Objective: The most common type of leukemia in adults; chronic lymphocytic leukemia (CLL), which is detected in 25% of all leukemias. In epidemiological studies in western societies, its incidence was found to be 4/100,000. CLL is an advanced age disease and its incidence increases with age. While some of the patients are followed up asymptomatically and with lymphocytosis without any treatment indications, others may show aggressive clinical course, appear with cytopenia and cause chemotherapy indications. Suppression of immunity and B cell dysfunction in CLL can cause secondary malignancies. In a much rarer group of patients, the diagnosis of CLL and solid organ cancer is made simultaneously. In such cases, pathological or cytogenetic common mechanisms or common risk factors such as smoking and radiation may play a role in etiology. We also wanted to present the coexistence of small cell lung cancer (SCLC) and CLL, which are rarely diagnosed simultaneously, and may contribute to the literature.
Case report: In the examination of a 82-year-old male with a history of smoking 30packs/year, who suffered from ongoing loss of balance for approximately 1 month, an irregular limited mass with a size of 3×2cm was detected in the upper left lobe. The fine needle biopsy result from the mass was reported as SCLC and was considered Stage 3 in the evaluation. The patient was started on cisplatin 75mg/m2+etoposide 100mg/m2 chemotherapy protocol treatment by department of pulmonary diseases. During the diagnosis process, the patient, who was found to have had long-standing lymphocytosis, was also asked for flow cytometry examination upon monitoring of mature lymphocyte infiltration and basket cells in the peripheral smear examination. In flow cytometric examination, CD5, CD19, CD20, CD23 were positive and CD10, CD103 were negative and these findings were reported as B-lymphoproliferative disease (CLL). The patient, who was evaluated as stage 1 CLL with detailed blood tests and imaging, was followed up without treatment. During follow-up, in the evaluation of the patient with deep anemia, the direct coombs test was positive (IgG) and the biochemical markers were compatible with hemolysis, 60mg/day (1mg/kg/day) methylprednisolone treatment was started for the patient who was diagnosed with autoimmune hemolytic anemia. With the initiation of corticosteroid therapy, a significant increase in both hemoglobin value and improvement in hemolysis parameters of the patient was observed and treatment was continued by decreasing the dose. The patient, whose steroid treatment is completed and hemogram parameters are monitored within normal limits, is followed up without treatment by the hematology department in terms of CLL. At the same time, the third cycle of chemotherapy has been completed with the diagnosis of SCLC and is followed by the department of pulmonary diseases.
Conclusion: CLL constitutes a high risk factor for many solid tumors such as lung, breast, colon and prostate cancer. In a study in which 4.869 CLL patients were screened for secondary malignancy, 33 lung cancers were detected and SCLC was 6% among all lung cancers.
