Detection of lymph node metastases in pediatric and adolescent/young adult sarcoma: Sentinel lymph node biopsy versus fludeoxyglucose positron emission tomography imaging-A prospective trial.

BACKGROUND: Lymph node metastases are an important cause of treatment failure for pediatric and adolescent/young adult (AYA) sarcoma patients. Nodal sampling is recommended for certain sarcoma subtypes that have a predilection for lymphatic spread. Sentinel lymph node biopsy (SLNB) may improve the diagnostic yield of nodal sampling, particularly when single-photon emission computed tomography/computed tomography (SPECT-CT) is used to facilitate anatomic localization. Functional imaging with positron emission tomography/computed tomography (PET-CT) is increasingly used for sarcoma staging and is a less invasive alternative to SLNB. To assess the utility of these 2 staging methods, this study prospectively compared SLNB plus SPECT-CT with PET-CT for the identification of nodal metastases in pediatric and AYA patients. METHODS: Twenty-eight pediatric and AYA sarcoma patients underwent SLNB with SPECT-CT. The histological findings of the excised lymph nodes were then correlated with preoperative PET-CT imaging. RESULTS: A median of 2.4 sentinel nodes were sampled per patient. No wound infections or chronic lymphedema occurred. SLNB identified tumors in 7 of the 28 patients (25%), including 3 patients who had normal PET-CT imaging of the nodal basin. In contrast, PET-CT demonstrated hypermetabolic regional nodes in 14 patients, and this resulted in a positive predictive value of only 29%. The sensitivity and specificity of PET-CT for detecting histologically confirmed nodal metastases were only 57% and 52%, respectively. CONCLUSIONS: SLNB can safely guide the rational selection of nodes for biopsy in pediatric and AYA sarcoma patients and can identify therapy-changing nodal disease not appreciated with PET-CT. Cancer 2017;155-160. © 2016 American Cancer Society.

Calcifying nested stromal-epithelial tumor (CNSET) of the liver: a newly recognized entity to be considered in the radiologist's differential diagnosis.

Calcifying nested stromal-epithelial tumor (CNSET), an extremely rare tumor found in the liver, was first described in 2001 by Ishak et al. The characteristic imaging features include large size, well-circumscribed, enhancing mass with calcification. To our knowledge, since 2001, there have been 29 reported. Typically arising from the right hepatic lobe, it is primarily found in children and shows clear predilection for females. Emphasizing imaging, we report a 14-year-old female with Beckwith-Wiedemann syndrome who presented with CNSET.

Virilizing ovarian dermoid cyst with leydig cells.

BACKGROUND: The clinical observation of virilization is a rare finding that has a number of possible explanations. Overall, ovarian tumors causing virilization are exceedingly rare and mostly occur in post-menopausal women. In fact, there are no reported cases of virilization from a testosterone-producing ovarian dermoid in the adolescent female age group. The most frequent germ cell tumor derived from the ovaries is the benign cystic teratoma (dermoid) which accounts for 25% of all ovarian neoplasms. Teratomas consist of tissues that recapitulate the ectoderm, endoderm, and mesoderm. Usually the tumors are asymptomatic, but they occasionally can cause severe pain if there is torsion or if sebaceous material perforates the cyst wall, leading to reactive peritonitis. CASE: A 12-year-old female was found to have a large 3 5 x 19 x 12 cm ovarian mature cystic teratoma arising from her right ovary. The patient also displayed evidence of masculinization demonstrated by a deepening voice and clitoromegaly. The dermoid was producing large amounts of testosterone from a nest of Leydig cells found pathologically in the mass. CONCLUSION: Benign cystic teratomas can produce active hormones, albeit rarely. This is a finding important to consider when ovarian cystectomy is performed for removal of a benign cystic teratoma.