Re-evaluation of diagnostic parameters is crucial for obtaining accurate data on idiopathic pulmonary fibrosis.

BACKGROUND: The FinnishIPF registry is a prospective, longitudinal national registry study on the epidemiology of idiopathic pulmonary fibrosis (IPF). It was designed to describe the characteristics, management and prognosis of prevalent and incident IPF patients. The study was initiated in 2012. METHODS: We present here results limited to five university hospitals. Patients with IPF were screened from hospital registries using ICD-10 diagnosis codes J84.1 and J84.9. All patients who gave informed consent were included and evaluated using novel diagnostic criteria. Point prevalence on the 31(st) of December in 2012 was calculated using the reported population in each university hospital city as the denominator. RESULTS: Patients with ICD-10 codes J84.1 and J84.9 yielded a heterogeneous group - on the basis of patient records assessed by pulmonologists only 20-30 % of the cases were IPF. After clinical, radiological and histological re-evaluation 111 of 123 (90 %) of patients fulfilled the clinical criteria of IPF. The estimated prevalence of IPF was 8.6 cases/100 000. 60.4 % were men. Forty four percent of the patients were never-smokers. At diagnosis, the patients' mean age was 73.5 years and mean FVC was 80.4 % and DLCO 57.3 % of predicted. CONCLUSIONS: Our results suggest that hospital registries are inaccurate for epidemiological studies unless patients are carefully re-evaluated. IPF is diagnosed in Finland at a stage when lung function is still quite well preserved. Smoking in patients with IPF was less common than in previous reports.

Tissue MMP-2 and MMP-9 [corrected] are better prognostic factors than serum MMP-2/TIMP-2--complex or TIMP-1 [corrected] in stage [corrected] I-III lung carcinoma.

Matrix metalloproteinases (MMPs) are involved in tumor growth and spreading. Here, we investigated the tumor immunoreactive protein of MMP-2, MMP-9 and TIMP-1 as well as the levels of circulating total TIMP-1 and MMP-2/TIMP-2-complex as prognostic factors in lung cancer patients. The material included 59 patients, 30 with a squamous cell carcinoma, 21 with an adenocarcinoma and eight with other histology. Circulating antigens were measured by ELISA assay and the protein expression in primary tumors was analyzed by streptavidin-biotin immunohistochemical staining using specific monoclonal antibodies. The strong positivity for MMP-2 or MMP-9 in tumor predicted poor prognosis. The 5-year survival rates were 83 or 85% in patients negative for MMP-2 or MMP-9, respectively. Only 17% of the patients with a tumor highly positive for MMP-2 and 43% of those with a high positivity for MMP-9 survived at that time (Cox regression P=0.042 for MMP-2 and log rank P=0.046 for MMP-9). On the contrary, strong tissue positivity for TIMP-1 demonstrated a tendency for a favorable survival, although the difference did not reach statistical significance. In patients with a squamous cell carcinoma Stage I, low serum TIMP-1 (or=300 ng/ml) associated with an increased survival rate, the 5-year survival being 81 versus 34% (log rank P=0.069) in patients with high or low serum levels for MMP-2/TIMP-2-complex, respectively. Tissue MMP-2 correlated to high expression of MMP-9 immunoreactive protein (P=0.003), but the serum levels of MMP-2/TIMP-2-complex or TIMP-1 did not correlate to the immunostaining of the corresponding tumors. We conclude that in lung carcinoma the best prognostic value is achieved by using immunohistochemistry for MMP-2 and MMP-9. In early disease, however, serum TIMP-1 or MMP-2/TIMP-2-complex could offer some further prognostic value.

Prospective population-based study on the survival of patients with lung cancer.

The purpose of this study was to evaluate the change, over 20 yrs, in the survival of lung cancer patients in a population-based study. Information on all patients with lung cancer in a defined geographical area during 1990-1992 (n=602) was prospectively gathered. The survival of these patients was assessed and also compared with the results of a similar study in the same area during the years 1968-1971 (n=446). The 5-yr survival had improved during 20 yrs from 4% to 12%. The 5-yr survival of the patients with squamous cell carcinoma had increased from 6% to 16%, and adenocarcinoma from 4% to 19%, whereas the survival of small cell carcinoma had remained the same (2% and 3%, respectively). Even though the recent patients were older than those of the earlier series the proportion of surgically treated patients had remained the same (16% and 20%), but the 5-yr survival of patients who had been operated on had increased significantly from 23% to 48%. The differences in survival in the second cohort (1990-1992) between histological types (Chi-squared logrank=59.2), tumour, node, metastasis stages (Chi-squared logrank=199.6), symptomatic stages (Chi-squared logrank=120, p<0.001) and treatment (Chi-squared logrank=277) were significant. Based on this study the independent prognostic factors for better survival of lung cancer patients are tumour, node, metastasis stages I and II, surgical treatment and Feinstein's symptomatic stages I and II.

Elevated serum levels of type I collagen degradation marker ICTP and tissue inhibitor of metalloproteinase (TIMP) 1 are associated with poor prognosis in lung cancer.

