Diagnostic utility of bone marrow examination for the assessment of patients with fever of unknown origin: a 10-year single-centre experience.

Bone marrow (BM) examination is included in the diagnostic algorithm of fever of unknown origin (FUO), although its role is not clearly determined. The purpose of this study was to assess the role of BM studies in patients with FUO. We retrospectively reviewed 45 consecutive patients (25% human immunodeficiency virus-positive) with FUO who underwent a BM study in the University Hospital of Salamanca from 2000 to 2010. We analysed the diagnostic role of BM smears, multiparameter flow cytometry analysis, histology and microbiological cultures. Five patients (11%) were finally diagnosed by BM study (three had an infectious disease and two were found to have haematological malignancies), all of whom were immunocompetent patients. Histology was the most useful study (diagnosis was obtained in 4/5 patients), while BM cultures did not establish the final diagnosis in any patient. Flow cytometry established the diagnosis in one patient, although this patient was also diagnosed by histology. In conclusion, BM study is useful for establishing the aetiology of FUO. BM biopsy for histological examination should be always mandatory if a BM examination is performed.

Increased incidence of second neoplasms in patients treated with interferon alpha 2b for hairy cell leukemia: a clinicopathologic assessment.

We report that there is an unexpectedly high incidence of second neoplasms in patients after treatment of hairy cell leukemia (HCL) with interferon alpha 2b (IFN). In a cohort of 69 patients with HCL entered in a protocol using IFN as the primary treatment, and followed thereafter for a median of 91 months (range, 0.2 to 109 months), 13 patients (19%) developed a second neoplasm. Six neoplasms were of hematopoietic origin, whereas the remaining seven were adenocarcinomas. The expected number of second tumors in this cohort is three (based on calculations from the National Cancer Institute's SEER data), so the excess frequency (observed:expected) is 4.33. However, the excess frequency is even greater for the hematopoietic neoplasms; the expected frequency is 0.15, whereas six hematopoietic tumors occurred, for an observed:expected ratio of 40. In general, the second neoplasms have behaved aggressively, and the median survival after diagnosis of the second neoplasm was only 8.8 months. Although we cannot entirely exclude the possibility that IFN therapy has some direct oncogenic effect, we suspect that increased frequency of second tumors is related to prolonged survival of patients who are immunocompromised because of HCL and thus prone to develop second tumors. If so, the frequency of second neoplasms in patients with HCL may be even greater in the future with continued improvements in therapy.