Hiroshi Iwaki

Oral malignant melanoma in Japan.

Clinical examination was performed on 20 cases of malignant melanoma in the oral region encountered at the First Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Tokyo Medical and Dental University, during the 22-year period from 1970 to 1991. In addition, we reviewed 140 cases reported in the Japanese literature since the last major review in 1974. The results of our study revealed that the clinical course of malignant melanoma in the oral region is worse than oral squamous cell carcinoma and that treatment by radiotherapy is effective in prolonging the life of these patients. Clinically, the tumors were classified into five types: (1) pigmented nodular type; (2) nonpigmented nodular type; (3) pigmented macular type; (4) pigmented mixed type; and (5) nonpigmented mixed type. We suggest that oral malignant melanoma might be different from cutaneous malignant melanoma and that new criteria for diagnosis and therapy for oral disease should be considered.

Pigmented villonodular synovitis of the temporomandibular joint: differential diagnosis and case report

Pigmented villonodular synovitis of the temporomandibular joint (TMJ) is rare. We present a patient in whom the lesion had invaded the infratemporal fossa and destroyed the mandibular condyle.

Oral pseudotumor: benign polypoid masses following radiation therapy.

The current study evaluated postirradiation pseudotumor in the oral cavity to investigate clinical and pathologic characteristics and incidence rates.

Clinicopathological study of carcinomas of the lip and the mucosa of the upper and lower lips

AbstractBackground. Lip carcinomas are rare oral tumors, and there have been few reports of lip carcinoma in Japan. Methods. Of 914 patients with oral carcinomas treated between January 1980 and December 1998, 12 (1.3%) had lip carcinoma and 5 (0.5%) had lip mucosal carcinoma. We investigated the clinicopathological features of these 17 patients. Results. Of the 12 patients with carcinoma of the lip, 10 had squamous cell carcinomas (9, external lower lip; 1 commissures) and 2 had mucoepidermoid carcinomas (external upper lip). Of the 5 patients with lip mucosal carcinoma, 3 had squamous cell carcinomas (2, mucosa of the lower lip; 1, mucosa of the upper lip), 1 had mucoepidermoid carcinoma (mucosa of the lower lip), and 1 had acinic cell carcinoma (mucosa of the lower lip). Of the 12 patients with lip carcinoma, 9 were classified as stage I, 2 as stage II, and 1 as stage III; all 5 of the patients with lip mucosal carcinoma were stage I. Five patients with lip carcinoma were treated by resection, 5 by a combination of resection and reconstruction, and 2 by radiotherapy alone. All patients with lip mucosal carcinoma were treated by resection. After the initial therapy, 3 patients without neck dissection had regional recurrences and received delayed neck dissection, and 2 died with neck regional recurrence after dissection. The 5-year cumulative survival rates of the patients with lip carcinoma and those with lip mucosal carcinoma were 82.5% and 80.0%, respectively. Conclusion. We suggest that early-stage carcinomas of the lip and of the mucosa of the upper and lower lips are frequent, and we found that the outcome of these patients was excellent. However, an aggressive therapeutic approach to the lip carcinoma patient with cervical metastasis appears warranted, in an attempt to improve locoregional control and ultimate survival.

Homozygous deletions on the short arm of chromosome 3 in human oral squamous cell carcinomas

Recent cytogenetic and allelic deletion analyses have demonstrated that deletions on the short arm of chromosome 3 (3p) are frequently found in various cancers, including oral squamous cell carcinomas (OSCCs). This suggests that one or more tumor suppressor gene(s) for these malignancies might be located on 3p. In the present study, to further define the region(s) on 3p that harbor putative tumor suppressor gene(s) for OSCCs, we have investigated the existence of homozygous deletions (HDs) at 34 loci on 3p, in 14 OSCC cell lines. HDs were detected within the FRA3B region at 3p14.2 in only two cell lines (HSC-4 and TSU). Recently, the human fragile histidine triad (FHIT) gene was isolated from this region, abnormalities of which have been found at high frequencies in several types of human cancers. We also examined the expression of the FHIT gene, using reverse transcription-polymerase chain reaction (RT-PCR) and exon-specific PCR, in the two OSCC cell lines which showed HDs at 3p14.2. There was no detectable expression of exon 5, which was the first protein-coding exon of FHIT gene, in HSC-4 cells, indicating that this region was homozygously deleted in this cell line. On the other hand, HD in the TSU cells did not affect the coding region of the FHIT gene, and the wild-type transcript was detected by RT-PCR. Therefore, several candidate tumor suppressor genes, including the FHIT gene, may reside in these homozygously deleted regions. To our knowledge, this is the first report of HDs on 3p in OSCCs.

Analysis of Bilateral Neck Metastasis of Tongue Cancer

Abstract To estimate the prognosis of bilateral cervical metastases from tongue carcinoma, we studied twelve patients (24–72 years old) who underwent neck dissections at our hospital to judge whether we should have performed radical treatment or not for those patients of tongue carcinoma who had bilateral metastatic nodes. The five-year survival rate of bilateral neck metastasis patients was 58% (the Kaplan-Meier method). On the other hand, the five-year survival rate of patients with only unilateral neck metastases of squamous cell carcinoma of the tongue was 56%. Thus, there was no statistical significant difference in survival rate. We conclude that even if a patient has metastatic lymph nodes on both sides of the neck, radical therapy should be done.

