Recurrent Oral Squamous Cell Carcinoma Research Articles

Effect of salvage surgery for patients with recurrent oral squamous cell carcinoma

To examine the benefit of restaging recurrent oral squamous cell carcinoma (R-OSCC) and the effect on salvage surgery. An analysis was performed on 30 patients with local only first failure (n = 13) or loca-regional only first failure (n = 9) or first recurrence in the neck (n = 8) after surgery and/or radiation treatment given for oral squamous cell carcinoma. All the 30 patients were restaged and treated with salvage surgery. The overall survival time and disease-free survival time of patients with early staged R-OSCC was longer than that of patients with advanced staged R-OSCC. The 1-year survival and 1-year disease-free survival rates for early staged R-OSCC is also higher than that of advanced staged R-OSCC. The re-stage of the recurrent tumor is significantly correlated with survival. The salvage surgery is an effective measure in patients with recurrent oral squamous cell carcinoma, especially in early staged patients of R-OSCC.

Overexpression of Rac-1 small GTPase binding protein in oral squamous cell carcinoma

Purpose Oral squamous cell carcinoma (OSCC) is a fairly common malignancy in Taiwan and most countries of South Asia due to the popularity of areca quid use. In vitro studies have indicated that Rac proteins, a member of ras-related small GTPase protein family, can regulate cytoskeletal structures and activate signaling cascade and have the potential to transform cultured cells. However, Rac alteration during oral carcinogenesis in vivo has yet to be shown. The present study was conducted to investigate the importance of Rac-1 in oral tumorigenesis in vivo. Patients and methods Expression level of Rac-1 protein and mRNA in OSCC together with noncancerous match tissue (NCMT) was explored using immunohistochemistry and reverse transcription—polymerase chain reaction analysis. Results The immunoreactivity of Rac-1 was shown in a significantly higher fraction of OSCC (74%) relative to the 48% in NCMT ( P = .03). Eight of 14 (57%) available tissue pairs also showed overexpression of Rac-1 mRNA in OSCC than that in NCMT. The Rac-1 immunoreactivity did not differ significantly in accord with clinicopathologic parameters including areca quid use. However, 3 of 4 recurrent OSCC studied lacked the Rac-1 immunoreactivity. Conclusions Our results presented novel findings: Rac-1 overexpression is a frequent occurrence in OSCC, highlighting the involvement of GTPase elements in the neoplastic growth of OSCC.

Traumatic Ulceration Mimicking Oral Squamous Cell Carcinoma Recurrence in an Insensate Flap

We report our experience with a patient who developed an ulcer within a free flap 2 months following resection of an oral squamous cell carcinoma. We discuss this clinical problem and the issues it raised, with particular attention to early tumor recurrence and the restoration of sensation in free-flap reconstructions.

Salvage surgery as the primary treatment for recurrent oral squamous cell carcinoma

The choice of salvage modalities of recurrent squamous cell carcinoma (SCC) of the oral cavity remains controversial. We investigated the feasibility of the surgical salvage treatment as a primary option. From 1989 to 1999, curative intended surgery was performed on 191 patients with SCC of the oral cavity at National Cheng Kung University Hospital in Taiwan. These patients were divided into fresh group and salvage group. Survival and complication rates were analyzed for both groups. Patients with early and late recurrent stage had 60 and 38% 5-year absolute survival after salvage surgery. The overall complication rate was higher in the salvage group (60.7 vs 30.4%, P<0.0001), but the major complication rate was not significantly different between these groups ( P=0.121). Surgery achieves an acceptable survival in recurrent oral SCC without increasing the major complication rate. Thus surgery is concluded to be a reliable and feasible treatment of choice.

Nd:YAG laser therapy for palliation of recurrent squamous cell carcinomas in the oral cavity.

The objective of this study was to evaluate the outcome of laser photo-thermoablation for palliation of recurrent squamous cell tumors of the oral cavity. Seventeen patients were treated with the Nd:YAG laser (power output was 50 W) delivered through a curved oral handpiece. Ten patients are alive, 7 with tumor remission, and 3 with persistent disease with an average follow-up of 16 months (range = 2-36). A total of 29 tumor sites received laser treatment with 17 (58%) completely ablated. Stratified by tumor site Nd:YAG treatment led to complete local response in 8/10 buccal mucosa, 2/5 retromolar trigone, 2/2 tongue, 2/5 gingiva, 1/2 floor of mouth, 2/4 hard palate. Nd:YAG laser treatment of recurrent oral cavity squamous cell carcinoma can be performed safely and repeated as needed to achieve tumor palliation. However, extended follow-up may be needed before convincing evidence of long-term therapeutic benefits is obtained.

