چکیده (انگلیسی):

Introduction: An extremely rare case of mixed squamous cell and glandular papilloma of the lung is
reported. The correlation between the radiological and the pathological features as well as the clinical
pitfall in making a diagnosis is discussed.
Presentation of case: An asymptomatic 68-year-old female with a cigarette smoking habit presented with
a small nodule in her peripheral lung. A wedge resection was performed though it failed on-site diagnosis
which was instead obtained following pathological scrutiny. The postsurgical course was excellent
with no recurrence of disease.
Discussion: A small ground glass nodule gradually enlarged and transformed to a partially solid nodule a
year and a half later. This transformation falsely made us suspect an early adenocarcinoma development.
Eventually, the extremely rare subtype of pulmonary papilloma, with biphasic glandular and squamous
cells, had been demonstrated to obstruct the peripheral bronchiole; and the adjoining alveoli had filled
with a large volume of mucus. These pathological features seemed to have constituted the inner solid
portion and the marginal ground glass portion respectively in the CT images, mimicking invasive lepidic
adenocarcinoma.
Conclusion: Both pre- and intra-operative diagnoses are difficult mainly because of the rareness of the
disease, however, mixed squamous cell and glandular papilloma may be considered in case the presence
of primary adenocarcinoma is not validated.