Nodular thickening of interlobar fissures: an early manifestation of malignant mesothelioma: a case report

Our plain-English summary of Nodular thickening of interlobar fissures: an early manifestation of malignant mesothelioma: a case report, by S. Bandoh, J. Fujita, Y. Fukunaga, et al (Japanese Journal of Clinical Oncology, 2001).

The study

• Authors: S. Bandoh, J. Fujita, Y. Fukunaga, S. Ohtsuka, K. Susaki, Y. Yang, S. Kobayashi, J. Takahara
• Journal: Japanese Journal of Clinical Oncology
• Published: 2001;31(2):82-5
• Type of article: Case report
• Cited by: 5 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Two men with occupational exposure to asbestos were admitted to our hospital with minute pleural changes on their chest CT image. Conventional computed tomography (CT) scans of the chest showed slightly thickened interlobar fissures and a small amount of pleural effusion. In addition, high-resolution CT showed small nodular opacities on interlobar fissures. There were no intrapulmonary mass shadows, pleural plaques or other extrapulmonary mass shadows. These roentgenographical findings were very similar to each other. Hyarulonic acid values obtained from their pleural fluid were extremely high. Finally, we diagnosed them as having malignant mesothelioma using an immunocytochemical technique and electronmicroscopy. We conclude that HRCT is helpful in the diagnosis of malignant mesothelioma, particularly in its early manifestation such as nodular opacities of interlobar fissures.

In plain English

This article was a report on two patients treated at Kagawa Medical University in Japan. Both were men with long occupational exposure to asbestos: a 56-year-old car mechanic exposed for 38 years and a 61-year-old maker of asbestos tubes exposed for 40 years. Conventional CT scans of the chest showed slightly thickened interlobar fissures (the thin membranes between lung lobes) and a small amount of pleural effusion (fluid around the lung). High-resolution CT (HRCT) also showed small nodular opacities on these fissures. Neither man had lung masses or pleural plaques. Fluid drawn from around the lungs had hyaluronic acid levels of 320 000 ng/ml in the first man and 540 000 ng/ml in the second. The stated normal value was below 100 000 ng/ml. In the first man, metastatic adenocarcinoma was suspected at first. Immunocytochemistry and electron microscopy led to a diagnosis of malignant mesothelioma in both men. Neither man's disease responded to chemotherapy. The authors concluded that HRCT is helpful in diagnosing malignant mesothelioma, particularly in its early stage. They said it was unclear whether HRCT can tell early mesothelioma apart from metastatic adenocarcinoma.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (two cases)
• Who was studied: Two men, aged 56 and 61, admitted to Kagawa Medical University hospital, Japan; both had occupational asbestos exposure and were smokers or former smokers
• Exposure: Occupational asbestos exposure: car mechanic for 38 years (case 1); maker of asbestos tubes for 40 years (case 2). No fiber type was named.
• Main results:
  • In both men, HRCT showed small nodular opacities on the interlobar fissures, and there were no lung masses, pleural plaques or other masses; conventional CT showed only slightly thickened fissures and a small effusion
  • Both men had no intrapulmonary mass shadows, pleural plaques or other extrapulmonary mass shadows
  • Case 1 pleural fluid: CEA 0.5 ng/ml (normal below 2.5 ng/ml) and hyaluronic acid 320 000 ng/ml (normal below 100 000 ng/ml)
  • Case 2 pleural fluid: CEA 1.2 ng/ml and hyaluronic acid 540 000 ng/ml
  • In case 1, metastatic adenocarcinoma was first suspected from cytology, but immunocytochemistry and electron microscopy led to a diagnosis of malignant mesothelioma
  • Neither patient responded to chemotherapy: case 1 showed no response, and in case 2 the tumor progressed
• The authors' conclusion: The authors concluded that HRCT is helpful in diagnosing malignant mesothelioma, particularly early on, when it appears as small nodular opacities of the interlobar fissures
• Limitations the authors state:
  • The authors stated that it is unclear whether HRCT can distinguish early-stage malignant mesothelioma from metastatic adenocarcinoma, and that further studies are needed

Topics

The National Library of Medicine indexes this study under subjects our site covers: Asbestosis, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Mesothelioma, Occupational Exposure, Pleural Effusion, High-Resolution CT (HRCT), Pleural Plaques.

Related studies

• Visceral pleural thickening in asbestos exposure: the occurrence and implications of thickened interlobar fissures — S.D. Rockoff, E. Kagan, et al. (1987)
• Thickening of pulmonary interlobar fissures: exposure-response relationship in crocidolite and amosite miners — A. Solomon, L.M. Irwig, et al. (1979)
• CT demonstration of interlobar fissure calcification due to asbestos exposure — S.D. Rockoff (1987)
• Localized malignant pleural mesothelioma arising in the interlobar fissure: a unique surgical case masquerading clinicopathologically as primary lung adenocarcinoma — X. Guo, J. Watanabe, et al. (2019)
• A Man in His 20s With Cough, Unilateral Pleural Effusion, and Nodular Pleural Thickening — M.A. Sonnick, S. Weisman, et al. (2019)
• Calcified plaque in the superior portion of the major fissure. An unusual manifestation of asbestos exposure — S.B. Rupp, H. Jolles (1989)

Browse more research in Japanese Journal of Clinical Oncology, or return to medical research.