Meta-analysis and subgroup analysis were performed for the rates of contralateral neck recurrence of oral cavity cancer in patients receiving no contralateral neck radiation. We aimed to identify the patient group suitable for contralateral neck radiotherapy omission. The PRISMA guideline was used for this study. We extracted data including the first author, country, sample size, numbers of patients receiving ipsilateral neck radiotherapy and experiencing contralateral neck recurrence, participant characteristics, and details of cancer types RESULTS: The rate of contralateral neck recurrence is extremely low, 3.4% (95% confidence interval: 2.2%-5.4%). Isolated contralateral neck recurrence occurred in 18 of 524 patients receiving radiotherapy to the primary tumor site with or without ipsilateral irradiation. The subgroup analysis was conducted to investigate pathological lymph node stage and subsite. Subgroup analysis showed that the N2-3 group was more likely to exhibit recurrence in contralateral neck than the N0-1 group was (14.4% versus 1.5%, p = 0.0008). In addition, the contralateral neck recurrence rate was 6.3% (95% CI = 2.3%-13.1%) and 2.8% (95% CI = 1.5%-4.8%), in the tongue cancer patient group and the non-tongue cancer patient group, respectively. Meta-regression showed that the rate of contralateral recurrence was not different between both groups (p = 0.08). Only 2 exhibited isolated contralateral neck recurrence (5.1%) in pN0-1 tongue cancer patient. Most of them (>90%) are lateralized.

CONCLUSION

In conclusion, the omission of contralateral irradiation is reasonable in pN0-1, well lateralized oral cavity cancer.

Contralateral lymph node recurrence rate and its prognostic factors in stage IVA-B well-lateralized oral cavity cancer

PURPOSE

To evaluate the contralateral lymph node recurrence rate (clLNRR) of stage IVA to IVB well-lateralized oral cavity cancer. To evaluate the risk factors of clLNRR.

MATERIALS AND METHODS

Pathologic stage IVA-B squamous cell carcinoma of oral cavity, originating from buccal mucosa, gingiva, or retromolar trigone were retrospectively recruited. Those who did not receive definitive surgery, with previous cancer history, or with contralateral nodal metastasis at diagnosis were excluded.

RESULTS

From 2010 to 2017, 120 cases were enrolled, including 103 pT4 and 38 pN2. Thirty-one patients underwent contralateral neck dissection, and 18 had contralateral elective nodal irradiation. After median follow up of 35.1 months, the 3-year clLNRR was 15.7% (95% CI: 8.8 - 22.6%) as first event and was 17.1% (95% CI: 9.8 - 24.4%) for overall recurrences. The 3-year disease-free survival and overall survival were 52.8% and 63.1%, respectively. In multivariate analysis, positive nodal metastasis, gingival origin, and perineural invasion were associated with significantly higher clLNRR. Nodal metastasis was the strongest prognostic factor for clLNRR (pN1, HR: 17.1, p = 0.010; pN2, HR: 16.7, p = 0.004, comparing to pN0). The 3-year clLNRR were 2.9% for pN0 (n = 71, 95% CI: 0 - 6.8%), 37.7% for pN1 (n = 11, 95% CI: 8.3 - 67.1%), and 38.4% for pN2 (n = 38, 95% CI: 19.2 - 57.6%). Advanced T classification, elective contralateral neck dissection, and contralateral nodal irradiation did not have significant impact on clLNRR.

CONCLUSIONS

Positive homolateral nodal metastasis, gingival origin, and perineural invasion were risk factors correlated with significantly higher clLNRR. For patient without nodal metastasis, the clLNRR was low and elective contralateral neck management might be safely omitted. For patients with homolateral nodal disease, the contralateral nodal recurrence was not unusual. The optimal treatment for these high risk patients warrant further research.

Patterns of failure and clinical outcomes of post-operative buccal mucosa cancers treated with adjuvant ipsilateral radiotherapy

Purpose

Adjuvant radiotherapy (RT) in buccal mucosa cancers is guided by histopathological factors. The decision to treat ipsilateral or bilateral draining lymph node is on physician discretion and guidelines do not have a defined indication regarding this. We aimed to analyze the failure patterns and survival in buccal mucosa cancers treated with adjuvant ipsilateral RT.