Expression of 70-kDa heat shock protein in oral lesions: marker of biological stress or pathogenicity.

We showed differential expression of HSP70 during oral tumorigenesis. The precise functional role of HSP70 overexpression in the pathogenesis of betel and tobacco related oral cancer remains to be determined. To evaluate the utility of HSP70 as an indicator of the biological stress experienced by tumour cells or the malignant potential of oral epithelial lesions and predicting clinical outcome, its expression was assessed in different stages of oral carcinogenesis by immunohistochemical analysis and correlated with clinicopathological parameters. Overexpression of HSP70 protein was observed in 38 of 64 (59%) dysplastic lesions and 92 of 125 (74%) oral squamous cell carcinomas (SCCs) which included 76 of 105 cases (72%) of primary oral SCCs and 16 of 20 (80%) of recurrent oral SCCs. A significant correlation of HSP70 expression was observed with severity of dysplasia (P = 0.0006767), poor histological differentiation of primary tumours (P = 0.0184348), increase primary tumour size (P = 0.0221103) and consumption of betel and tobacco (P < 0.01). Follow-up studies showed that in patients with premalignant lesions the median transition time (premalignancy to malignancy) was significantly shorter in HSP70 overexpressing cases than those showing basal level of HSP70 (P = 0.012). Oral cancer patients with elevated levels of HSP70 showed decreased median disease-free survival time (no recurrence/metastasis) than those showing basal HSP70 immunoreactivity (P = 0.0246). The results suggest that HSP70 expression may not be a mere marker of biological stress but may also be implicated in the pathogenesis of oral cancer.

The value of DNA flow cytometry in predicting the development of lymph node metastasis and survival in patients with locally recurrent oral squamous cell carcinoma.

DNA flow cytometry studies of squamous cell carcinoma of the head and neck have shown that patients with diploid tumors have favorable prognoses, whereas the outcomes of those with, aneuploid tumors are poor. This study was conducted to examine the importance of DNA ploidy in patients with locally recurrent oral carcinoma. DNA flow cytometry was performed on 93 primary oral carcinomas and their subsequent recurrences. Eight patients with diploidy of both the primary tumor and the recurrence never developed lymph node metastasis. The 5-year overall survival rate of this group was 87%. For 80 aneuploid primary carcinomas, recurrences developed that were also aneuploid. Only 31% of these patients were 5-year survivors (P < 0.001). Lymph node metastasis at presentation was found in 55% of this group, whereas 13% of initially lymph node negative patients presented with regional disease at second surgery. Five of 13 diploid primary tumors recurred with aneuploid cell lines. Three of these five patients died, two with regional metastasis. The 5-year survival rate of patients with aneuploid recurrences who were never afflicted with lymph node involvement (41%) was better (P < 0.05) than the 5-year survival rate of those with metastasis at presentation or at second surgery (26%). The excellent prognosis of patients with diploid primary tumors can be reestablished by treating local recurrences with radical surgery, if the surgery is performed before aneuploid cell lines have emerged. It appears that aneuploid tumor cell lines acquire unique properties that make them capable of invasion and metastasis.

Glutathione S-transferase π expression in matched human normal and malignant oral mucosa

Over-expression of glutathione S-transferase pi (GST-pi) class isozyme is often associated with malignant transformation and/or drug resistance. To determine whether GST-pi is implicated in betel and tobacco related oral carcinogenesis and/or drug resistance, its expression was studied in oral untreated primary squamous cell carcinomas (SCCs), recurrent tumours and matched normal oral tissues by immunohistochemical and immunoblotting techniques. The GST-pi expression in primary tumours predominantly varied from mild to moderate levels and no significant difference in its expression was observed in the matched normal tissue surrounding these lesions. Mild to moderate levels of GST-pi expression in the oral mucosa of consumers of betel and tobacco observed in the matched normal tissues may support the physiological role of this detoxification enzyme in the metabolism of xenobiotics and elimination of toxic constituents of tobacco. The hallmark of the study is the significant increase in GST-pi expression in recurrent oral SCCs, compared to the matched normal tissues, as well as primary oral tumours, suggesting its potential role as an indicator of prolonged exposure to carcinogens, or prognosis of the disease.