Peripheral biphasic adenocarcinoma of the lung: light microscopic and immunohistochemical findings

Our plain-English summary of Peripheral biphasic adenocarcinoma of the lung: light microscopic and immunohistochemical findings, by P.T. Cagle, L.C. Alpert, P.A. Carmona (Human Pathology, 1992).

The study

• Authors: P.T. Cagle, L.C. Alpert, P.A. Carmona
• Journal: Human Pathology
• Published: 1992;23(2):197-200
• Type of article: Case report
• Cited by: 10 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

We report two cases of peripheral biphasic adenocarcinoma primary in the lung. To our knowledge, peripheral adenocarcinoma of the lung with a spindle-cell component has not been described previously. Diffuse positive cytokeratin and negative vimentin immunostaining of the spindle-cell components support an epithelial differentiation of the malignant spindle cells. Although study of additional cases is needed, our initial findings suggest that immunohistochemical staining pattern may help distinguish these neoplasms from other biphasic neoplasms primary or secondary to the lung, such as carcinosarcoma or malignant mesothelioma.

In plain English

This article reported two cases of a lung cancer the authors called peripheral biphasic adenocarcinoma: an adenocarcinoma in the outer lung that also contained malignant spindle-shaped cells. The authors stated that, to their knowledge, this was the first report of such tumors. Both patients, a man and a woman, had smoking histories and coin lesions on chest x-ray. Lymph nodes removed at surgery were negative for cancer. The article did not discuss asbestos exposure. In both tumors, the gland-forming and spindle-cell parts stained strongly for cytokeratin and EMA and were negative for vimentin and several other markers. The first tumor was also CEA positive and the second was mucin positive. The authors concluded that this pattern supports an epithelial (carcinoma) nature of the spindle cells, and that such stains may help tell these tumors apart from biphasic mesothelioma. They noted that this distinction may matter for medicolegal reasons if such a tumor spreads along the pleura. They also noted that only two cases were examined and that not all adenocarcinomas are positive for these markers.

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), with light microscopy and immunohistochemistry
• Who was studied: Two patients. Case 1 was a man with a smoking history, a right lower lobe coin lesion, and a right pneumonectomy at Jess Parrish Memorial Hospital. Case 2 was a woman with a heavy smoking history (OCR suggests 80 to 100 pack-years), cough, slight dyspnea and weight loss, a right upper lobe coin lesion, and a right upper lobectomy at The Methodist Hospital. Patients' ages are unreadable in the text.
• Exposure: No asbestos or occupational exposure was reported. The only exposure mentioned was cigarette smoking in both patients.
• Main results:
  • Case 1: a moderately well-differentiated adenocarcinoma, predominantly acinar, with a bronchioloalveolar pattern at the margins, surrounded by a stroma of malignant spindle cells. Both the epithelial and spindle-cell components were strongly positive for cytokeratin, EMA and CEA and negative for vimentin, B72.3, Leu-M1, muscle-specific actin, S-100 and desmin.
  • Case 2: two lesions in the right lung apex, a 2-cm bronchioloalveolar carcinoma and a 1.5-cm subpleural adenocarcinoma with mucicarmine-positive glands and a sarcomatoid spindle-cell stroma. Both components were strongly positive for cytokeratin and EMA and negative for CEA, vimentin, B72.3, Leu-M1, muscle-specific actin, S-100 and desmin.
  • Case 1 had no squamous cell differentiation. Case 2 had a small focus of squamous cell cancer on a separate section, and serial sectioning showed no junction between it and the spindle-cell component.
  • Lymph nodes were negative for metastatic carcinoma in both cases (hilar and lobar in case 1, lobar in case 2).
• The authors' conclusion: The authors concluded that the cytokeratin-positive, vimentin-negative spindle cells support epithelial differentiation. They concluded that immunohistochemical and histochemical findings may help differentiate biphasic adenocarcinomas from biphasic mesotheliomas when routine microscopy is unclear. In their view, the CEA positivity in case 1 and the mucin positivity in case 2 supported adenocarcinoma over mesothelioma. They noted that the distinction may be needed for medicolegal reasons if such a tumor spreads along the pleura.
• Limitations the authors state:
  • Only two cases were examined.
  • More cases are needed to determine whether this staining pattern is consistently seen in biphasic adenocarcinomas.
  • Not all adenocarcinomas are positive for mucin or immunohistochemical markers, so distinguishing them from mesothelioma may still be difficult.
  • Whether these tumors behave differently from other lung adenocarcinomas or carcinosarcoma, including in response to therapy, is unknown.

Topics

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

Medical terms in this study, explained in our Lexicon: Biphasic Mesothelioma, Adenocarcinoma, Spindle Cell, Immunohistochemistry, Neoplasm, Malignant Mesothelioma.

Related studies

• Calretinin, thrombomodulin, CEA, and CD15: a useful combination of immunohistochemical markers for differentiating pleural epithelial mesothelioma from peripheral pulmonary adenocarcinoma — C.E. Comin, L. Novelli, et al. (2001)
• Experimental lung tumors following specific intrabronchial application of chrysotile asbestos. Longitudinal light and electron microscopic investigations in rats — E. Fasske (1988)
• Immunohistochemical panels for differentiating epithelial malignant mesothelioma from lung adenocarcinoma: a study with logistic regression analysis — R. Carella, G. Deleonardi, et al. (2001)
• Immunohistochemical distinction of malignant mesothelioma from pulmonary adenocarcinoma with anti-surfactant apoprotein, anti-Lewisa, and anti-Tn antibodies — M. Noguchi, T. Nakajima, et al. (1989)
• Immunohistochemical reactivity in mesothelioma and adenocarcinoma: a stepwise logistic regression analysis — A. Dejmek, A. Hjerpe (1994)
• Adenocarcinoma simulating mesothelioma: a clinicopathologic and immunohistochemical study of 29 cases — M.N. Koss, M. Fleming, et al. (1998)

Browse more research in Human Pathology, or return to medical research.