Materials and Methods

One hundred sixteen cases of post-operative buccal mucosa cancers—pT3 or more, node positive, close margins (1–5 mm), lymphovascular invasion positive, perineural invasion positive, depth of invasion >4 mm—treated with RT to primary and ipsilateral nodes from May 2013 to May 2019 were retrospectively analyzed. Patients were treated to a dose of 60–66 Gy (44 Gy in the first phase and a coned down boost of 16–22 Gy in the second phase) with three-dimensional conformal radiotherapy on a linear accelerator. Primary end point was to assess control rates and secondary end point was to evaluate the overall survival (OS) and disease-free survival (DFS) outcomes.

Results

Median age was 46 years with male; female ratio of 110:6. The edition of the American Joint Committee on Cancer stage distributions were I (3.4%), II (34.4%), III (24.1%), and IV (37.9%). At a median follow-up of 22 months, crude rates of local failure, regional failure, and contralateral neck failure were 9.4%, 10.3%, and 3.4%, respectively. The 2-year contralateral neck control rate was 94.9%. Pathological positive node portended poorer OS (86.6% vs. 68.6%; p = 0.015) and DFS (86.5% vs. 74.9%; p = 0.01).

Conclusion

Incidence of contralateral recurrence with ipsilateral irradiation in buccal mucosa cancers is low with descent survival outcomes, particularly in node negative cases.

Preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil for oral squamous cell carcinoma

The objectives of this study were to evaluate survival in 141 patients with stage II-IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.

Evaluating the effectiveness of adjuvant radiotherapy in addition to surgery versus surgery alone at improving oncologic outcomes for early stage buccal carcinoma: a systematic review

OBJECTIVE

To systematically review the evidence to evaluate oncologic outcomes for patients with early stage buccal squamous cell carcinoma treated with surgery versus surgery and adjuvant radiation therapy.

DATA SOURCES

Ovid MedLine, EMBASE, Google Scholar, PubMed.

REVIEW METHODS

The primary purpose was to perform a systematic review to determine the published literature comparing oncologic outcomes of patients with early stage (Stages I&II) buccal mucosal squamous cell carcinoma, treated with surgical resection alone versus surgery plus adjuvant radiation therapy. Oncologic outcomes of interest were overall survival, locoregional recurrence, and disease specific survival. The secondary aim was to perform a meta-analysis to quantitively compare and summarize the data on oncologic outcomes between treatments.

RESULTS

A total of 1457 studies were screened and five retrospective cohort studies (n = 733 patients) were eligible for quantitative analysis. Overall study quality was moderate to high. Pooled relative risk ratios using a fixed effects model did not reveal any statistically significant difference in overall survival (p = 0.70) or locoregional recurrence rates (p = 0.72) in Stage I and II disease.

CONCLUSIONS

These results demonstrate there is sparse evidence comparing oncologic outcomes for early stage buccal squamous cell carcinoma treated with surgery alone versus surgery and adjuvant radiation therapy. Our findings based on a limited body of evidence suggest no obvious benefit in the addition of adjuvant radiation therapy, however robust randomized trials are warranted to reach firm conclusions.

Multi-center retrospective study of the prognosis and treatment outcomes of Japanese oral squamous cell carcinoma patients with single lymph node metastasis and extra nodal extension

BACKGROUND

Oral squamous cell carcinoma (OSCC) containing single lymph node metastasis (pN1) with extra nodal extension (ENE) is a rare clinical situation. Therefore, it is unclear whether pN1 with ENE is at high risk of recurrence among the OSCC population, or whether postoperative radiotherapy (RT)/concomitant chemoradiotherapy (CCRT) is effective in these cases.

OBJECTIVES

The purpose of this retrospective study was to investigate the prognosis and compare between no postoperative therapy and postoperative RT/CCRT in pN1 with ENE OSCC patients.

METHODS

Clinicopathological data and treatment modalities were investigated. The evaluated endpoints were overall survival (OS) and type of recurrence.

