case_images: PMC6875374_01
case_images: Ultrasound (US) of the left lower extremity: (a) Baker's cyst. (b) Follow-up US showing the increased size of baker's cyst. (c) Image depicting ruptured Baker's cyst.
case_images: CRIRH2019-1326734.001.jpg
case_images: PMC6875374_01_CRIRH2019-1326734.001.jpg
case_images: fig1
case_images: Ultrasound (US) of the left lower extremity demonstrated a Baker's cyst measuring 3.7 x 0.9 x 1.1 cm (Figure 1(a)) which increased to 8.0 x 6.5 x 2.3 cm (Figure 1(b)) on repeat US four days later. Follow-up US after two weeks revealed cyst rupture with hematoma (Figure 1(c)).
case_images: X-ray of the left elbow joint and bilateral knee joints. (a) Moderate osteophytosis at the humeroulnar articulation and involving the radial head with mild joint space narrowing and no joint effusion. (b) Anterior-posterior weight-bearing view; no acute fracture/dislocation, and joint spaces grossly preserved.
case_images: CRIRH2019-1326734.002.jpg
case_images: PMC6875374_01_CRIRH2019-1326734.002.jpg
case_images: fig2
case_images: X-rays revealed unremarkable left knee joint and findings consistent with osteoarthritis of the left elbow (Figure 2).
case_images: Computed tomography (CT) scan of the chest with contrast before and after nivolumab. (a) CT chest before initiation of nivolumab; an axial image depicting significant mediastinal and right hilar lymphadenopathy. (b) CT chest after 12 cycles of nivolumab; no hilar or mediastinal lymphadenopathy identified.
case_images: CRIRH2019-1326734.003.jpg
case_images: PMC6875374_01_CRIRH2019-1326734.003.jpg
case_images: fig3
case_images: Although the patient's tumor responded to nivolumab (Figure 3), it was stopped after 12 cycles due to MSK irAE.
case_images: Flowchart illustrating the complete clinical course of the patient. ANA: antinuclear antibody, US: ultrasound, MTX: methotrexate, HCQ: hydroxychloroquine, DMARDs: disease-modifying antirheumatic drugs.
case_images: CRIRH2019-1326734.004.jpg
case_images: PMC6875374_01_CRIRH2019-1326734.004.jpg
case_images: fig4
case_images: Unfortunately, the patient had severe inflammatory arthritis which worsened the quality of life due to nivolumab; the shared decision was made not to reintroduce nivolumab (Figure 4).