Results:
Patient 1 is a 23-month old toddler who presented with lower
back pain, gradually worsening ataxia and leg weakness over the previous
5 days. Physical examination was initially non-suggestive, but quickly
progressed to lower limb weakness and frank paraplegia. His blood
investigation were normal and chest X-Ray was suggestive of a soft
tissue paravertebral mass at the level of upper thoracic vertebrae. This
was followed by MRI scan that demonstrated a paravertebral mass at the
level of T2-T4 vertebrae, causing spinal cord compression and edema. He
underwent emergency laminotomy and laminoplasty by the neurosurgeons and
a de-bulking procedure, which relieved pressure on the spinal cord
resulting in return of lower limb function over the next 48 hours. His
urinary Vanillylmandellic Acid (VMA)/creatinine ratio and Homovanillic
Acid (HVA)/creatinine ratio were mildly elevated. Histopathology of the
resected tissue showed poorly differentiated Neuroblastoma. Tumor
cytogenetics did not reveal any high-risk features.
On 68Ga-DOTATATE PET/CT scan, increased DOTATATE
uptake was seen in the left paravertebral mass extending into the
posterior mediastinum and posterior chest wall and crossing the midline.
Another focus of increased DOTATATE uptake was noted along the right
paravertebral aspect of thoracic vertebrae at the level of T2 and T3.
Additionally, a calcified distinct posterior mediastinal node with
increased DOTATATE uptake was also noted. These findings are summarized
in Table 1 and 68Ga-DOTATATE imaging is shown in (Fig
1).
Patient 2 is a six-year old girl who presented with a mild
intermittent limp over the previous 2 months. She did not have any other
symptoms. On physical examination, she was unable to stand straight due
to left leg pain and had a mildly tender left side of lower abdomen.
X-Ray of her pelvis demonstrated 2 radiolucent lesions in her left
femur. Further imaging studies including MRI scan of her abdomen and
pelvis demonstrated a large left supra-renal mass and numerous bony
metastatic lesions in addition to several enlarged retroperitoneal lymph
nodes. Her urinary VMA/Creatinine ratio and HVA/Creatinine ratio were
moderately elevated. A core biopsy from the suprarenal mass was carried
out under ultrasound guidance. Histopathology of the mass confirmed the
diagnosis of poorly differentiated Neuroblastoma, which did not have any
high-risk cytogenetic features. Her bone marrow was infiltrated by
Neuroblastoma.
On 68Ga-DOTATATE PET/CT scan, intense DOTATATE uptake
was noted in the large left suprarenal mass with areas of photopenia
corresponding to necrosis and calcifications. Uptake was also noted in
the right adrenal bed as well as in the right retrocrural region. A few
bony skull lesions with increased uptake were noted including the skull
base most consistent with disease involvement. Extensive skeletal
metastasis along the axial and appendicular skeleton were noted with
evidence of bone marrow infiltration. These findings are summarized in
Table 1 and 68Ga-DOTATATE imaging is shown in (Fig 2).
Patient 3 is a 3.5-year old girl who presented with weight
loss, left eye swelling, body aches and constitutional symptoms over
several months. She was cachectic, severely malnourished and had left
sided proptosis. MRI scan showed a right upper abdominal mass arising
from the adrenal gland. She also had numerous liver metastases, enlarged
lymph nodes along the lower pole of the left kidney and multiple
vertebral lesions. It also showed enlarged mediastinal lymph nodes at
the level of tracheal bifurcation and left posterior mediastinum. Her
bone marrow was infiltrated by malignant cells. Urinary VMA/Creatinine
ratio and HVA/Creatinine ratio were grossly elevated. In the presence of
elevated catecholamines and highly suggestive bone marrow results, we
elected not to carry out tumor biopsy.
68Ga-DOTATATE PET/CT scan demonstrated intense
heterogeneous uptake in the right adrenal mass with skeletal metastatic
deposits and diffuse bone marrow infiltration. It also demonstrated
uptake in the thoracic and abdominal lymph nodes seen on MRI scan.
Additionally, there were two bony lesions in the skull vault. These
findings are summarized in Table 1 and selected representative images on68Ga-DOTATATE imaging are shown in (Fig 3).