RESULTS

The 3-year cumulative OS rates for the pN1 only, multiple lymph node metastasis (MLM) only, ENE + MLM, and ENE + pN1 groups were 77.2%, 66.8%, 43.3%, and 66.6%, respectively. In the ENE + pN1 group, the most common cause of death in the surgery only group was from regional failure. The surgery + RT/CCRT group was associated with better disease-specific survival and OS rates than the surgery only groups (P < 0.05).

CONCLUSIONS

The prognosis of ENE + pN1 was not as poor as that of ENE + MLM, although both these groups feature ENE. Adjuvant therapy (RT/CCRT) after surgery is recommend for cases of ENE + pN1.

Postoperative concomitant chemoradiotherapy improved treatment outcomes of patients with oral cavity cancer with multiple-node metastases but no other major risk factors

Purpose

To investigate the results of postoperative radiotherapy (PORT) for the treatment of pathologic N2b/c squamous cell carcinoma of the oral cavity (OSCC).

Materials and Methods

This study reviewed cancer registry data collected in our hospital from 1998 to 2009 with the following inclusion criteria: primary OSCC, treatment with radical surgery, and multiple nodal metastases. Patients who had extracapsular spreading of the lymph node metastases or positive resection margins or who refused to undergo PORT were excluded. The prescribed dose of PORT was 60–66 Gy. Concurrent chemotherapy was optional. Patient characteristics, treatment parameters and clinical outcome were recorded. The primary end point was overall survival, and the secondary endpoint was disease status.

Results

There were 138 eligible cases, and the median follow-up period was 35 months. The 3-year overall survival rate was 56%. Univariate analysis revealed that pathologic T4 status (pT4), bone marrow invasion, and lymphatic invasion were significantly correlated with poor outcome (p<0.05). Multivariate analysis showed that pT4, lymphatic invasion, and the no concurrent chemotherapy were independent poor prognostic factors (p<0.05). Fifty-four patients had tumor recurrence. The 3-year recurrence-free survival rate was 59%. Skin invasion, pT4, and bone marrow invasion were correlated with poor prognosis in the univariate analysis (p<0.05). Only pT4 (p<0.01) and no concurrent chemotherapy (p = 0.03) were independently correlated with poor recurrence-free survival.

Conclusion

For OSCC patients with multiple-node metastases without extracapsular spreading or positive resection margins, PORT without concurrent chemotherapy correlated to inferior outcome. Multiple lymph node metastases might be considered an indication for concurrent chemotherapy.

Sequential therapy of advanced buccal mucosa squamous cell carcinoma: three-year outcome

PURPOSE

Squamous cell carcinoma (SCC) of the buccal mucosa is aggressive and requires multimodal treatment. The objective of this study was to evaluate the outcome of sequential therapy (neoadjuvant therapy plus surgery plus radiotherapy) in advanced buccal SCC and explore the prognostic factors.

PATIENTS AND METHODS

In this retrospective cohort study, patients with advanced buccal cancer who received neoadjuvant chemotherapy (cisplatin, docetaxel, and 5-fluorouracil) followed by surgery and radiotherapy in the authors' department were reviewed. The outcomes of chemotherapy and surgery were analyzed. Overall survival (OS) and disease-free survival (DFS) were calculated using the Kaplan-Meier method. The prognostic values of age, gender, histologic grade, lymph node status, tumor stage, pathologic response, and adverse pathologic features were explored using the log-rank test and the Cox regression model.

RESULTS

From 2008 to 2011, data from 22 patients were analyzed. The overall response rate of chemotherapy was 72.7%. The pathologic complete or partial response rate was 40.9%. The median follow-up was 36 months. The 2-year DFS and OS rates were 63.3% and 67.2%, respectively. Male and younger patients showed an association with poor outcome. Multivariate analysis showed that gender was a predictive factor with respect to DFS and OS (P = .023 and .014, respectively).

CONCLUSION

Sequential therapy (neoadjuvant therapy plus surgery plus radiotherapy) tends to be effective for advanced buccal cancer. Female patients have better survival.

