宮本 勲

症例は78歳女性で、下顎歯肉に無痛性の腫瘤と潰瘍を認め、近在歯科医院を受診した。口内炎と診断されステロイド軟膏にて経過を診ていたが、症状が改善しないため精査加療目的に当科を紹介され受診した。初診時に下顎歯肉腫瘤より擦過細胞診を行い、リンパ増殖性疾患が強く疑われた。病理組織学的にび漫性大細胞型B細胞性リンパ腫と診断されたため、全身検索と治療を当院血液内科に依頼した。PET-CTにおいて右側顎下リンパ節に軽度の集積を認めたが、血液内科では反応性のものと考え、腫瘤が下顎歯肉の限局性病変であったこと、発熱、発汗、体重減少がなかったことから、Ann Arborの臨床病気分類はStage IEA期と診断した。血液内科にて抗CD20モノクロナール抗体を併用したCHOP療法を6コース施行し、経過中に髄腔内抗腫瘍薬を2回投与した。化学療法終了後、下顎歯肉の腫瘤は消失し、1年10ヵ月経過した現在、再発なく経過は良好である。

Calcium pyrophosphate dihydrate crystal deposition disease (CPPDd) induces arthritis in the surrounding joints with symptoms, such as pain, swelling, and restricted joint movement. CPPDd occurs primarily in the major joints; however, the main manifestation of this disease in the temporomandibular joint (TMJ) is relatively rare. We describe a case of CPPDd in the TMJ of a 54-year-old Japanese woman who was referred to our hospital with the complaints of unpainful swelling in the right TMJ region and restricted mouth opening. Computed tomography (CT) and magnetic resonance imaging (MRI) showed 46 x 42-mm and 27 x 18-mm calcified masses in the right TMJ region. The masses were both outside and inside the mandibular condyle, both of which extended to the skull base. Since we suspected a tumor in the TMJ, the lesion was partially excised for biopsy with the patient under general anesthesia. The microscopic examination showed deposits of calcium pyrophosphate dihydrate crystals, which resulted in a histopathologic diagnosis of CPPDd. According to the suggestion of the neurosurgeon, we removed as much as possible of only the CPPDd tissue on the outside of the mandibular condyle via the preauricular approach to avoid damaging the cranial nerves. The patient was satisfied with the postoperative facial symmetry without limited mouth opening. The postoperative follow-up was uneventful.

Cemento-osseous dysplasia (COD) of the jaw is a benign fibro-osseous lesion that is subdivided into three types, periapical, focal, and florid, based on the clinical and radiologic features. Focal COD (FCOD) usually affects the posterior tooth-bearing area or edentulous alveolar process and typically presents as an asymptomatic lesion diagnosed incidentally on dental radiography. In asymptomatic cases, once the diagnosis has been established, invasive treatment is not required. However, routine follow-up is warranted, because some patients develop multiple-site involvement, i.e., florid COD. Symptomatic patients require treatment. We describe the unusual case of a 19-year-old Japanese woman with FCOD in the left maxillary sinus who presented with repeated discomfort in the left side of the cheek. Radiographic examinations showed a mixed radiolucent-radiopaque, well-defined maxillary mass that obliterated nearly the entire left maxillary sinus. We planned to remove the lesion to restore the nasal ostium patency and natural sinus clearance mechanism, because clinical symptoms were considered to result from obliteration of the maxillary sinus by the lesion. The lesion was enucleated via the intraoral approach under general anesthesia. The microscopic examination showed a dense hypocellular sclerotic mass composed of compact bone-like cemento-osseous tissue with irregular lamellar structures. The final diagnosis was determined to be FCOD considering the combination of clinical, radiologic, and histopathological findings. The clinical outcome was satisfactory without postoperative infection or complications.