Richard Che-Shoa Chang

Outcomes of oral squamous cell carcinoma in Taiwan after surgical therapy: factors affecting survival.

PURPOSE The study goal was to determine which clinical features correlated with 5-year survival in patients surgically treated for oral squamous cell carcinoma (OSCC) in Taiwan. PATIENTS AND METHODS The records of 378 OSCC patients surgically treated with or without chemotherapy and radiotherapy were reviewed retrospectively. Their 5-year survival in relation to age, gender, tumor site, lymph node involvement, presence of distant metastasis, staging, differentiation, and risk factors, including betel quid (BQ) chewing, cigarette smoking, and alcohol consumption, was analyzed. RESULTS The majority of the patients were men (male-to-female ratio, 5.87:1) with the mean age of 57.1 +/-11.7 years. Tumors occurred mainly at the buccal mucosa (BM) (100 of 378, 26.5%), gingiva (105 of 378, 27.8%), and tongue (103 of 378, 27.2%). Neck nodal metastasis occurred frequently at the floor of the mouth (in >60% of cases), followed by the gingiva (45.7%), buccal mucosa (34%), and tongue (20.4%), whereas early distant metastasis was rare (5.3%). There were 104 (27.5%) stage 1, 96 (25.4%) stage 2, 98 (25.9%) stage 3, and 80 (21.2%) stage 4 patients. OSCC at the BM and gingiva was most (and at the tongue least) associated with risk factors of BQ use and smoking. The 5-year survival was 75%, 65.6%, 49%, and 30% for patients with stage I, II, III, and IV, respectively. The size, nodal involvement, distant metastasis, staging, differentiation, and BQ use significantly affected the survival (P <.05, Kaplan-Meier analysis). BQ use also correlated most significantly with the younger age of occurrence of OSCC patients. CONCLUSIONS Our data suggest that early treatment is the key to increasing the survival of OSCC patients. Periodic screening of high-risk populations for OSCC represents an urgent need in Taiwan.

Characterization of two new cell lines derived from oral cavity human squamous cell carcinomas--OC1 and OC2.

Two continuous cell lines, OC1 and OC2, have been established. Each one was derived from a surgical specimen of buccal mucosa squamous carcinoma from a Chinese man. Both cell lines grew as adherent monolayers and had an epithelioid morphology. The cell lines have now been grown in vitro for more than 200 passages over a 2-year period. Both cell lines were tumorigenic in nude mice. Histologic examination of the mice tumors showed a positive identification with those from the original human squamous cell carcinoma. Electron microscopic examination convincingly demonstrated their epithelial origin. Chromosomal numbers of the OC1 cell ranged from 58 to 78 and of the OC2 cells ranged from 62 to 82. Analysis of cytokeratin showed that all cell lines were positive. The carcinoembryonic antigen (CEA) tested negative in these two cell lines. The OC2 cell line showed the presence of HPV16, but the OC1 cell line did not. These cell lines should be useful for investigation of anticancer treatment and for their possible relationship to human papilloma virus (HPV).

Transpositioned flap vestibuloplasty combined with implant surgery in the severely resorbed atrophic edentulous ridge.

The use of transpositioned flap (lipswitch) vestibuloplasty combined with implant surgery in patients with severely resorbed atrophic edentulous ridges is reviewed. The cases of 17 patients with severely resorbed atrophic edentulous ridges at the mandible undergoing implant rehabilitation were reviewed. Lipswitch vestibuloplasty was followed immediately by the implant surgery. Postoperative follow-up consisted of clinical and radiographic examinations. Seventeen patients with atrophic ridges (12 class II and 5 class III) each had 2 implant fixtures placed in the mandible as abutments for a clip and bar overdenture. The average time of follow-up was 6 years. Before surgery, all patients had severely atrophic ridges with a compromised shallow vestibule of varying degrees. Satisfactory results were observed in regard to the immediate and long-term morphology of the vestibule, the health of the peri-implant tissue, the stability of implant fixtures, and the functionality of the prostheses. The lipswitch vestibuloplasty offers a safe and convenient method of surgical access for implant fixture installation, with the advantage of rebuilding the vestibule of a compromised atrophic ridge in the anterior mandible.

Sebaceous carcinoma of buccal mucosa: Report of a case

A case of sebaceous carcinoma arising in the buccal mucosa is described.

Reconstruction of the severely resorbed atrophic edentulous ridge of the maxilla and mandible for implant rehabilitation: report of a case.