Squamous cell carcinoma of the buccal mucosa: Analysis of clinical presentation, outcome and prognostic factors

Squamous cell carcinoma (SCC) of the buccal mucosa is a common malignancy in Southeast Asia. The purpose of this study was to present our clinical experience with buccal SCC over a period of 7 years and to analyze the factors associated with surgical outcome. We conducted a retrospective review on 67 buccal SCC patients (between September, 2005 and May, 2011) with tumors restricted to or originating from the buccal mucosa. In a univariate model, nodal stage, degree of tumor differentiation and composite resection were associated with recurrence, while in a multivariate model, the degree of differentiation was the only factor affecting locoregional control. In a survival analysis, recurrence, nodal stage and degree of differentiation were considered as significant factors. Buccal SCC is an aggressive malignant tumor and the degree of differentiation is the most significant factor affecting prognosis and survival. An adequate systemic treatment is required in the case of poorly differentiated tumors. Neck dissection (ND) exerts a positive effect on the locoregional control of buccal SCC staged as cT1-2N0. In the case of identification of positive lymph nodes during surgery, postoperative radiation is recommended in order to improve locoregional control.

GP96 is over-expressed in oral cavity cancer and is a poor prognostic indicator for patients receiving radiotherapy

Background

Oral cavity cancers (ORC) are the most common cancers, and standard treatment is radical surgery with postoperative radiotherapy. However, locoregional failure remains a major problem, indicating radioresistance an important issue. Our previous work has shown that GP96 contributed to radioresistance in nasopharyngeal and oral cancer cell lines. In this study, we determined clinical significance of GP96 in ORC by evaluation of GP96 expression and its association with disease prognosis in patients receiving radiotherapy

Methods

Total of 79 ORC patients (77 males, median age: 48 years old) receiving radical surgery and postoperative radiotherapy between Oct 1999 and Dec 2004 were enrolled. Patients in pathological stages II, III and IV were 16.5%, 16.5% and 67%, respectively. For each patient, a pair of carcinoma tissue and grossly adjacent normal mucosa was obtained. GP96-expression was examined by western blot analysis, and the association with clinicopathological status was determined.

Results

Three-year locoregional control (LRC), distant metastasis-free survival (DMFS), disease-specific survival (DSS) and overall survival (OS) rates were 69%, 79%, 63% and 57%, respectively. We found that 55 patients (70%) displayed GP96-overexpression in the tumor tissue, which correlated with a higher pN stage (p = 0.020) and tumor depth (> 10 mm) (p = 0.045). Nodal extracapsular spreading (ECS) and GP96-overexpression predicted adverse LRC (p = 0.049 and p = 0.008). When stratified by nodal ECS, the adverse impact of GP96 remained significant in three-year LRC (p = 0.004). In multivariate analysis, GP96-overexpression was also an independent predictor of LRC, DSS and OS (p = 0.018, p = 0.011 and p = 0.012).

Conclusion

GP96 may play roles in radioresistance which attributes to tumor invasiveness in oral cancer patients receiving radiotherapy. GP96 may serve as a novel prognostic marker of radiotherapy. However, further independent studies are required to validate our findings in a larger series.

Prognostic factors in patients with buccal squamous cell carcinoma: 10-year experience

PURPOSE

Squamous cell carcinoma (SCC) of the buccal mucosa accounts for 23% to 37% of all intraoral cancer cases in Taiwan. Because of the high recurrence rate and invasive tumor behavior, the prognosis is generally poor. The aim of this study was to evaluate the prognostic significance of clinicopathologic factors on survival rates for patients with buccal SCC in a medical center in central Taiwan.

MATERIALS AND METHODS

Between March 1995 and December 2002, patients admitted to hospital and diagnosed as having buccal SCC were enrolled in the study. There were 415 patients (406 men and 9 women) 25 to 84 years old (mean age, 51.1 ± 11.4 years). The chart records were retrospectively reviewed. Relevant clinical features in each patient, such as primary tumor size, tumor stage, initial treatment modalities, surgical margin status, cervical nodal metastasis status, and histopathologic grade, were compared for survival analysis.

