Clinical value of assaying tumor supplied group of factor/tumor specific growth factor in patients with solitary pulmonary nodule

Abstract

Objective: This pilot study was designed to evaluate the clinical value of assaying tumor supplied group of factor/tumor specific growth factor (TSGF) in solitary pulmonary nodule (SPN).

Patients and methods: The study was conducted from March 2007 to September 2010 and included 33 patients with SPN and 28 healthy volunteers. TSGF was assayed in preoperative serum, intraoperative pleural lavage fluid (IPLF), and postoperative serum.

Results: At operation, 20 patients were diagnosed with malignancy and 13 patients were diagnosed with nonmalignancy and placed in group A and group B, respectively. In group A, pathologic staging demonstrated 8 patients (group A1) with stage T1N0M0, 7 patients (group A2) with stage T1N1M0 and 53 patients (group A) with stage T1N2M0 disease. In group B, 8 patients were diagnosed with tuberculoma (group B1) and 5 patients were diagnosed with inflammatory pseudotumor (group B2). Before operation, levels of TSGF in peripheral blood were significantly higher in group A compared with group B and the control group (98.8 ± 29.9 vs. 62.1 ± 24.9 and 50.1 ± 17.9, Student-Newman-Keuls test; P < .05). The percentage of patients with positive serum TSGF results was significantly higher in group A than in group B or the control group (90.0% vs. 30.8% and 17.9%, χ(2) test; P < .05). With respect to the diagnostic value of serum TSGF in malignant SPN, we found sensitivity to be 90%, specificity to be 69.2%, positive forecast rate to be 74.5%, negative forecast rate to be 87.4%, and accurate diagnosed rate to be 79.5%. The TSGF level in IPLF in group A was significantly higher than that in group B (132.2 ± 51.9 vs. 84.6 ± 12.6, Student t test, P < .05). Additionally, TSGF in group A2 and group A3 was significantly higher compared with group A1 (162.2 ± 52.3 and 176.4 ± 17.8 vs. 100.2 ± 35.8, Student-Newman-Keuls test; P < .05). Postoperative serum TSGF in the patients diagnosed with lung cancer decreased significantly after operation. TSGF returned to a normal threshold level (71 U/mL) in the sixth month postoperatively. In addition, there was no appreciable change in the patients in group B.

Conclusion: Serum TSGF is conducive to discriminating between benign and malignant features of SPN. Additionally, investigation of IPLF TSGF can potentially offer a new approach to predict the existence of lymph node metastases.