Case Report Invasive Mucinous Adenocarcinoma of the Lung ç— ä¾‹ ...

H. T. Liu et al./JCRP 28(2012) 94-98 95
tinued [1]. Unlike adenocarcinoma in situ (AIS) and
minimally invasive adenocarcinoma (MIA), which
both have nearly 100% 5-year survival rates, invasive
mucinous adenocarcinoma (formerly mucinous BAC)
has a comparatively poorer prognosis. Within the criteria
for the new staging system, there is no collected
survival data that has been fully presented for mucinous
adenocarcinoma of the lung. However, prior literature
shows that the disease has unusual clinical
presentation and distinct immunohistochemical features.
CASE REPORT
A 50-year-old woman was transferred to our hospital.
One month before admission, she had increasing
shortness of breath and progressive facial swelling.
She visited a local hospital for medical assistance,
where a subsequent chest X-ray showed massive right
pleural effusion and widening of the upper mediastinum.
Thoracentesis yielded bloody exudative effusion,
and a pig-tail tube was inserted for drainage. The
drainage volume was 400-500 ml per day. Subsequently,
the pig-tail tube was then replaced by a chest
tube due to blood clot occlusion. Cytological examination
indicated adenocarcinoma. The patient’s chest
CT scan depicted massive right pleural effusion, a
thrombus at the superior vena cava, and a 3 x 3 cm
mass at the anterior mediastinum. The thrombus was
thought to be tumor-related. CT-guided biopsy of the
anterior mediastinum mass revealed metastatic adenocarcinoma
with immunohistochemical stain as CK7
(-), TTF-1 (-), CK20 (+) and CDX2 (+), suggesting
metastatic adenocarcinoma of the lower gastrointestinal
tract. The patient underwent esophagogastroduo-
*Corresponding author: Yuh-Min Chen, M.D., Ph.D.
* 通 訊 作 者 : 陳 育 民 醫 師
Tel: +886-2-28757563
Fax: +886-2-28763466
E-mail: ymchen@vghtpe.gov.tw
Figure 1. Mucinous pools contain poorly differentiated
adenocarcinoma cells (200X)
denoscopy (EGD endoscopy) and colonoscopy, with
resulting negative findings. PET/CT scan revealed uptake
in the patient’s anterior mediastinum and the right
lower lung, and she was then treated as metastatic adenocarcinoma
of lower gastrointestinal origin. After this
diagnosis, the patient came to our hospital for a second
opinion, where additional diagnostic tests were performed.
Similar to her previous results, the patient’s
brain MRI and mammography were negative; gynecological
ultrasound exam revealed myomas only. We
repeated the chest CT scan and performed biopsy to the
pleural lesions. The pathology report showed metastatic
adenocarcinoma with immunohistochemistry noted as
CK7 (+), CK20 (+), CDX2 (+), TTF-1 (-), CK5/6 (-),
and P63 (-) (Figures 1, 2). EGFR sequencing reported
no mutation. Because of the discordance of immunochemistry
profiles between the pleural sample and the
anterior mediastinal tumor, we discussed this case in
our lung cancer multidisciplinary conference. The
members concluded that the tumor was compatible with
invasive mucinous adenocarcinoma of lung, and we
treated the patient with paclitaxel plus cisplatin. Three
days later, her pleural effusion markedly decreased, and
chest film indicated widening of the anterior mediastinum.
We maintained this regimen for 2 months, but
unfortunately her disease progressed (Figure 3).