Marwa Shoeb MBBS, Abstract Co-Author: Nothing to Disclose

Anouchka Goldman, Abstract Co-Author: Nothing to Disclose

Maria Joao Klusmann MD, Abstract Co-Author: Nothing to Disclose

Arjun Nair MBCHB, FRCR, Presenter: Nothing to Disclose

Visvalingam Gnanananthan, Abstract Co-Author: Nothing to Disclose

Ioannis Vlahos MBBS, Abstract Co-Author: Research grant, Bayer AG Consultant, Siemens AG Consultant, Bayer AG

Kirupa Haran Jogeesvaran FRCR, MRCP, Abstract Co-Author: Nothing to Disclose

TNM UICC7 upstages malignant effusions from T4 to M1a disease. The study aimed to determine: the incidence of pleural effusions in NSCLC patients, the rates of aspiration under the prior TNM staging (UICC6) and the impact of cytological results in staging under both editions.

A retrospective study of 200 consecutive NSCLC CT staging examinations originally managed under UICC6 was performed. Two pulmonary radiologists recorded all TNM descriptors and UICC6 and UICC7 staging. Pleural effusion incidence was recorded and any prior aspiration recorded. In aspirated cases the impact of cytology results under UICC6 and UICC7 was determined. In non-aspirated cases the impact of other disseminated disease was evaluated and the potential of a possible negative cytological aspiration determined.

51 of 200 patients (25.5%) had a CT evident pleural effusion, 31 of which were tapped (60.8%). Of these, 20 (64.5%) had positive cytology (80% ipsilateral, 20 bilateral). Under UICC6 positive cytology upstaged 5 patients to Stage IIIB and 15 patients to Stage IV; under UICC7 all of these are reclassified as Stage IV disease. There were 11 negative effusions (64% ipsilateral, 36% bilateral). In 7 of 11 (63.6%) negative aspirations, the result did not affect the staging under either classification. In the remaining 4 cases disease was downstaged to IB (3 cases) and IIA (1 case) under both UICC6 and UICC7. In the 20 non-aspirated effusions, 16 (80%) had other disease and negative cytology would not have altered the staging from IIIB/IV under UICC7. However, in 4 cases (20%), not aspirated due to small effusion size, the absence of other evidence of disseminated malignancy and negative cytology would have resulted in downstaging to stage IIIA in 3 cases and IIB in 1 case under UICC7.  

Pleural effusions occur in over a quarter of NSCLC patients. As the presence of positive cytology upstages patients to Stage IV disease there is now a greater need for aspiration as currently at least 35.5% of aspirated effusions are negative and in up to 15.7% of patients exclusion of a neoplastic effusion may result in operable low stage disease.

Benign pleural effusions are common in NSCLC; upstaging of malignant effusions in UICC7 suggests aspiration rates may need to increase to accurately define low stage cases with benign effusions.

Shoeb, M, Goldman, A, Klusmann, M, Nair, A, Gnanananthan, V, Vlahos, I, Jogeesvaran, K, Staging Significance of Effusions Identified at CT for Non-Small Cell Lung Cancer (NSCLC): Impact of the New TNM Classification (UICC7) on Aspiration Rates and Disease Stage.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9010610.html