RESULTS

Three hundred ninety-four patients received surgical intervention. Univariate analysis of relevant prognostic factors showed that positive surgical margin, positive cervical nodal metastasis, positive extracapsular spread, larger tumor, and advanced tumor stage were associated with poor prognosis. Multivariate analysis identified the factors that independently influenced the survival rate as advanced stage disease (stage III: relative risk [RR], 3.09; P = .006; stage IV: RR, 4.64; P < .001), positive surgical margin (RR, 2.02; P = .001), and extracapsular spread of cervical lymph node metastasis (RR, 6.89; P < .001).

CONCLUSIONS

This study represents the largest series in the literature and highlights the importance of tumor stage, surgical margin status, and extracapsular spread of cervical nodal metastasis as the most important prognostic factors in patients with buccal SCC.

Marginal recurrences after selective targeting with intensity-modulated radiotherapy for oral tongue cancer

BACKGROUND

No universal consensus of optimal radiation target coverage for oral tongue cancer exists, and there is wide variability in practice. Some centers use intensity-modulated radiotherapy (IMRT) to selectively target only certain regions at risk while sparing others; however, patterns of failure after such selective targeting are rarely reported.

METHODS AND RESULTS

We critically examined the location of failure in 4 patients with stage III to IV oral tongue cancer who presented to our department with locoregional recurrence after receiving IMRT with selective radiation targeting at outside institutions. All 4 patients' cancer recurred marginally in regions that were not initially targeted, whereas the regions would have been targeted if comprehensive IMRT targeting had been used. The median time to recurrence was short (3.9 months; range, 1.2-10.1 months).

CONCLUSION

This case series highlights the occurrence of marginal failures after selective targeting with IMRT for oral tongue cancer and cautions against this practice unless further supporting evidence becomes available.

Buccal mucosa carcinoma: surgical margin less than 3 mm, not 5 mm, predicts locoregional recurrence

Background

Most treatment failure of buccal mucosal cancer post surgery is locoregional recurrence. We tried to figure out how close the surgical margin being unsafe and needed further adjuvant treatment.

Methods

Between August 2000 and June 2008, a total of 110 patients with buccal mucosa carcinoma (25 with stage I, 31 with stage II, 11 with stage III, and 43 with Stage IV classified according to the American Joint Committee on Cancer 6^th edition) were treated with surgery alone (n = 32), surgery plus postoperative radiotherapy (n = 38) or surgery plus adjuvant concurrent chemoradiotherapy (n = 40).

Main outcome measures: The primary endpoint was locoregional disease control.

Results

The median follow-up time at analysis was 25 months (range, 4-104 months). The 3-year locoregional control rates were significantly different when a 3-mm surgical margin (≤3 versus >3 mm, 71% versus 95%, p = 0.04) but not a 5-mm margin (75% versus 92%, p = 0.22) was used as the cut-off level. We also found a quantitative correlation between surgical margin and locoregional failure (hazard ratio, 2.16; 95% confidence interval, 1.14 - 4.11; p = 0.019). Multivariate analysis identified pN classification and surgical margin as independent factors affecting disease-free survival and locoregional control.

Conclusions

Narrow surgical margin ≤3 mm, but not 5 mm, is associated with high risk for locoregional recurrence of buccal mucosa carcinoma. More aggressive treatment after surgery is suggested.

Tongue and buccal mucosa carcinoma: is there a difference in outcome?

BACKGROUND

We sought to determine the differences in clinical outcome of tongue and buccal carcinomas.

METHODS

Five-year locoregional control, distant metastasis, and survival rates were examined in 456 patients with tongue cancer and 407 patients with buccal cancer.

RESULTS

Five-year rates for patients with tongue and buccal carcinomas were as follows: local control, 85% and 87% (P = 0.9366); neck control, 81% and 87% (P = 0.0304); distant metastasis, 8% and 14% (P = 0.0052); disease-free survival, 70% and 72% (P = 0.9978); disease-specific survival, 79% and 78% (P = 0.2435), respectively. After stratification according to pathological lymph node status, patients with buccal cancer and pN0/pNx disease (without neck dissection) had a higher 5-year neck control rate than those with tongue cancer (93% versus 86%, P = 0.0115). In contrast, buccal cancer with pN+ disease had a higher 5-year distant metastasis rate compared with tongue cancer (30% versus 18%, P = 0.0231). In pN0/pNx subjects, neck control was predicted by perineural invasion and the absence of neck dissection in tongue cancer, and by poor differentiation in buccal cancer. In pN+ patients, distant metastases were predicted by pT3-4 disease, age at onset ≤40 years, poor differentiation, and pN+ ≥ 5 nodes in tongue cancer, and by poor differentiation and pN+ ≥ 5 nodes in buccal cancer.

