[Prognosis of inoperable non-small cell bronchial cancer]. / Prognose ved inoperabel ikke-småcellet bronkialcancer.

The article describes a retrospective study of the prognosis for 450 patients with inoperable non-small cell lung cancer discharged during the period 1970 to 1979. 81% of the patients were males. The predominant cell type was squamous cell carcinoma. One out of seven patients was inoperable because of poor cardiorespiratory function, six out of ten because of mediastinal metastases. Median survival was six months and was related both to staging of the tumor and to cell type. The prognosis was worst for patients with adenocarcinoma. Only 8% of the 450 patients were alive after two years. Specific and palliative therapy had a minor effect on median survival. Controlled clinical trials can probably settle whether an extension of the criteria for surgical treatment can improve the prognosis of this large group of patients.

Questionnaire reliability and validity for aluminum potroom workers.

As a part of a study on the respiratory symptoms of aluminum potroom workers, the reliability of a self-administered questionnaire and an interview questionnaire was studied with the use of 261 and 49 employees, respectively. The validity of the self-administered questionnaire (134 persons examined) and the interview questionnaire (90 persons examined) was assessed in a comparison of the statements with the case histories. The reliability of the self-administered questionnaire was fairly high, the kappa coefficient ranging from 0.58 to 0.83, while the reliability of the interview questionnaire varied from -0.03 to 0.45. The same pattern was present with regard to validity, as the self-administered questionnaire showed the highest mean sensitivity, specificity, and agreement in a comparison with the case histories. The self-administered questionnaire seemed to discriminate well between symptomatic and asymptomatic individuals, whereas supplemental information about symptoms, as obtained by a standardized interview questionnaire, appeared to be less valid.

Changes in plasma and red cell volumes during exposure to high altitude.

Training at moderate altitude has been used by athletes to improve the performance at sea level. Not all athletes benefit from altitude training, and there also has been some doubt as to whether red cell volume increases in all subjects. Ten members of the Norwegian Everest Expedition 1985 took part in the present study. Plasma volume was determined by isotope dilution, using 125I-albumin. By simultaneous measurement of hematocrit the total blood volume and red cell volume were calculated. Measurements were done in Oslo (sea level) before departure, and in Base Camp (5300 m) four weeks later. The mean altitude during these four weeks was 4100 m. Red cell volume increased in all participants, and excessively in two of them. Since plasma volume decreased in four subjects, the change in total blood volume was less consistent. In one climber dehydration led to a decrease in total blood volume. While a significant correlation was found between maximal oxygen uptake and red cell volume at sea level, the hematologic response to altitude seemed independent on physical fitness. In one climber the erythropoietic response was so excessive (more than 50% increase in red cell volume), that he had to be hemodiluted.

Bronchial challenge: interpretation of readings.

Bronchial reactivity as tested in vivo reflects to some extent the responsiveness of smooth muscle in the lower airways. The in vivo reactivity is often presented in terms of PC20 (provocation concentration leading to a 20% fall of FEV1), an index that is supposed to provide condensed information of the general dose/response relationship by a continuous variable. However, expressing the fall in relative terms is not strictly logical, as the random experimental error of FEV1 shows a homoschedastic distribution. Furthermore, PC20 becomes mathematically unstable in cases with a slight response and can be determined with reasonable precision only when the observed fall is close to 20% or more. When a small number of highly differing dose levels are used in clinical challenge testing, the results should rather be presented as the maximum, absolute change of FEV1 obtained at a specified dosage.

High-dose intravenous methylprednisolone pulse therapy as initial treatment in cryptogenic fibrosing alveolitis. A pilot study.

Ten patients with fibrosing alveolitis were treated in a simple random design initially with either a high dose of methylprednisolone (5 patients) or a conventional dose of prednisolone (5 patients) followed by a maintenance dose of 30 mg prednisolone daily. The patients were followed for 6 weeks. No significant (p greater than 0.05) differences were observed between patients with high and low initial dose of glucocorticosteroids, as regards forced vital capacity, transfer factor for carbon monoxide or symptom scores after 3 and 6 weeks of treatment. After 6 weeks the dyspnoea score and the 67Ga uptake decreased, on average, by 74 and 85%, respectively, while forced vital capacity and transfer factor increased by 15 and 29%.

Influence of matching volume on reproducibility of maximal expiratory flow-volume curves.

