Infiltration of the thyroid gland by T-cell prolymphocytic leukemia.
BACKGROUND
T-cell prolymphocytic leukemia (T-PLL) is rare, accounting for only 0.06% of all malignant lymphomas, and is classified as a T-cell mature lymphoma. The disease affects mainly elderly patients and is characterized by splenomegaly, lymphadenopathy, skin infiltration, and a high leukocyte count, but thyroid filtration has never been detected as far as we could determine. We report here a case of infiltration of the thyroid gland by T-PLL.


METHODS
An 89-year-old woman who had been treated for Hashimoto's thyroiditis for 20 years presented with a progressively enlarging thyroid mass accompanied by dyspnea and dysphasia. Atypical lymphocytes with irregular nuclei were observed in the peripheral blood. An open biopsy of the thyroid provided pathological evidence of T-PLL, and bone marrow examination showed infiltration by T-PLL. The diagnosis was therefore infiltration of the thyroid gland by T-PLL. Chemotherapy was initiated, but six months after termination, recurrence of neck swelling was observed. The patient was then treated with radiotherapy, but she died of a major stroke 15 months after onset.


CONCLUSIONS
This is the first report of T-PLL infiltration of the thyroid gland, reminding physicians to keep in mind a broad differential diagnosis when encountering a patient with diffuse thyroid lesions and abnormal lymphocytes in the peripheral blood.
1 Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Tottori University , Yonago, Japan .
Kazunori
K
Fujiwara
Takahiro
T
Fukuhara
Hiroya
H
Kitano
Toshiro
T
Okazaki
D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001706:Biopsy; D017338:Cladribine / Q000008:administration & dosage; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000627:therapeutic use; D004317:Doxorubicin / Q000627:therapeutic use; D017809:Fatal Outcome; D005260:Female; D050031:Hashimoto Disease / Q000150:complications / Q000628:therapy*; D006801:Humans; D015461:Leukemia, Prolymphocytic, T-Cell / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D007958:Leukocyte Count; D008206:Lymphatic Diseases; D008942:Mitoxantrone / Q000008:administration & dosage; D009333:Neck / Q000000981:diagnostic imaging; D011241:Prednisone / Q000627:therapeutic use; D012867:Skin / Q000473:pathology; D013163:Splenomegaly; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000556:secondary*; D014057:Tomography, X-Ray Computed; D014750:Vincristine / Q000627:therapeutic use
D017338:Cladribine; D014750:Vincristine; D004317:Doxorubicin; D003520:Cyclophosphamide; D008942:Mitoxantrone; D011241:Prednisone