Li-Yu Lee

Prospective Study of [18F]Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography and Magnetic Resonance Imaging in Oral Cavity Squamous Cell Carcinoma With Palpably Negative Neck

PURPOSE To assess the clinical usefulness of [(18)F]fluorodeoxyglucose positron emission tomography ([18F]FDG PET) as well as computed tomography (CT) or magnetic resonance imaging (MRI) in oral squamous cell carcinoma (SCC) patients with palpably negative neck. PATIENTS AND METHODS In total, 134 oral SCC patients with palpably negative neck were prospectively evaluated with [18F]FDG PET, CT/MRI, and their visual correlation. Histopathologic analysis was used as the gold standard for assessment of these imaging techniques. RESULTS Thirty-five (26.1%) of our 134 patients were found to have neck metastases. On a level-by-level basis, the sensitivity of [18F]FDG PET for nodal metastases was two-fold higher than that of CT/MRI (41.2% v 21.6%, respectively; P = .021). Visual correlation of [(18)F]FDG PET and CT/MRI yielded slightly higher sensitivity and specificity than [18F]FDG PET alone (47.1% v 41.2%, P = .25; 98.0% v 96.8%, P = .125, respectively). On a patient-by-patient basis, the sensitivity of [18F]FDG PET for neck metastases was 51.4% and increased to 57.1% after visual correlation with CT/MRI. The probabilities of occult neck metastasis after using [(18)F]FDG PET were 6.7% in T1 tumors, 10.8% in T2 tumors, 13.3% in T3 tumors, and 25% in T4 tumors and decreased to 3.3% in T1 tumors and to 9.2% in T2 tumors after visual correlation with CT/MRI. CONCLUSION [(18)F]FDG PET was superior to CT/MRI for detecting palpably occult neck metastasis of oral SCC. Because [(18)F]FDG PET could reduce the probability of occult neck metastasis to less than 15% in T1 to T3 tumors, it should be indicated for evaluation of these subpopulations.

Analysis of risk factors for distant metastases in squamous cell carcinoma of the oral cavity

The number of patients with oral cavity squamous cell carcinoma (OSCC) is increasing. Because the characteristics of patients with OSCC who develop distant metastases (DM) remain uncertain, the authors analyzed potential risk factors.

DSG3 is overexpressed in head neck cancer and is a potential molecular target for inhibition of oncogenesis

To identify genes that could potentially serve as molecular therapeutic markers for human head and neck cancer (HNC), we employed differential display analysis to compare the gene expression profiles between HNC and histopathologically normal epithelial tissues. Using reverse transcription–polymerase chain reaction and Western blot analysis, desmoglein 3 (DSG3) was identified as being differentially expressed at both the RNA and protein levels. Of 56 patients assayed, 34 (61%) had overexpression of DSG3, which correlated statistically with T stage (P=0.009), N stage (P=0.047), overall stage (P=0.011), tumor depth (P=0.009) and extracapsular spread in lymph nodes (P=0.044), suggesting that DSG3 participates in carcinogenesis of HNC. Consistent with the clinical findings, inhibition of DSG3 by RNA interference (RNAi) significantly reduced cell growth and colony formation to 57–21% in three HNC cell lines. Use of an in vitro wound healing and Matrigel invasion assays, we found that cell migration and invasive ability were also inhibited to 30–48% in three cell lines tested. An in vivo xenograft study showed that administration of DSG3-RNAi plasmid significantly inhibited tumor growth for 2 months in BALB/C nude mice. In conclusion, DSG3 is identified overexpressed in HNC, with the degree of overexpression associated with clinicopathologic features of the tumor. Inhibition of DSG3 significantly suppresses carcinogenic potential in cellular and in vivo animal studies. These findings suggest that DSG3 is a potential molecular target in the development of adjuvant therapy for HNC.

Surgical outcome of T4a and resected T4b oral cavity cancer.

The American Joint Committee on Cancer (AJCC) 2002 staging system (AJCC 2002) suggested that squamous cell carcinoma of the oral cavity (OSCC) with T4b is unresectable. The current retrospective results show that selected T4b patients were resectable with favorable outcomes.

Human papillomavirus-16 infection in advanced oral cavity cancer patients is related to an increased risk of distant metastases and poor survival.

