title: Primary thyroid diffuse large B-cell lymphoma coexistent with papillary thyroid carcinoma: A case report.
abstract: BACKGROUND
  Primary thyroid lymphoma (PTL) is uncommon, accounting for 2% to 5% of all thyroid malignancies. Papillary thyroid carcinoma (PTC) is the most frequent thyroid cancer. The coexistence of PTL and PTC is very rare, and the preoperative diagnosis is rather difficult.
  
  
  METHODS
  A 41-year-old male patient complaining of fast painless thyroid enlargement for 2 months and a cervical mass for half a month was presented. Imaging demonstrated an enlarged thyroid and a mass in the thyroid.
  
  
  RESULTS
  Surgery was conducted, and the final diagnosis of coexistence of PTL and PTC was confirmed by histopathological and immunohistochemical examination. The patient was then treated with cyclophosphamide, hydroxy doxorubicin, oncovin, prednisone (CHOP) chemotherapy and radiotherapy. After 2 months of follow-up, no recurrence or metastasis was noted.
  
  
  CONCLUSIONS
  This rare case highlights the importance for physicians to keep PTL in mind for differential diagnosis in patients with sudden thyroid enlargement and who have clinical history of Hashimoto thyroiditis.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.
authors.forename: Shumin
authors.initials: S
authors.lastname: Xie
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Human Anatomy, University of South China, Hengyang, People's Republic of China.
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Xiang
authors.affiliation: Department of Pathology, The Second Xiangya Hospital of Central South University, People's Republic of China.
authors.forename: Yinghuan
authors.initials: Y
authors.lastname: Dai
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.
authors.forename: Jihao
authors.initials: J
authors.lastname: Ren
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D002277:Carcinoma / Q000473:pathology* / Q000628:therapy; D002291:Carcinoma, Papillary; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology* / Q000628:therapy; D008297:Male; D009378:Neoplasms, Multiple Primary / Q000473:pathology* / Q000628:therapy; D035583:Rare Diseases; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000628:therapy; D013965:Thyroidectomy / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler
keywords: coexistence; diffuse large B-cell lymphoma; papillary thyroid carcinoma; primary thyroid lymphoma; therapy