Bone marrow involvement in esophageal cancer patients who underwent surgical resection

Behaviors of esophageal cancer are different according to the geographic distribution. The prevalence of bone marrow involvement in patients with esophageal cancer has been shown to be between 40% and 90%, but clinical correlation is unknown. The aim of this study is to determine the rate of bone marrow involvement in patients with esophageal cancer in the northeast of Iran and its relationship with clinicopathologic findings of the tumors.

A total of 43 patients with esophageal cancer, who were candidates for esophagectomy (without neo-adjuvant chemotherapy), were enrolled in this study from 2007 to 2009. Bone marrow samples derived from rib bone were stained with hematoxylin and eosin (H&E) to distinguish tumoral cells, and cytokeratin immunohistochemistry (CKIHC) was used to determine micrometastasis. The correlation of the results was studied with the histopathologic indices of primary tumor (T (tumor), N (node) and length of tumoral involvement and grading) as well as characteristics of the patients (sex and age).

The mean age was 64 (57-70) years and the M/F ratio was 2.9. As many as 38 patients (88.4%) had squamous cell carcinoma and five patients (11.6%) had adenocarcinoma. In nine cases (20.9%), the H&E test, and, in 13 cases (30.2%), the CKIHC evaluation was positive. Statistically, there was no relationship between the pathologic type and the stage of T with the H&E study and CKIHC test, respectively. On the other hand, a significant meaningful correlation was found between microscopic bone marrow involvement as well as mediastinal lymph node involvement and grade of the tumor.

Bone marrow involvement incidence was low in our geographic area. According to our study, bone marrow involvement in esophageal cancer is related to differentiation grade and mediastinal lymph node involvement.