Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy

Our plain-English summary of Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy, by S. Hasegawa, N. Kondo, S. Matsumoto, et al (International Journal of Clinical Oncology, 2012).

The study

• Authors: S. Hasegawa, N. Kondo, S. Matsumoto, T. Takuwa, M. Hashimoto, H. Orui, S. Fukuda, K. Yoneda, Y. Okumura, N. Tsubota, K. Fukuoka, I. Torii, T. Tsujimura, T. Nakano
• Journal: International Journal of Clinical Oncology
• Published: 2012;17(1):33-9
• Type of article: Review
• Cited by: 8 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Malignant pleural mesothelioma (MPM) remains suffering poor prognosis in spite of recent diagnostic and therapeutic progress. Although there is currently no established evidence, early diagnosis and early intervention may play a key role to improve prognosis of MPM, similarly to other malignancies. As pleural effusion is usually the first clinical sign of MPM, pleural effusion cytology is often the first diagnostic examination to be carried out. Since the sensitivity of pleural effusion cytology is approximately 60%, however, false-negative diagnosis is given to almost half of true MPM patients at this clinical step. One practical way to reduce the number of misdiagnosed MPM is to encourage performing thoracoscopic pleural biopsy unless definitive diagnosis other than MPM is established. There still remain a considerable number of patients with radiological/thoracoscopic T0 MPM who are misdiagnosed with nonspecific pleuritis after a complete investigation including thoracoscopic biopsies. Such patients will turn out to be malignant during follow-up period, although they have the best opportunity for long-term survival if only early therapeutic intervention is given. Currently, we are performing diagnostic total parietal pleurectomy in highly selected patients, who are characterized with strong clinical suspicion, positive pleural effusion cytology but uncertain pathological diagnosis, excellent cardiopulmonary reserve, and with written informed consent for highly invasive diagnostic surgery for pathologically unproven disease.

In plain English

This review article, by surgeons, physicians and pathologists at Hyogo College of Medicine in Japan, discussed how to diagnose and treat very early malignant pleural mesothelioma that cannot be seen on chest X-ray, CT or PET scans or during thoracoscopy. The authors called this "T0" mesothelioma. Citing earlier reports, they noted that pleural fluid cytology had a mean sensitivity of about 60% and that a few small biopsies may not represent the whole pleura. They proposed stepwise testing: non-invasive tests and fluid cytology, then thoracoscopic biopsy of the parietal pleura from 3 sites. Some patients' biopsies showed atypical mesothelial cells but no fat invasion. For highly selected patients in this group, with strong clinical suspicion, positive fluid cytology, excellent heart and lung reserve and written consent, the authors described performing diagnostic total parietal pleurectomy. In one illustrated case, this surgery found nodules of 1 to 2 mm, and the case was diagnosed as epithelioid mesothelioma. The article did not report how many patients had the operation. The authors acknowledged an ethical barrier and said the operation should be done as a clinical trial.

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: Review article with a proposed diagnostic approach, illustrated by one representative case
• Who was studied: Patients with possible radiological/thoracoscopic T0 malignant pleural mesothelioma, meaning pleural effusion without visible tumor. Diagnostic total parietal pleurectomy was described for highly selected patients whose biopsies were inconclusive, at the authors' institution (Hyogo College of Medicine, Japan). No patient count was given; one representative case was illustrated.
• Main results:
  • In the authors' proposed approach, when only nonspecific inflammation is seen at thoracoscopy, a 2 by 1 cm whole-layer piece of parietal pleura is taken from 3 different sites. The authors limit biopsy to 3 sites to avoid reducing the chance of cure.
  • In the representative case, the three VATS biopsy specimens showed atypical mesothelial cells with limited invasion into submesothelial fibrous tissue, but no invasion into subpleural fat.
  • In the same case, diagnostic total parietal pleurectomy found several small nodules with a maximum size of 1 to 2 mm. Atypical mesothelial cells invaded subpleural fat, and the case was diagnosed as epithelioid type malignant pleural mesothelioma.
  • The authors argued that the operation may carry less risk than pleurectomy/decortication because it skips removal of the visceral pleura. They also argued it is both a diagnostic and a therapeutic procedure.
• The authors' conclusion: The authors concluded that considering diagnostic total parietal pleurectomy in patients with strong clinical suspicion but no definitive pathological diagnosis after full investigation, including thoracoscopic biopsies, may lead to improved survival in malignant pleural mesothelioma.
• Limitations the authors state:
  • The authors stated that there is currently no proof that early discovery of mesothelioma cures patients or improves their survival.
  • The authors acknowledged that performing pleurectomy without a definitive pathological diagnosis is open to debate. They said it carries a considerable ethical barrier and should be done as a clinical trial.

Topics

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

Medical terms in this study, explained in our Lexicon: Pleural Mesothelioma, Prognosis, Pleural Effusion, Cytology, Pleural Biopsy, Informed Consent.

Related studies

• Circulating endothelial cell (CEC) as a diagnostic and prognostic marker in malignant pleural mesothelioma (MPM) — K. Yoneda, F. Tanaka, et al. (2012)
• Pathological and molecular biological approaches to early mesothelioma — T. Tsujimura, I. Torii, et al. (2012)
• Clinical Outcomes With Recurrence After Pleurectomy/Decortication for Malignant Pleural Mesothelioma — A. Nakamura, T. Takuwa, et al. (2020)
• Circulating tumor cells (CTCs) in malignant pleural mesothelioma (MPM) — K. Yoneda, F. Tanaka, et al. (2014)
• Lung-sparing total pleurectomy: the surgical option of choice in malignant pleural mesothelioma? — D.A. Waller (2013)
• Well-differentiated papillary mesothelioma with invasion to the chest wall — I. Torii, M. Hashimoto, et al. (2010)

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