Exfoliative cytology of a case of bronchial granular cell myoblastoma.

cell myoblastoma have been reported since the first case was described by Abrikossoff' in 1926, but only seven, including the present case, were found in the bronchial tree. The histogenesis of this tumor is obscure; many theories have been proposed. Abrikos-soff' thought its origin to be embryonic muscle cells, and Murray8 came to the same conclusion through tissue culture studies while Gullino' regarded this tumor as a granuloma induced by parasites. Roffo'#{176} believed that there was no real tumor involved , but only granular myolysis. Fust and Custer' narrowed their choice of origin to either fibroblasts (endoneurium), or the Schwann cells of the peripheral nerves. Histiocytes, altered fibroblasts, and degen-erative or regenerative changes in striated muscle have also been suggested. REVIEW OF THE LITERATURE In 1939, Kramer' reported the first case of bronchial granular cell myoblastoma, which was resected locally. The present case, from the University Hospital, was reported by Ramsey9 in 1955. The bronchial washing which was taken at the time was recently reviewed and typical myoblastic cells were found which have never been previously described in cytologic smears. Peterson et al.8 reported two other cases of bronchial granular cell myoblastoma in 1957; one was excised locally and the other was treated by segmental resection. Herbert et al.4 published another case in 1957 that was treated by lobectomy; then Nora et al.' in 1961 reported two additional cases treated by bronchoscopic local excision followed in one by radon seed implantation. FIGURE 1 (upper): Exfoliated giant myoblastic cell in a bronchial washing smear (Papanicolaou stain X 415). Part of the myoblastic cell showing the granular cytoplasm and the small vesicular nucleus (Papanicolaou stain X 830). FIGURE 3 (lower): Bronchial tumor showing the granular myoblastic cells (Hematoxy-lin and Eosin stain, X245).