Background Human papillomavirus (HPV) is an oncogenic virus causing oropharyngeal cancers and resulting in a favorable outcome after the treatment. The role of HPV in oral cavity squamous cell carcinoma (OSCC) remains ambiguous. Objective This study aimed to examine the effect of HPV infection on disease control among patients with OSCC following radical surgery with radiation-based adjuvant therapy. Patients and Method We prospectively followed 173 patients with advanced OSCC (96% were stage III/IV) who had undergone radical surgery and adjuvant therapy between 2004 and 2006. They were followed between surgery and death or up to 60 months. Surgical specimens were examined using a PCR-based HPV blot test. The primary endpoints were the risk of relapse and the time to relapse; the secondary endpoints were disease-free survival, disease-specific survival, and overall survival. Results The prevalence of HPV-positive OSCC was 22%; HPV-16 (9%) and HPV-18 (7%) were the genotypes most commonly encountered. Solitary HPV-16 infection was a poor predictor of 5-year distant metastases (hazard ratio, 3.4; 95% confidence interval, 1.4–8.0; P = 0.005), disease-free survival (P = 0.037), disease-specific survival (P = 0.006), and overall survival (P = 0.010), whereas HPV-18 infection had no impact on 5-year outcomes. The rate of 5-year distant metastases was significantly higher in the HPV-16 or level IV/V metastasis group compared with both the extracapsular spread or tumor depth ≥11-mm group and patients without risk factors (P<0.001). Conclusions HPV infections in advanced OSCC patients are not uncommon and clinically relevant. Compared with HPV-16-negative advanced OSCC patients, those with a single HPV-16 infection are at higher risk of distant metastases and poor survival despite undergoing radiation-based adjuvant therapy and require a more aggressive adjuvant treatment and a more thorough follow-up.

Salvage therapy in relapsed squamous cell carcinoma of the oral cavity: How and when?

Relapse of tumors in patients with oral cavity squamous cell carcinoma (OSCC) is associated with a poor prognosis. In addition, salvage therapy may be a significant source of morbidity in patients with relapsing OSCC. The objective of the current study was to determine prognostic factors that predict which patients may benefit from such treatment.

Differentially expressed genes in radioresistant nasopharyngeal cancer cells: gp96 and GDF15

Radiotherapy is the major treatment modality for nasopharyngeal cancer (NPC), but in some cases, the disease is radioresistant. We designed this study to identify genes that may be involved in this resistance. We first established two radioresistant subclone cell lines derived from NPC parental cell lines (NPC-076 and NPC-BM1) by treating the cells with four rounds of sublethal ionizing radiation. cDNA microarray analysis was then done, comparing the two resistant cell lines with their corresponding parental cell lines. Seven genes were found to be up-regulated in radioresistant subclones, including gp96 and GDF15, which had shown highest overexpressions. We constructed small interfering RNA plasmids (gp96si and GDF15si) and transfected them into NPC cells to knock down these genes and examine whether this changed their response to radiation. Both gp96si and GDF15si transfectants had radiation-induced growth delay and reduction in colonogenic survival compared with control cells. Knockdown of either gp96 or GDF15 increased the proportion of the cells in G2-M phase, the most radiosensitive phase of the cell cycle. We have therefore identified at least two genes, gp96 and GDF15, involved in radioresistance of NPC cell lines and showed that knockdown of the genes enhances radiosensitivity. [Mol Cancer Ther 2007;6(8):2271–9]

Pretreatment Primary Tumor SUVmax Measured by FDG-PET and Pathologic Tumor Depth Predict for Poor Outcomes in Patients With Oral Cavity Squamous Cell Carcinoma and Pathologically Positive Lymph Nodes