We describe a case with a severely resorbed atrophic edentulous ridge in both the maxilla and mandible. The maxilla was reconstructed using a sinus-lifting procedure and onlay bone graft. The mandible was reconstructed by anterior osteotomy with an interpositional sandwich iliac bone graft at the symphysis area, subperiosteally with iliac bone chips mixed with hydroxylapatite bilaterally at the posterior atrophic ridge, and vestibuloplasty with a split thickness skin graft (STSG). After full-mouth implant rehabilitation, a 5-year follow-up of this case shows a satisfactory result.

Maxillary odontogenic carcinoma with distant metastasis to axillary skin, brain, and lung: Case report

We present a case of odontogenic carcinoma with ghost-cell keratinization of the right maxilla, with a history of 23 years after initial treatment. Within this period, multiple local recurrence, as well as metastasis to axilla, brain, and lung, was noted. Several attempts at resection of the primary lesion were unsuccessful at achieving local control, even when supplemented with chemotherapy and radiotherapy. Metastatic tumors were studied histologically, and their morphology coincided with that of the primary tumor. The medical history of the patient and pathologic findings of the tumor are reviewed.

Biomechanical and histological studies of particulate hydroxylapatite implanted in femur bone defects of adult dogs.

The purpose of this study was to investigate the biomechanical behavior and the histology of particulate hydroxylapatite (HA) implanted in bone defects created in femurs of 48 adult mongrel dogs. The bone defects, measuring 10 x 10 x 25 mm with or without HA implantation, were allowed to heal until the end of the 1st, 2nd, 3rd, 6th, 9th and 12th months after surgery. The harvested tissue specimens from the implant sites were processed into long cubic or rectangular prismatic forms. Their mechanical strengths were assessed using compression and shearing tests to measure the maximal compressive and shear stress by force loading on the middle portions of the specimens. Histological sections of each stage were processed with both decalcified and nondecalcified methods. The results showed that the mechanical strength of the tested specimens was closely related to the tissue regeneration within the bone defect. Progressive regeneration of new bone was observed at each stage, with complete bone formation at the 9-month period. A consistent increase in both maximal compressive stress and maximal shear stress was noted at each stage, responsive to the ossification and maturation of the regenerating tissue within the bone defect. This animal model provides a novel approach to directly estimate the tissue strength of the HA-implanted bone defect.

Hemangiopericytoma of the parotid gland: Report of case

Abstract Hemangiopericytoma is a rare vascular tumor arising from the proliferation of pericytes that surround capillaries. This tumor can occur in almost every region of the body, but most often occurs in the soft tissues of the extremities.1–3 The term hemangiopericytoma was first coined by Stout and Murray4 in 1942. It represents 1% of all vasoformative neoplasms, 15% to 25% of which occur in the head and neck region.5 Review of the literature by Pagliaro et al6 in 1988 revealed 18 cases located in the parotid gland. No additional cases have been reported since that time. This article presents a primary hemangiopericytoma in the parotid gland of a Chinese boy.

Aspergillosis of the temporomandibular joint following irradiation of the parotid region: A case report

We report a case of aspergillosis in the right temporomandibular joint (TMJ) with a history of parotid carcinoma and post-irradiation otitis. Previous treatment attempts with surgery and antibiotics were unsuccessful. Radical debridement of the glenoid fossae, supplemented with amphotericin B and adjunct hyperbaric oxygen (HBO) therapy, was provided to resolve the symptoms. This case report highlights the need to be aware of the possibility of invasive mycosis in immunocompromised patients.

Implant Rehabilitation of Severely Traumatized Maxillary Anterior Alveolar Ridge with Mandibular Ramus Autogenous Bone Graft-Cases Analysis

The use of manduibular ramus autogenous bone graft followed by implant surgery in 6 patients who had suffered from maxillofacial injury is reviewed. Six patients had severely deficient alveolar ridge and loss of teeth due to maxillofacial injury from motorbicycle accident. All cases underwent stepwise reconstructive procedures at the edentulous area with (1) autogenous bone graft from mandibular ramus, (2) implant surgery (3) soft tissue management (4) prosthesis rehabilitation. Postoperative follow-up consisted of clinical and radiographic examinations. Six patients with compromised ridges had 16 implant fixtures placed in the maxilla. The average time of follow-up was 4 years. Before surgery, all patients had severely deficient ridges with a compromised shallow vestibule of varying degrees. Satisfactory results were observed in regard to the immediate and long-term stability of the morphology of reconstructed ridge height and width, morphology of vestibule, the health of the pen-implant tissue, the stability of implant fixtures, and the functionality of the prostheses. The proposed reconstructive procedure offers a stable method of implant rehabilitation in cases with traumatic injury.