Figure 1: a) initial outpatient CT scan of the chest
highlighting the lung mass; b) gross specimen of the lung mass; c)
histological image showing spindle cell proliferation with prominent
inflammatory infiltrate encroaching on adjacent alveoli; d) histological
image highlighting the mixed inflammatory cells including plasma cells,
lymphocytes, and eosinophils.
The patient was referred to pediatric surgery and pediatric oncology and
she was reviewed at tumor board. A video assisted thoracoscopy (VATS)
with left lower lobe lobectomy was performed three months after the
initial hospitalization. The left lower lobe (inclusive of the tumor)
and associated axillary nodes were removed en bloc in a via thoracotomy.
The tumor was sent to pathology without fixation. Postoperatively the
patient recovered quickly, with removal of her chest tube and discharge
home on the first postoperative day. A post-op chest x-ray demonstrated
pneumothorax. She underwent chest tube placement four weeks after her
initial operation due to worsening of pneumothorax following discharge
from the hospital and had complete, persistent resolution of the
pneumothorax.
Pathological examination showed a spindle cell lesion with associated
lymphoplasmacytic and histiocytic inflammation. The final pathologic
diagnosis made by an outside facility was an inflammatory
myofibroblastic tumor (IMT)/inflammatory pseudotumor with
microscopically negative margins and negative lymph nodes. The patient
still has residual visual abnormalities in the left eye and regularly
has imaging to monitor tumor recurrence in the chest and abdomen.
Neuromyelitis optic spectrum disorders and IMT are uncommon conditions,
afflicting both adults and children. NMOSD is an CNS autoimmune disorder
in which antibodies to the aquaporin-4 water channel are identified in
one-half to two-thirds of children1. IMT are usually
benign pulmonary and abdominal neoplasms that most commonly affect
children and young adults. While the exact tumor pathogenesis remains
uncertain, an overlap exists between IMTs and IgG-4 related disorders.
NMOSD is known to be associated with other autoimmune disorders such as
systemic lupus erythematosus, Sjogren syndrome, autoimmune thyroid
disease, and myasthenia gravis4. However, no link
between NMO and IMTs has been identified.
NMOSD often presents with visual deficits, sensory dysfunction and
constitutional symptoms like fever, nausea, vomiting, and seizures. In
the pediatric population, approximately 30-50% of patients experience
optic neuritis during their first NMOSD episode. While NMOSD typically
targets the CNS, cases of NMO with inflammatory pulmonary manifestations
have been reported2. IMT symptoms are nonspecific,
varying with location, such as cough and chest pain for pulmonary IMTs
and gastrointestinal symptoms for abdominal IMTs5. In
this patient’s case, symptoms primarily aligned with NMOSD, with finger
clubbing being the sole pulmonary symptom. Given the correlation between
NMOSD and other autoimmune inflammatory disorders, it’s imperative to
consider autoimmune or inflammatory pathologies during initial NMOSD
diagnosis, particularly in younger patients.
NMOSD is a highly relapsing disorder and therefore long-term
immunotherapy is required with rituximab, mycophenolate mofetil, and
azathioprine being the most commonly used long term therapies in
children. Acute episodes are treated with high dose prednisolone,
plasmapheresis, or IVIG1. IMTs are typically managed
through complete mass resection with negative margins.
In conclusion, IMT of the lung and neuromyelitis optica spectrum
disorders (NMOSD) are both rare inflammatory conditions with low
incidence rates. This is the first reported case with pulmonary IMT
along with NMOSD.