口腔病変の診断混乱をめぐる病理医の鳥瞰図

A bird's-eye view of pathologist over diagnostic confusion of oral cavity lesions.

抄録

はじめに:

口腔内には多くの腫瘍性、前悪性腫瘍性、非腫瘍性の病変が存在する。口腔の病変の診断は、臨床医と病理医にとって常に関心事であり、病変の臨床的外観に依存している。臨床的病変と病理組織学的病変の診断には差がある。口腔癌の多くは、以前に前癌病変を有していた部位に発生する。口腔癌の罹患率は、生活習慣やライフスタイルに関連して若い世代で増加している。これらの病変は、年齢、性別、病変の分布により、臨床症状において誤解を招き、診断のジレンマを引き起こす。口腔粘膜病変の分布を把握することは、口腔病変の診断に役立つ。本研究の目的は、口腔および口腔咽頭の炎症性病変、前悪性病変、良性病変、悪性病変を有する患者における臨床診断と病理組織学的診断の差異を観察すること、および病理組織学的診断による口腔および口腔咽頭病変の臨床的分布を観察することである。

INTRODUCTION: Oral cavity can be host to multitude of neoplastic, premalignant or non neoplastic pathological lesions. Diagnosis of lesions of oral cavity is always of interest to clinician and pathologist and rely on clinical appearance of lesions. There can be variation in diagnosis of clinical lesion with histopathology. Many oral carcinomas arise within the sites that previously had premalignant lesion. Incidence of oral cancers in population has increased among younger generations related to habits and lifestyle. These lesions during clinical presentation are misleading and create diagnostic dilemma owing to age, sex and distribution of lesions. Understanding distribution of oral mucosal lesions helps to diagnose lesions of oral cavity. Purpose of this study is to observe the variation in clinical diagnosis with histopathological diagnosis in patients with inflammatory, premalignant, benign and malignant lesions of oral cavity and oropharynx and also clinical distribution of lesions of oral cavity and oropharynx lesions by histopathology.

観察結果:

全105病変のうち、口腔内潰瘍が58例（55.23％）にみられ、次いで口腔内の腫脹やしこり感が36例（34.29％）、異物感が23例（21.90％）にみられた。口腔内病変の好発部位は舌が33例（31.43％）と最も多く、後臼歯部三角部にみられた症例は2例（1.90％）と少なかった。病理組織学的診断では、前癌病変、非腫瘍性病変、炎症性病変が24例（22.85％）、良性腫瘍が14例（13.33％）、それ以外の67例（63.81％）が悪性であった。Mucocoelは5例（4.76％）、radicular cystは女性患者の1例（0.95％）、Leukoplakiaは4例（1例は軽度異形成）であった。良性腫瘍では、歯肉炎を呈した11例（10.47％）に扁平上皮乳頭腫が5例（4.76％）、線維腫が4例（3.80％）、化膿性肉芽腫が4例（3.80％）、最も多く歯肉にみられ、小唾液腺筋上皮腫が軟口蓋に1例（0.95％）みられた。67例の悪性病変のうち、扁平上皮癌が59例（88.05％）に認められ、次いで疣状癌が3例（4.47％）、基底扁平上皮癌が2例（2.99％）、粘表皮癌が2例（2.99％）、腺様嚢胞癌が1例（1.49％）であった。扁平上皮癌の大部分は高分化型で49例（73.13％）、次いで中分化型が16例（23.88％）、低分化型が2例（2.99％）であった。術後の病理組織検査で扁桃組織の悪性化が認められたのは1例（0.95％）であった。軟口蓋上に筋上皮腫が1例（2.5％）認められた（60歳男性）。

OBSERVATIONS: Out of total 105 lesions, ulcer in oral cavity seen in 58 (55.23%) of patients, followed by swelling or feeling of lump in oral cavity in 36 (34.29%) of patients and foreign body sensation in 23 (21.90%) of patients with tongue as most frequent site for most of lesions of oral cavity accounting in 33 (31.43%) of cases, and less frequently lesions were seen in retro molar trigone area in 2 (1.90%) patients. Histopathological diagnosis of premalignant, non neoplastic and inflammatory lesions was made in 24 (22.85%) cases, benign tumours were diagnosed in 14 (13.33%) cases and rest of 67 (63.81%) lesions were malignant. Mucocoel were seen in five (4.76%) cases, radicular cyst was seen in one (0.95%) case of female patient and four cases of Leukoplakia with one case showing mild dysplasia. Among benign tumours 11 (10.47%) patients presented with gingivitis turned out to be squamous papillomas were seen in five (4.76%) cases, fibroma was diagnosed in four (3.80%) cases, pyogenic granuloma was diagnosed in four (3.80%) cases most commonly seen over gingiva and myoepithelioma of minor salivary gland was observed in one (0.95%) case over soft palate. Out of 67 cases of malignant lesions squamous cell carcinomas were seen in 59 (88.05%) cases followed by verrucous carcinoma in 3 (4.47%) cases, 2 (2.99%) cases were basaloid squamous cell carcinomas, mucoepidermoid carcinoma was seen in 2 (2.99%) cases and 1 (1.49%) case of adenoid cystic carcinoma was seen. Majority of squamous cell carcinomas cases in study were well differentiated in 49 (73.13%) cases followed by moderately differentiated in 16 (23.88%) cases and poorly differentiated in 2 (2.99%) cases. Malignant transformation of tonsil tissue post operatively was observed in 1 (0.95%) patients on histopathology. One (2.5%) case of myoepithelioma was seen in 60 years male over soft palate.

結論:

本研究で報告されたすべての口腔生検のうち、低年齢層における悪性腫瘍の増加傾向は、地域社会に対する新たな脅威であり、この疾患の危険因子および結果に関する一般市民の認識を高めるための効果的な対策を講じる必要性を強調している。これを克服するために、25歳以上を対象としたスクリーニングプログラムが推奨される。

CONCLUSION: Of all oral biopsies reported in study, increasing trend of malignancies in lower age groups of population making it an emerging threat to community and highlighting need to take effective measures to increase public awareness about risk factors and consequences of this condition. Screening programmes targeted to population over 25 years are recommended to overcome this.