Primary pulmonary rhabdomyosarcoma in a 5-month-old boy: a case report

Primary Pulmonary Alveolar Rhabdomyosarcoma in a Pediatric Patient: A Case Report With Literature Review

Rhabdomyosarcoma (RMS) is a rare soft tissue tumor originating from skeletal muscle that is mostly reported in children. The most common sites of involvement are the head, neck, and extremities. The 2020 WHO classification divide RMS into four types: embryonal, alveolar, pleomorphic, and spindle cell/sclerosing. Reports of RMS with primary lung origin are rare. We present a case of RMS in a 16-month-old boy who presented with a lung mass and microscopic examination with fluorescence in situ hybridization confirmed the diagnosis of alveolar RMS. In conclusion, RMS should be considered in the differential diagnosis of any lung mass with small round blue cell morphology in the microscopic evaluation and should be distinguished from metastatic RMS of other sites, pleuropulmonary blastoma, lymphoma, neuroblastoma, primitive neuroectodermal tumor (PNET)/EWING, and malignant peripheral nerve sheet tumors (MPNST).

Pediatric airway tumors: A report from the International Network of Pediatric Airway Teams (INPAT)

OBJECTIVE

Primary tracheobronchial tumors (PTTs) are rare heterogeneous lesions arising from any part of the tracheobronchial tree. Nonspecific symptoms may lead to delayed diagnosis that requires more aggressive surgical treatment. An analysis of cases collected by the International Network of Pediatric Airway Team was undertaken to ensure proper insight into the behavior and management of PTTs.

METHODS

Patients <18 years of age with a histological confirmation of PTT diagnosed from 2000 to 2015 were included in this multicenter international retrospective study. Medical records, treatment modalities, and outcomes were analyzed. The patient presentation, tumor management, and clinical course were compared between malignant and benign histotypes. Clinical and surgical variables that might influence event-free survival were considered.

RESULTS

Among the 78 children identified, PTTs were more likely to be malignant than benign; bronchial carcinoid tumor (n = 31; 40%) was the most common histological subtype, followed by inflammatory myofibroblastic tumor (n = 19; 25%) and mucoepidermoid carcinoma (n = 15; 19%). Regarding symptoms at presentation, wheezing (P = 0.001) and dyspnea (P = 0.03) were more often associated with benign growth, whereas hemoptysis was more frequently associated with malignancy (P = 0.042). Factors that significantly worsened event-free survival were age at diagnosis earlier than 112 months (P = 0.0035) and duration of symptoms lasting more than 2 months (P = 0.0029).

CONCLUSION

The results of this international study provide important information regarding the clinical presentation, diagnostic workup, and treatment of PTTs in children, casting new light on the biological behavior of PTTs to ensure appropriate treatments.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:E243-E251, 2020.

Primary pulmonary primitive neuroectodermal tumor (PNET): a clinicopathological and immunohistochemical study of six cases

BACKGROUND

The clinicopathological and immunohistochemical features of six primary pulmonary primitive neuroectodermal tumors (PNETs) are reported.

METHODS

The patients were four men and two women aged 22-56 years (mean = 32.3 years). The main presenting symptoms included chest pain, shortness of breath, and cough. The tumor size ranged from 4 to 9.6 cm.

RESULTS

Macroscopically, the tumors were circumscribed, yellow-white in color, and of soft and friable consistency. Histologically, the lesions were composed of a monomorphic population of solidly packed round cells with a round-to-ovoid nucleus, fine chromatin, small nucleoli, and scanty pale cytoplasm. Immunohistochemically, the tumor cells were uniformly positive for CD99, neuron-specific enolase, and vimentin, and single cases focally expressed cytokeratin and S100. Fluorescence in situ hybridization analysis performed in two cases showed positive rearrangement for the EWSR1 gene at the 22q12 locus. Follow-up information available for four patients showed that three had died 24-54 months after diagnosis and one patient is alive 11 months after diagnosis. Two patients were lost to follow-up.

CONCLUSION

Primary PNETs of the lung are rare tumors that need to be added to the differential diagnosis of primary pulmonary neoplasms composed of small cells. Awareness of this entity as a primary pulmonary neoplasm is required in order to avoid misdiagnosis and unsuitable treatment of patients.