Abstract YO24
Case summary
A 59-year-old Thai female, with a history of smoking 13 pack-year. Her underlying diseases are HT, DLP, CKD , OA knee, and migraine. She had history of treated pulmonary tuberculosis 30 years ago. She had no family history of cancer
She presented to the emergency department with progressive proximal weakness in both legs over 2 weeks. Her symptoms worsened gradually to the point where she could only walk with assistance, no any weakness in both arms, no facial palsy or drooping eyelids, no numbness was experienced.
She denied any history of fever. Her weight had been lost 8 kg. She reported no cough, dyspnea, joint pain, rash.
Upon initial assessment in the ER, vital signs were normal. Physical examination revealed proximal leg motor power grade 3 bilaterally, sensation and cranial nerves are all intact. Deep tendon reflexes are normal.
The laboratory results showed normal values for CBC, BUN, Creatinine, Electrolyte
The abnormal laboratory results are as follows
| CPK | 10,716 U/L |
|---|---|
| ANA | 1:80 |
| Anti-SRP | 2+ |
| Anti-HMGCR | 1+ |
| AST | 447 U/L |
| ALT | 257 U/L |
An expert rheumatology consultation was initiated to help with the differential diagnosis. The team suspects Inclusion Body Myositis (INMN) due to quick onset and progression of symptoms, the positive myositis antibody SRP, and patient's history of prior statin use.
Patient then received IVMP for 3 days. Afterward, weakness in both legs improved to motor power grade 4 and steroid was gradually tapered.
Further investigation of IMNM has been conducted. HRCT results revealed a conglomerate enlarged lymph node in the subcarinal region measuring 3.6 cm, with no definite lung masses.
A pulmonologist was consulted for a transbronchial biopsy of a mediastinal lymph node. The pathology results showed neoplastic cells, favoring small cell carcinoma. The tissue specimen was stained with CD56, chromogranin A, synaptophysin, and Ki-67 95%. Further CT chest&whole abdomen shows no abnormalities in other organs.
The final diagnosis is Limited stage small cell lung cancer, and the treatment plan includes Platinum-etoposide chemotherapy along with CCRT