Clinical relevance of human mammaglobin mRNA in pleural effusion from patients undergoing thoracoscopy: a pilot study.
BACKGROUND
human mammaglobin (hMAM) expression has been reported in pleural effusions (PE). The aim of this study was to assess the clinical relevance of hMAM mRNA in PE from patients who underwent thoracoscopy.


METHODS
A total of 288 patients with PE were studied, 155 of which were diagnosed with malignant and 133 with non-malignant diseases by thoracoscopy. Cells from PE were analyzed by nested hMAM RT-PCR. Statistical analyses were performed to evaluate the diagnostic performance parameters (DPP), the association between hMAM expression and benign or malignant status and the relative risk of cancer for patients with negative thoracoscopy showing hMAM positivity.


RESULTS
hMAM mRNA was found in 68/288 (23.6%) PE samples of which 51 were from the 155 patients diagnosed with malignant diseases and 17 were from the 133 patients diagnosed with non-malignant diseases. A significant correlation between hMAM expression and malignancy was found (OR=3.04) and the DPP were as follows: sensitivity=32.9%, specificity=87.2%, accuracy=58.0%, positive predictive value=75.0% and negative predictive value=52.7%. Among the patients with negative thoracoscopy (n=133), 5/17 (29.4%) hMAM-positive patients had or developed a tumor during the 18-month follow up period, as compared to 10/116 (8.6%) hMAM-negative patients (relative risk of 4.6 for developing a malignancy).


CONCLUSIONS
These findings suggest a possible application of hMAM RT-PCR detection in PE as to identify a false-negative thoracoscopy in non-specific pleuritis.
Division of Pneumology, San Bartolomeo Hospital, Sarzana (La Spezia) - Italy.
Pier Aldo
PA
Canessa
Carmen
C
Manta
Paola
P
Ferro
Maria Cristiana
MC
Franceschini
Massimiliano
M
Sivori
Vincenzo
V
Fontana
Franco
F
Fedeli
Maria Pia
MP
Pistillo
Silvio
S
Roncella
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D060785:Mammaglobin A / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics*; D008875:Middle Aged; D010865:Pilot Projects; D016066:Pleural Effusion, Malignant / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology / Q000601:surgery*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D060785:Mammaglobin A; D012333:RNA, Messenger