Preoperative computed tomography for determining nodal status combined with histologic grading as a prognostic factor for patients with tongue carcinoma

ObjectivesTo evaluate the predictive value of preoperative neck computed tomography (CT) in combination with histologic grading as a prognostic factor for patients with tongue carcinoma.MethodsFifty-five patients with squamous cell carcinoma of the tongue were examined by CT prior to radical neck dissection. The locoregional failure and survival rates of these patients were analyzed in relation to their clinical characteristics, histologic grading (World Health Organization, WHO) based on tongue biopsy, and imaging diagnoses prior to surgery.ResultsLogistic multivariate regression analysis showed that both histologic grading and number of metastic lymph nodes on CT were significant and independent prognostic factors in locoregional failure (p=0.009 and p=0.009, respectively). When the number of metastatic lymph nodes detected on preoperative neck CT were combined with the histologic grading for the evaluation, the five-year overall survival rates of A group (0 node with any Grade, or 1 node with GradeI–II) and B group (1 node with GradeIII, or 2 or more nodes with any Grade) were 74.5% and 37.5%, respectively (p=0.001). The difference was more significant than histologic grading alone or the number of metastatic lymph nodes seen on CT alone.ConclusionsThe combination of preoperative neck CT with histologic grading of the primary tumor is useful as a prognostic indicator for patients with tongue carcinoma.To evaluate the predictive value of preoperative neck computed tomography (CT) in combination with histologic grading as a prognostic factor for patients with tongue carcinoma. Fifty-five patients with squamous cell carcinoma of the tongue were examined by CT prior to radical neck dissection. The locoregional failure and survival rates of these patients were analyzed in relation to their clinical characteristics, histologic grading (World Health Organization, WHO) based on tongue biopsy, and imaging diagnoses prior to surgery. Logistic multivariate regression analysis showed that both histologic grading and number of metastic lymph nodes on CT were significant and independent prognostic factors in locoregional failure (p=0.009 and p=0.009, respectively). When the number of metastatic lymph nodes detected on preoperative neck CT were combined with the histologic grading for the evaluation, the five-year overall survival rates of A group (0 node with any Grade, or 1 node with GradeI–II) and B group (1 node with GradeIII, or 2 or more nodes with any Grade) were 74.5% and 37.5%, respectively (p=0.001). The difference was more significant than histologic grading alone or the number of metastatic lymph nodes seen on CT alone. The combination of preoperative neck CT with histologic grading of the primary tumor is useful as a prognostic indicator for patients with tongue carcinoma.

Ultrasonic study of schwannoma of the oral and maxillofacial region: Comparison of ultrasonograms and pathologic findings

Ultrasonographic study of a schwannoma of the oral and maxillofacial region have rarely been reported. Here we report ultrasonographic findings from the nine cases of schwannoma located in that region that we encountered between 1984 and 1995. The tumor was delineated as a hypoechoic mass with a sharply demarcated contour and posterior echo enhancement. Change in the internal echo followed pathologic degenerative changes: cystic change, bleeding, myxomatous change, and hyaline degeneration. The internal echo was in agreement with the description of Antoni type A tissue, showing hemorrhagic and hyaline degeneration in the tumor. The cystic pattern of the ultrasonogram corresponded to cystic change, and hypoechoic area of the ultrasonogram corresponded to Antoni type B tissue and myxomatous change. The internal echo pattern on the ultrasonogram of a schwannoma was found to reflect the pathologic structure of the tumor.

Postoperative speech function in patients of cancer of floor of mouth with immediate surgical reconstruction. An oncology group study.

根治手術後に即時再建手術を行った口底癌19症例の術後の構音機能と手術との関連性を分析した。評価方法は日本語100語音による発語明瞭度検査である。対象症例の内訳を軟組織の再建方法別にみると, 遊離前腕皮弁移植症例が12例, 大胸筋皮弁移植症例と腹直筋皮弁移植症例がそれぞれ3例, 前腕皮弁と大胸筋皮弁の併用症例が1例であった。舌の切除範囲別では, 舌部分切除症例が14例, 可動部半側切除症例が1例, 半側切除症例が1例, 亜全摘出症例が3例であった。これらの症例について原発腫瘍の大きさ, 切除範囲, 切除様式, 軟組織の再建方法, 下顎骨の再建方法と術後の構音機能の関連について検討した。その結果, 原発腫瘍の大きさによる術後の構音機能の差は少なかったが, 舌の切除範囲が大きくなると構音機能は低下していた。切除様式については側方型の切除を受けた症例の明瞭度は前方型の切除を受けた症例よりも明らかに高く, 切除様式による発音機能の差異が明らかであった。前方型の切除を行った症例の術後の発音障害を防ぐためには, 手術法の改善が必要であり補綴物の応用が有用であることが示唆された。