PURPOSE: The aim of this study was to evaluate the correlation between type I collagen degradation marker ICTP, MMP (matrix metalloproteinase)-9, and tissue inhibitor of metalloproteinase (TIMP)-1 and to compare their value as prognostic factors in lung cancer. EXPERIMENTAL DESIGN: From the sera of 141 lung cancer patients, we assessed markers of type I collagen synthesis (PINP and PICP) and degradation (ICTP) by radioimmunoassays, and we assessed MMP-9 and its tissue inhibitor TIMP-1 by ELISA. There were 62 squamous cell carcinomas, 42 adenocarcinomas, 14 small cell carcinomas, and 23 cases with other histology. Seventeen of these patients had advanced disease. Sixty-seven patients had been operated on, 33 had received radiation therapy, 7 had received chemotherapy, and the rest had received other treatment combinations. RESULTS: We examined the relationship between these markers and found a correlation between ICTP and MMP-9 (r = 0.201; P = 0.01) or TIMP-1 (r = 0.415; P = 0.00). Elevated serum concentrations of ICTP (>5 microg/liter) and/or TIMP-1 (>300 ng/ml) correlated with poor prognosis. In univariate regression analysis, ICTP had prognostic value (odds ratio, 1.6462; P < 0.03): the patients with elevated serum concentrations of ICTP (>5 microg/liter) had a 64% higher risk of dying from lung cancer than did patients with opposite values. CONCLUSIONS: Our results indicated that ICTP and TIMP-1 are good prognostic markers in lung cancer. The association between serum MMP-9 and ICTP suggests that MMP-9 could play a role in the degradation of the extracellular matrix producing ICTP in this pathological situation.

An epidemiological study of lung cancer: history and histological types in a general population in northern Finland.

A prospective epidemiological study was conducted to assess the incidence, diagnosis, histology and surgical treatment of lung cancer in northern Finland. The results were compared with those obtained in a similar survey 20 yrs earlier. Most of the patients with a suspected lung tumour were interviewed (72%) and the information was combined with that obtained from the national cancer registry. All pathological specimens were re-evaluated by a pathologist. A total of 602 new lung cancer cases (85% male, 15% female) were diagnosed during the years 1990-1992, the annual incidence per 100,000 being 63 for males and 9.5 for females. The number not reported to the Finnish Cancer Registry was low (<1%). Lung cancer was confirmed histologically in 381 cases (63%) and in addition cytologically in 135 cases (23%). Squamous cell carcinoma was the most common histological type (40%), the proportion of adenocarcinoma being 26%, small cell carcinoma 24% and large cell carcinoma 4%. The incidence of lung cancer had decreased significantly among males (from 87 to 63 per 100,000) compared with 20 yrs earlier but had increased among females (from 4.1 to 9.5), chiefly on account of adenocarcinoma. The findings of this prospective study show an increase in the incidence of lung adenocarcinoma among females, a histological type which is less closely related to smoking than the other cancers. This suggests that other risk factors may play an increasing role in the aetiology of lung cancer.

Benign intrathoracic tumours. A population survey in northern Finland.

Benign intrathoracic tumours are uncommon, but their occurrence in unselected populations is poorly defined. We reviewed all cases of suspected intrathoracic tumour in a population (440,000) in northern Finland during 1990 through 1992. Diagnostic investigations included fiberoptic bronchoscopy and computed tomography in all cases. Of the 653 intrathoracic tumours, 36 were benign. The male/female ratio in these 36 cases was 1.25; the mean age was 54 years. Twenty-three of the lesions were symptomless, found at health check or examination for other disease. Bronchoscopy did not confirm the diagnosis of any benign tumour. Thoracotomy was considered necessary in most cases and histologic diagnosis was therefore available in 24 (67%). Hamartoma was the most common benign lung tumour. This prospective study in an unselected population confirms previous findings in surgical series concerning benign intrathoracic tumours and their histology.

p53 protein accumulation in lung carcinomas of patients exposed to asbestos and tobacco smoke.

Primary lung carcinomas often carry mutations in the p53 tumor suppressor gene. Most of these mutations alter the conformation of the p53 protein into a more stable phenotype that makes it immunohistochemically detectable. Asbestos is a carcinogen that can cause deletions in chromosomes and possibly also gene mutations. In this study we examined 70 primary lung carcinomas for p53 protein accumulation using a polyclonal antihuman p53 antibody, CM-1. Patients were interviewed about their occupational and smoking history and classified according to their anamnestical asbestos exposure. Presence of asbestos bodies (AB) was evaluated from histologic samples of peripheral nontumorous lung tissue using both 5-microns-thick sections stained with Perls' iron and 30-microns-thick unstained sections. Abnormal accumulation of p53 protein was found in 36 tumors (51%), more often in patients exposed to asbestos than in patients without exposure (67% versus 40%, p = 0.027). Significant association was also noticed between the accumulation of p53 and the asbestos content of lung tissue: 35% of the p53-positive patients had more than one AB/cm2 compared with 14% of p53-negative cases (p = 0.046). Patients with strongly p53-positive tumors were heavier smokers (57.2 +/- 38.2 pack-years) than patients with p53-negative or lightly positive tumors (38.9 +/- 19.9 pack-years) (p = 0.017). Our findings indicate that both asbestos exposure and heavy smoking can cause abnormal p53 protein accumulation suggestive of mutated p53.