CONCLUSIONS

There are significant differences in the failure pattern of tongue and buccal carcinomas. Prognostic models for these malignancies should allow stratification of patients for a risk-adapted approach to treatment.

Transcriptome profiling and network pathway analysis of genes associated with invasive phenotype in oral cancer

The aim of this study was to clarify relevant alterations of gene expression associated with the invasive phenotype of oral cancer. To reduce heterogeneity and to obtain data on genes specifically involved in invasive mechanism, we established a highly invasive ORC subline through in vitro Matrigel invasion method. Affymetrix microarrays were used for transcriptome profiling between parental and the highly invasive subline. Seventy-nine genes were differentially expressed at least 2-fold, including 38 up-regulated and 41 down-regulated. After analyzing the microarray data by MetaCore algorithm, a total of 12 regulatory pathways were found to be associated with invasive phenotype (p<0.001). Two functional pathways were most significant: the cell adhesion through extracellular matrix remodeling (p=4.964e-06), and MHC-class-I mediated antigen presentation (p=9.843e-05). To shed more light on the biological functions of invasiveness, two genes highly over-expressed in the invasive subline, Cyr61 and CD44 were further validated. RNAi knockdown of these two genes led to significant suppression of cell growth (32% and 31%, respectively at day 3), cell migration (45% and 96%, respectively at 24 h), and cell invasion (83% and 87%, respectively at day 3). These results suggested important roles of these genes in regulating invasive phenotype, and demonstrated the confidence of this study design in the search of invasive associated genes. The identified pathways associated with invasion mechanism may be novel targets for manipulation of the cancer behavior with consequences on treatment outcome.

Balancing risk and reward in target delineation for highly conformal radiotherapy in head and neck cancer

The therapeutic index of highly conformal radiotherapy (RT) depends on adequate selection and delineation of the gross tumor volumes, the clinical target volumes, and the tissues and organs whose sparing is likely to gain clinical benefit. Decisions about target and tissue selection and delineation affect the balance of reward and the risk of highly conformal RT. Some of these issues relating to head and neck cancer, including target delineation after tumor shrinkage by induction chemotherapy or at midradiotherapy, are discussed in this article.

Risk stratification of patients with oral cavity squamous cell carcinoma and contralateral neck recurrence following radical surgery

Clinical outcome of patients with oral cavity squamous cell carcinoma (OSCC) and contralateral neck recurrence (CLNR) remains poor. We sought to identify factors associated with CLNR and incorporate them into a risk stratification scheme. Between January 1996 and June 2006, a total of 913 consecutive OSCC patients treated by radical surgery were investigated. Postoperative adjuvant therapy was performed in the presence of pathological risk factors. The duration of follow-up was at least 24 months in all surviving patients. Outcome measures were the 5-year CLNR and overall survival rates. In the entire study cohort, the 5-year CLNR rate was 7% (55/913). Specifically, it was 18% (17/132) in patients with local recurrence (LR), and 5% (38/781) in those without (P = 0.0002). In multivariate analysis, extracapsular spread (ECS) was the only independent risk factor for CLNR in patients with LR. Tumor subsite, poor differentiation, and presence of pN + disease were significant predictors of CLNR in patients without LR. We identified two groups of patients with high CLNR rates. The first group consisted of patients with ECS at the initial diagnosis and LR. The second group consisted of subjects with tongue cancer without LR harboring at least two risk factors. We conclude that, in patients who achieved local control, postoperative contralateral neck treatment is recommended for subjects with tongue cancer and at least two risk factors. Once LR occurs, contralateral neck treatment is recommended in patients with ECS.