Yuuichi Sasakura

Myasthenia gravis associated with reduced masticatory function

This paper describes a case of myasthenia gravis in a 38-year-old woman who first consulted a dentist and then an oral surgeon because of chewing difficulty. Although myasthenia gravis commonly presents with diplopia, ptosis, or both as initial symptoms, chewing difficulty is rare. The patient was given steroid therapy and underwent thymectomy. Changes in bite force were monitored during treatment. The bite force was low when a high titer of anti-acetylcholine receptor antibody (11.0 nmol/l, normal <0.2) was found in the blood, but increased after the titer had decreased (1.5 nmol/l) in response to therapy.

Complete Recovery from Complications of Microvascular Free-flap Transfers after Oral Tumour Extirpation

Abstract Objective: In this retrospective study, all free-flap transfers done at the Kanagawa Dental College, Kanagawa, Japan, for reconstruction following ablation of head and neck tumours were analysed. The 5 patients who developed complications following reconstructive surgery and the course of recovery were examined. Patients and Methods: Thirty four microvascular free-flap transfer operations were performed, which included patients with cutaneous radial forearm (17; 50%), myocutaneous rectus abdominis (13; 38%), osteocutaneous scapula composite (2; 6%), osteocutaneous scapula composite with forearm chimera (1; 3%), and myocutaneous rectus abdominis with forearm chimera (1; 3%). Results: Complications were seen in the forearm (n = 2), osteocutaneous scapula composite (n = 2), and chimeric (scapula composite + forearm) [n = 1] microvascular free flaps. The facial artery showed the most complications when used as a recipient artery, presenting 2 complications in 4 inosculation cases; only 2 complications (7%) were observed for the superior thyroid artery (n = 28). The most frequently used recipient vein, the internal jugular vein (n = 27), showed 3 complications (11%). The presenting complications were first observed at 0.5, 4, 36, and 58 hours (mean ± standard deviation, 19.8 ± 26.1 hours) in the 5 patients with complication. Thrombosis was related to the cause of all complications, including bending of the anastomosis (n = 1), distorted pedicle (n = 1), oppression of the pedicle (n = 1), oppression due to coagulation in the surrounding scar (n = 1), and unknown factors (n = 1). Complete recovery was achieved in all patients. Conclusion: Early detection of complications, with diligent and meticulous postsurgical follow-up, is key to achieving complete recovery rates following free-flap transfer surgeries.

Specific Identification of Telomerase Activity and p53 Gene Product in Metachronous Multiple Oral Squamous Cell Carcinoma and Adjacent Tissues

Abstract Objectives: To define the association of telomerase activity, histopathological characteristics, and p53 gene product expression in metachronous oral squamous cell carcinomas. Patients and Methods: Three regions of tissue specimens from the tumour, the region adjacent to the tumour, and intact oral mucosa from the surgical margin from 2 patients were simultaneously evaluated. Telomerase activity was determined by telomeric repeat amplification protocol assay. Hematoxylin and eosin stain and DO7 monoclonal antibody were used to stain formalin-fixed, paraffin-embedded sections to examine the histopathological features and p53 gene product expression. Results: Marked telomerase activity was expressed in tumour tissue and in adjacent dyskeratotic tissue. No telomerase activity was found in hyperkeratotic or dysplastic oral mucosa. Although p53 gene product was detected in the tumour and adjacent regions of both patients, it was found in the intact oral mucosa of only 1 patient. Conclusion: Estimation of tissue telomerase activity and p53 gene product expression is helpful in identifying malignancy in oral mucosal lesions.

The change of the immunological functions of cancer patients with the administration of interleukin-2

進行性口腔癌3症例に対しinterleukin-2 (IL-2) を投与して, 免疫学的活性を観察した。症例1: 77歳の男性, 頬粘膜再発性扁平上皮癌。2.59×107JRU (Japan Reference Unit) のIL-2を腫瘍周囲の組織内に24日間注射した。腫瘍の縮小が認められ, PRと診断したが, その後腫瘍は増殖し, 患者は4年後に死亡した。症例2: 66歳の女性, 頬粘膜の進行性扁平上皮癌。7.7×106JRUのIL-2を11日間静注した。腫瘍は増殖し, 放射線や化学療法を行ったが2か月後に死亡した。症例3: 63歳の男性, 上顎洞扁平上皮癌。上顎切除後, 翼突窩に腫瘍の残存が認められた。1.54×107JRUのIL-2静注が60Co照射と併用された。患者は1988年以来, 腫瘍を認めず生存中である。好酸球は症例1で増加し, リンパ球は症例1および3で増加した。数種類のリンパ球phenotypeは症例2で高値を示したが, 処置後は増加しなかった。症例1および3においてはCD57とCD16がIL-2投与後増加した。NKおよびLAK活性もまた投与後増大した。