PURPOSE The pathologic tumor depth is an independent prognosticator for local control (LC) and survival in patients with oral cavity squamous cell carcinoma (OSCC). We sought to investigate the prognostic value of the preoperative maximal standardized uptake value (SUVmax) at the primary tumor in OSCC patients with pathologically positive lymph nodes. METHODS AND MATERIALS A total of 109 OSCC patients with pathologically positive lymph nodes were investigated. All patients underwent 2-deoxy-2[(18)F]fluoro-d-glucose-positron emission tomography within 2 weeks before surgery and neck dissection. All patients were followed for >or=24 months after surgery or until death. The optimal cutoff value for the primary tumor SUVmax was selected according to the 5-year LC rate. Independent prognosticators were identified by Cox regression analysis. RESULTS The median follow-up for all patients was 26 months (39 months for surviving patients). A cutoff SUVmax of 19.3 provided the greatest prognostic information for the 5-year LC rate (55% vs. 88%, p = 0.0135). A tumor depth >or=12 mm appeared to be the most appropriate cutoff for predicting the 5-year LC rate (76% vs. 95%, p = 0.0075). A scoring system using the primary tumor SUVmax and tumor depth was formulated to define distinct prognostic groups. Patients with both a SUVmax of >or=19.3 and tumor depth of >or=12 mm (n = 8) had significantly poorer 5-year LC, 5-year disease-free, 5-year disease-specific, and 5-year overall survival rates compared with the other patient groups. CONCLUSION The combination of the primary tumor SUVmax (>or=19.3) and pathologic tumor depth (>or=12 mm) identified a subgroup of OSCC patients at greatest risk of poor LC and death.

Neck dissection field and lymph node density predict prognosis in patients with oral cavity cancer and pathological node metastases treated with adjuvant therapy

Pathological lymph node metastases (pN+) are an established prognostic factor in oral cavity squamous cell carcinoma (OSCC). We retrospectively examined the prognostic significance of lymph node (LN) density in pN+ OSCC patients who underwent neck dissection (ND) and postoperative adjuvant therapy. We examined 309 pN+ patients who underwent levels I-III ND and 148 pN+ patients treated with levels I-V ND. The 5-year control and survival rates served as the main outcome measures. The 5-year rates for patients treated with levels I-III and I-V NDs were as follows: local control, 79%, 74% (p=0.0630); neck control, 81%, 68% (p=0.0014); distant metastasis, 21%, 36% (p=0.0003); disease-free survival (DFS), 59%, 43% (p=0.0001); disease-specific survival (DSS), 66%, 46% (p<0.0001); and overall survival (OS), 49%, 37% (p=0.0048), respectively. Multivariate analysis demonstrated that an LN density ≥0.16 was an independent prognostic factor for 5-year neck control (all data presented as p, hazard ratio [95% confidence interval]) (0.003, 2.691 [1.412-5.128]), distant metastases (0.001, 2.831 [1.520-5.270]), DFS (<0.001, 2.464 [1.571-3.866]), and DSS (0.036, 1.781 [1.040-3.052]) in levels I-III ND patients. An LN density ≥0.048 was an independent predictor of 5-year local control (0.004, 4.871 [1.654-14.344]), neck control (0.002, 24.738 [3.367-181.771]), DFS (<0.001, 4.151 [2.264-7.610]), DSS (<0.001, 3.791 [2.017-7.125]), and OS (<0.001, 2.806 [1.706-4.613]) in levels I-V ND patients. Our findings demonstrate the prognostic value of LN density for guiding treatment strategies in OSCC patients who are to receive adjuvant therapy.

The comparison between weekly and three-weekly cisplatin delivered concurrently with radiotherapy for patients with postoperative high-risk squamous cell carcinoma of the oral cavity

BackgroundThe aim of this study was to compare the outcomes of postoperative adjuvant concomitant chemoradiotherapy using two different schedules of cisplatin for patients with high-risk oral squamous cell carcinoma (OSCC).MethodsFrom Feb. 2008 to Aug. 2010, 55 patients with high-risk OSCC were included in this study. Patients were randomized into treatment groups that either received 100 mg/m2 cisplatin once every 3 weeks (arm A) or 40 mg/m2 cisplatin once per week (arm B). All patients were irradiated with 66 Gy in 33 fractions.ResultsOf the 50 eligible patients, 26 were assigned to arm A, and 24 were assigned to arm B. Both groups of patients received the same mean doses of radiotherapy and cisplatin. However, 88.5% of patients in arm A and 62.5% of those in arm B (p = 0.047) received ≥ 200 mg/m2 of cisplatin in total. The overall toxicity was significantly greater in arm B (p = 0.020), and all of the grade 4 toxicities occurred in patients in arm B.ConclusionsThree-weekly high-dose cisplatin treatment showed higher compliance, and lower acute toxicity compared to weekly low-dose cisplatin treatment.