The Korean Journal of Internal Medicine Vol. 29, No. 5 (Suppl. 1)
WCIM 2014 SEOUL KOREA 365
Poster Session
PS 1433 Hemato-Oncology (Oncology) Systemic Nocardiosis Mimicking Disease Flare-Up Af- ter Discontinuation of Gefi tinib in a Patient with EG- FR-Mutant Lung Cancer
Mihong CHOI1, Youngjoo LEE1, Sang Hyun HWANG2, Jin Soo LEE1 National Cancer Center, Korea1, National Cancer Center, Korea2
Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) tend to be dramatically effective in patients with non-small cell lung cancer (NSCLC) harboring sensitizing EGFR mutations. However, most of the patients with EGFR-mutant lung cancer who have initially shown response to EGFR-TKI eventually acquire resistance to the drug. Moreover, a few of them experience accelerated progression of disease on discontinuation of EGFR-TKI. Thus, even after radiologic progression, maintenance of EGFR-TKI until administration of another effective treatment is recommended in this patient group. A 56-year-old man with recurrent EGFR-mutant lung cancer metastatic to the brain was treated with fi fteen cycles of gefi tinib, until when progression in the lung was demonstrated on restaging CT scan. While he was on the eleventh cycle of gefi tinib, the patient underwent stereotactic radiosurgery (SRS) for his brain lesion causing right hemiparesis, but grew dependent on corticosteroid afterwards due to de- velopment of cerebral necrosis with recurrent right-sided weakness. As his lung lesions more than doubled over two weeks after discontinuation of the EGFR-TKI, however, gefi tinib was resumed under the impression of fl are-up of the gefi tinib-sensitive lung cancer. Three weeks later, the EGFR-TKI retrial proved ineffective, both from clinical fi ndings and from multiple new lesions in the lung and brain on restaging imaging.
Subsequent brain biopsy revealed abscess material, and a sputum culture grew Nocar- dia species, making a fi nal diagnosis of systemic nocardiosis, rather than cancer fl are- up. Both fl are-up of EGFR-mutant lung cancer and disseminated infection of any sorts can lead to rapid clinical deterioration, but can overlap in their clinical presentation.
High index of suspicion, therefore, is required to differentiate between them, and confi rmative evaluation such as percutaneous biopsy might be of help to guide further therapeutic management in appropriate clinical setting.
PS 1434 Hemato-Oncology (Oncology) Metastatic Mandibular Tumor Presenting as a Facial Swelling: An Initial Manifestation of Lung Adenocarci- noma
Hye Jeong Cho1, Hee Jin Hong1, So Dam Hong1, Jae Kyoung Shin1, Bo Hye Kim1, So Young Chong1, Doyoun Oh1, Jisu Oh1
Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Korea1
Metastatic lesions to the oral region are uncommon and account for 1% of all malig- nancies of the jaw. The current study describes a rare case of a 74-year-old woman who presented with a painful swelling of right facial area. She was a non-smoker and the family history was unremarkable. Computed tomography (CT) and magnetic reso- nance imaging (MRI) of neck showed about 5.5*5cm sized mass in the right mandible condyle and ramus with total destuction of condyle and invasion into right masseter and lateral pterygoid muscle. It looked like osteosarcoma. Sono-guided biopsy of the mass was performed. The results of the tissue indicated well-differentiated adenocar- cinoma. Immunohistochemical (IHC) analysis showed positive for cytokeratin 7, thyroid transforming factor 1 but negative for cytokeratin 20, vimentin. A contrast enhanced chest CT, which was performed to detect the primary cancer, revealed about 4.2cm sized mass in left upper lobe lingular segment and left lower lobe anterobasal seg- ment. The results of IHC stain and images favored metastatic adenocarcinoma from the lung. Moreover, activating mutation of epidermal growth factor receptor (EGFR) was detected (c.2573T>G (p.L858R) in exon 21). Subsequent PET-CT also confi rmed other metastatic disease in left humeral head and neck, right level II cervical lymph nodes, and right lower paratracheal lymph node. This case indicates that possible met- astatic disease should be suspected in patients presenting with a mandibular mass or swelling although metastatic mandibular tumor is even rare. Because their diagnosis may be the fi rst indication of an undiscovered malignancy at a distant primary site, the clinicians need to pay attention to this point, and evaluate patients who present unusual clinical symptoms thoroughly.