We examined the influence of "matching volume" on intrasubject variability of the descending limb of maximal expiratory flow-volume (MEFV) curves on air and helium-oxygen (He) in 18 healthy subjects and 28 patients with airflow limitation. Duplicate forced expirations were analysed according to four methods of alignment. With the first method, flows corresponding to identical percentiles of separate FVC (SEPVC) were compared. With the remaining three, we aligned curves at TLC, mid-vital capacity (VC50) and RV, respectively, for comparison of: a) flow at identical percentiles of the averaged FVC and b) expired volume at identical percentiles of the averaged peak flow. In healthy subjects, variability of flow at 50% and 75% of expired FVC (FEF50 and FEF75) did not change significantly with method, except that FEF75 on air varied more with method SEPVC than with VC50. In airflow limitation, FEF75 was significantly less reproducible when curves were matched at RV than at TLC, both on air and He. Over the latter part of expiration, an arbitrary index of variability of flow-defined volume also indicated that method RV gave the poorest precision in patients. We conclude that selection of matching volume does not influence the variability of MEFV-curves in health. In airflow limitation, however, TLC appears to be the most reliable volume for alignment.

Moments analysis in clinical spirography--a cul-de-sac?

Mean transit time (MTT) and some higher amounts of the forced expiratory curve were calculated at routine spirography in 190 patients with respiratory disorders. MTT was closely related to traditional indices of airflow obstruction. Within duplicates, both MTT and an index of dispersion of transit times depended strongly on expiratory time and showed a correspondingly poor repeatability. An additive, exponential model of log normally distributed transit times could, for numerical reasons, be adapted in 61 patients only and led in these to a further impairment of precision. A corresponding model of discrete type, universally applicable by optimization, regenerated volume/time curves inaccurately. None of these infinite models proved able to eliminate the influence of expiratory endurance on transit time characteristics. This finding indicates that forced expiratory curves do not in general behave like composite exponentials.

Survival in lung cancer after surgery.

In 1053 patients hospitalized for primary lung cancer the overall crude survival rate (5 years) was 15.5%. Prognostically favourable indices were: absence of clinical symptoms (27% survival) and a peripheral site of tumour in the lung (28% survival). Duration of symptoms, when present, had no consistent influence on prognosis. Resection could be done in 419 cases. In this group the 5 years survival rate was strongly related to the extent of surgery and the completeness of resection. Cases with a radical lobectomy had a survival rate of 52% against 9% only in patients with a pneumonectomy that might not have been radical. Of 33 cases of resected small cell anaplastic cancer, 10 survived more than 5 years. This unexpectedly high survival rate persisted after revision of the histological typing and may justify an active surgical attitude even in this group of patients. Although hardly decisive in this context, confusion between the comprehensive term small cell carcinoma and its subtype, oat cell cancer, should be avoided.

Lung cancer. Symptoms, signs and diagnostic criteria.

A consecutive hospital series of 1 053 patients treated for lung cancer during the period 1962 through 1971 has been studied. Clinical symptoms were present more often in men than in women and in 42% symptoms had been noted more than 6 months prior to the diagnosis. Peripheral tumours gave less symptoms than central ones. Although in 22% of the patients the tumour was discovered on a chest film in the absence of relevant symptoms, 12% only had been detected by regular mass X-ray screening. More than 40% of the peripherally located tumours were clinically silent. Squamous cell and anaplastic small cell cancers were predominantly centrally located (80 and 90%, respectively) against 65% and 74% for adenocarcinomas and undifferentiated large cell tumours.

Lung cancer. Treatment and early results.

Of 1053 patients with primary cancer of the lung, 549 (52%) underwent thoracotomy and 40% a presumably radical resection. Lobectomies were performed in 227 patients (41% of those operated), pneumonectomy in 160 (29%). Early mortality (death within 30 days) was 5.5% with the highest figure (11%) after pneumonectomy, 5% after explorative thoracotomy and 3% after lobectomy. Cardiorespiratory failure and myocardial infarction occurred in 19 (3.5%) of the operated cases and were responsible for 14 early deaths. Bronchopleural fistula developed in 11 patients. Of 874 morphologically classified tumours, squamous cell composed 45%, undifferentiated large cell 17%, small cell anaplastic 14%, adenocarcinoma 19%, carcinoid 2% and others 3%. Of 21 tumours typed as small cell anasplastic prior to therapy, six were differently classified at the later (postoperative/postmortal) stage.