A thirty-eight year old woman, presented with left lateral back-ache, night fever and cough. Chest X-ray revealed a well-demarcated round lesion in the left upper lung. Thoracotomy was performed and the mass was removed from the left upper lung. The extracted specimen, measuring 3 x 2,5 x 2 cm was fragile in consistency. The cut surface showed gray whitish nodular pattern with some hemorrhagic areas. Histopathological picture showed lobules of cartilage. The lobules were separated by clefts and tubules, lined by pseudostratified respiratory epithelium. Based on these findings, the diagnosis of hamartoma was made (Figure 1
Short-term cultures were initiated from fresh tissue in RPMI 1640 (Irvine Scientific) with HEPES buffer supplemented with foetal calf serum (10%) (Irvine Scientific), L-Glutamine (Irvine Scientific), penicilline-streptomycin (Irvine Scientific), epidermal growth factor (Sigma) and insulin (Sigma). After 3-7 days, the cultures were exposed to colcemid (0,01 mg/ml) (Gibco) for 4 hours and harvested by hypotonic treatment in 0,06 M KCL (Merck) and repeated fixations in methanol:acetic acid (3:1). The slides were incubated at 37oC for 3 days and then G-banded with Giemsa (Merck) stain. Thirteen out of the twenty-five metaphases analysed showed the following karyotype 46,XX, add  (p21) (Figure 2). The remaining cells were normal. Also nonclonal abnormalities were found as del  (q21q29), del  (q32q36).
Test DNA was obtained from paraffin-embedded tumor sample scraped from hamartoma cell areas with sterile scalpel using modified single step DOP-PCR (Degenerate Oligonucleotid Primed-Polymerase Chain Reaction) [3-5]. This first-step DOP-PCR amplified DNA of test and normal human (female) DNA were labeled with Spectrum Green-dUTP and Spectrum Red-dUTP (Vysis Co.) respectively by second-step DOP-PCR. Hybridization was performed as described earlier . Briefly, test DNA and normal human DNA were hybridized to slides of metaphase cells from the blood of a healthy donor (female). Following hybridization for 2 days, slides were washed, and chromosomes were counterstained with DAPI (4,6-diamino-2-phenylindole, 200 ng/ml). Digital image analysis; using PSI (Perceptive Scientific International, LTD) Workstation image processing and evaluation were described in detail before . Losses and gains of chromosomal regions in this patient obtained as an outcome of CGH (Figure 3) are shown in Table 1.
Figure 1: Microphotograph of the lesion of showing lobules of cartilage separated by clefts lined by respiratory epithelium
Figure 2: Karyotype of the patient
Figure 3: Summary of all chromosomal gains and losses identified in a case of hamartoma. Vertical lines on the right side and left side of chromosome indicate a gain and loss of genetic material, respectively
Table 1: Comparative genomic hybridization results of a case with hamartoma