Granulocyte-colony stimulating factor-producing malignant phyllodes tumor of the breast: a rare case

Abstract

Background Granulocyte-colony stimulating factor (G-CSF)-producing tumors can cause leukocytosis despite an absence of infection. G-CSF-producing tumors have been reported in various organs such as the lung, esophagus, and stomach but rarely in the breast. We report a case of G-CSF-producing malignant phyllodes tumor of the breast. Case presentation An 84-year-old woman visited our hospital complaining of a lump in her left breast without fever and pain. Laboratory tests revealed elevated white blood cell (WBC) count and G-CSF levels. A malignant tumor of the breast was diagnosed by core needle biopsy. We performed a total mastectomy and sentinel lymph node biopsy. The tumor was identified as a G-CSF-producing malignant phyllodes tumor. Within 7 days after surgery, the patient’s WBC count and G-CSF level had decreased to normal levels. She is alive without recurrence 13 months after surgery. Conclusions We encountered a rare case of G-CSF-producing malignant phyllodes tumor of the breast. PET–CT revealed diffuse accumulation of FDG in the bone. Phyllodes tumors need to be differentiated from bone metastasis, lymphoma, and leukemia. We must be careful to not mistake this type of tumor for bone marrow metastasis.

18F-FDG PET/CT Imaging of G-CSF–Producing Dedifferentiated Liposarcoma

“…4 There have been several reports regarding the 18 F-FDG PET or PET/CT appearance of G-CSF-producing tumors. [5][6][7][8][9][10][11][12] Morooka et al 12 presented the 18 F-FDG PET/CT findings of 2 cases with G-CSF-producing lung cancer that showed abnormally high uptake of 18 F-FDG not only by the tumor itself but also diffusely throughout the bone marrow. The authors commented that diffuse accumulation of 18 F-FDG throughout the bone marrow with a markedly elevated uptake of 18 F-FDG in the primary tumor may be helpful in the diagnosis of G-CSF-producing tumor, especially in a patient with abnormally high WBC counts.…”

“…Although the physiological uptake of 18 F-FDG in the bone marrow has been reported previsouly, 1 diffuse bone marrow 18 F-FDG uptake is often indicative of diffuse bone marrow metastasis, 2 hematological disorders with hyperplastic bone marrow, 3 or administration of bone marrow–stimulating agents including G-CSF 4 . There have been several reports regarding the 18 F-FDG PET or PET/CT appearance of G-CSF–producing tumors 5–12 . Morooka et al 12 presented the 18 F-FDG PET/CT findings of 2 cases with G-CSF–producing lung cancer that showed abnormally high uptake of 18 F-FDG not only by the tumor itself but also diffusely throughout the bone marrow.…”