Immunohistochemistry- Not As Sensitive As Expected For Detecting Bone Marrow Micrometastases In Cases Of Epithelial Malignancies?

Abstract

Background: Bone marrow is the most common site of metastases of epithelial malignancies from breast, lung, colon, prostate, ovaries and endometrium. These have poor prognosis as early tumor cells dissemination to bone marrow leads to poor treatment response. Bone marrow involvement by tumor cells can be seen on microscopic bone marrow examination and confirmed by immunohistochemistry. In this prospective observational study, we plan to analyze the incidence of bone marrow dissemination in epithelial malignancies and estimate the utility of immunohistochemistry in detecting micro metastases and correlate it with other clinicopathological parameters.Methods: clinical details and complete hematological workup was done in31 new cases of epithelial malignancies during our study period of one year. Bone marrow aspiration, bone marrow biopsy and clot section were done and analyzed morphologically and immunohistochemically using CK 7 and CK 20.Result: out of a total of 31 cases of epithelial malignancies, 2 cases of prostate carcinoma showed positive metastatic cell cluster and 2 cases of breast carcinoma and 1 case of lung carcinoma showed dispersed atypical cells in bone marrow. Conclusion:Immunohistochemistry did not show any observed benefit than routine microscopy in diagnosing the bone marrow metastases. Small sample size and lack of ancillary techniques like polymerase chain reaction(PCR) are drawback in the diagnosis of isolated tumor cells, micro metastases and confirmation of the results obtained on immunohistochemistry. Extensive studies are required to elucidate the pathogenetic pathway and clinical implications of bone marrow metastatic cells for the diagnosis, staging and treatment of epithelial malignancies.