Staging procedures in small cell lung cancer

Detection of bone marrow metastases of small cell lung cancer with magnetic resonance imaging: early diagnosis before destruction of osseous structure and implications for staging

Small cell lung cancer (SCLC) frequently metastasizes to bone and bone marrow. Skeletal scintigraphy and bone marrow cytology or biopsy, are incorporated into the staging procedures to examine these organs. However, skeletal scintigraphy is not highly specific to metastases, and only one or two bone marrow sites can be examined by cytology or biopsy. We have already reported that magnetic resonance imaging (MRI) could improve the sensitivity in detecting bone marrow metastases. The result of the bone marrow MRI was an independent prognostic factor of SCLC patients [9]. In the present study, we analyzed the results of skeletal scintigraphy and bone marrow aspiration with special reference to the results of MRI examination. We also analyzed the relationship between bone marrow lesions and bone lesions. For this purpose, we visualized bone marrow metastases with MRI and determined their anatomical locations and sizes. Approximately half of bone marrow lesions stayed in bone marrow during follow-up period ranging from 57 to 154 days, whereas about half of them were accompanied by hot spots in follow-up skeletal scintigraphy, which indicates the destruction of osseous structure. Additionally, 87.5% of osteolytic changes that newly appeared in skeletal scintigraphy were preceded by adjacent bone marrow lesions. All new lesions that appeared in follow-up skeletal scintigraphy within 3 months after the initial presentation had the preceding bone marrow lesions. These results mean that almost all lesions in skeletal scintigraphy derived from bone marrow metastases. Furthermore, appreciable volume of cancer cells is present in bone marrow before osteolytic changes appear in skeletal scintigraphy.

Effect on prognosis of bone marrow infiltration detected by magnetic resonance imaging in small cell lung cancer

The staging system of limited disease (LD) and extensive disease (ED) is widely used and has been shown to provide useful prognostic information in cases of small cell lung cancer (SCLC). However, accurate examinations are necessary for correct staging. In this report, we evaluated the clinical usefulness of magnetic resonance imaging (MRI) of bone marrow in SCLC. 37 patients with LD by standard staging and 41 with ED were examined with bone marrow MRI. Results of bone marrow MRI did not influence the choice of treatment in patients with LD. For subsequent analysis, patients with LD were divided into two groups: patients in whom bone marrow infiltration was detected with MRI (MRI-positive LD group) and those in whom it was not (MRI-negative LD group). Focal or diffuse metastases to bone marrow were detected with MRI in 46% (36/78) of all patients and 35% (13/37) of LD patients. The response rates to treatment in patients with MRI-positive LD were lower than those in patients with MRI-negative LD (P = 0.006). The survival of patients with MRI-positive LD was worse than that of MRI-negative LD (generalised Wilcoxon test: P = 0.0157), and closer to that of ED. Multivariate analyses using a Cox model that included the result of bone marrow MRI, performance status, chemotherapy regimen, radiotherapy and serum lactose dehydrogenase (LDH) level showed that the result of bone marrow MRI remained a prognostic factor in SCLC patients with limited disease. Bone marrow examination with MRI is useful for better staging of SCLC. According to our analysis of response rates and survival, MRI-positive LD should be considered a type of ED.

The impact of abdominal computerized tomography on the pretreatment staging and prognosis of small cell lung cancer

One hundred six patients with small cell lung cancer (SCLC) were prospectively evaluated with regard to the prognostic impact of abdominal CT-scan in the pretreatment staging when compared to ultrasonography of the abdomen. Staging based on abdominal ultrasonography (US) plus bilateral bone marrow examinations gave as a result that 47 patients had extensive disease (ED) (44%). Seventeen patients with proven ED at time of referral were not included in this study. Abdominal CT-scan was performed in 76 of the 106 patients. Thirty patients of these 76 patients (39%) were classified as having ED after staging including US, but abdominal metastases were disclosed in another ten patients at the subsequent CT-scan. Liver metastases seen in two patients at ultrasonography were overlooked on the CT-scans. Median survival of the 36 patients classified as having limited disease (LD) after both procedures was 458 days, which was significantly better compared to 330 days for the ten patients with stage migration from LD to ED based on CT-scan, (p less than 0.05) and compared to 242 days in the 30 patients with ED demonstrated by both US and CT-scans (p less than 0.05). The prognostic impact of the CT-scan was further investigated in a multivariate analysis (Cox). Stage disease, performance status, LDH and alkaline phosphatase were significant prognostic factors in a proportional hazards model based on the original 106 patients. Patients in the best prognostic group were characterized by LD, good performance status (0-1) and normal LDH and alkaline phosphatase serum values. This group consisted of 22 patients (21%).(ABSTRACT TRUNCATED AT 250 WORDS)