Pleuropulmonary blastoma in an adolescent

The case

A previously healthy 16-year-old female patient presented to our facility with intermittent pleuritic chest pain and shortness of breath. Her symptoms started 2 days earlier with chest pain. The pain got worse with movement and breathing. She was not coughing, but did have shortness of breath that started with chest pain. Systems rating was negative for fever, chills, night sweats, and weight loss. There was no recent trauma, other than hitting her chest against a door after “passing out” the night before her pain developed. She had no known history of smoking, but said she vaped “a lot” in the past, but “stopped” 3 weeks before the pain started. The patient had no history of drug use. Medical history included post-traumatic stress disorder, asthma, bipolar disorder, and multiple personality disorder. Her medications include lithium, 300 mg twice daily; prazosin, 1 mg per day; and albuterol metered dose inhaler, 2 puffs, as needed. The patient had no personal or family history of cancer.

In the emergency department, her temperature was 36.7°C; heart rate was 90 beats per minute (min); respiratory rate, 18 breaths/min; and blood pressure, 112/81, mm Hg. Her height was 59 inches and weight, 48 kg (body mass index, 21). Her physical examination revealed a heart rate and rhythm within normal limits and normal breathing effort, but the patient had reduced breath sounds on the left side and mild tenderness to palpation on the left sternal margin. The rest of the exam was unremarkable. There was no pallor, hepatomegaly, splenomegaly, or adenopathy.

Laboratory evaluation included complete blood cell counts with differential, D-dimer and basal metabolic panel, all of which were within normal limits. The serum lithium level was subtherapeutic at 0.3 mg/dL. A urine drug screening was not obtained. A chest X-ray revealed a moderate to large left apical pneumothorax, an unremarkable cardiomediastinal silhouette, and no consolidation or effusion.

She was placed on a 2 L nasal cannula, with an oxygen saturation of 99%. No change in oxygen saturation was observed upon removal of the cannula. The thoracic surgery department was consulted; nonoperative treatment of her left-sided pneumothorax was initiated with oxygen via a nasal cannula.

Two days after admission, the patient developed worsening pain and shortness of breath. A repeated X-ray showed that the size of the pneumothorax had increased (Figure). Despite a chest tube placement with a pigtail catheter, the pneumothorax persisted and she required video-assisted thoracoscopic surgery (VATS) with left apical blebectomy, mechanical pleurodesis, and double placement of the left chest tube. The postoperative course was uncomplicated. The patient was discharged home on postoperative day 2 after chest tube removal. Gabapentin was added for pain relief at discharge. The resected lung tissue sample was sent for pathological examination.

Differential diagnosis

The most common cause of spontaneous pneumothorax in adolescents is secondary to an alveoli, but the differential diagnosis for pneumothorax is wide. The table lists primary and secondary causes of pneumothorax.1-3 Our patient had 3 risk factors for developing pneumothorax: blunt trauma from her syncope episode, vaping history, and asthma. When her pneumothorax did not resolve with pigtail catheter chest tubing placement, the VATS procedure allowed visualization and removal of a left apical bleb. Pathological results of the removed bleb revealed pleuropulmonary blastoma (PPB), type 1.

Discussion

Pulmonary neoplasms are rare primary tumors and rare causes of pneumothorax in children and adolescents. PPB, a rare childhood malignant intrathoracic tumor, is most commonly diagnosed in children under 6 years of age. It originates from the lungs or pleura and is classified into 3 subtypes: Type I (our patient), a pure lung cystic neoplasm with some malignant changes, usually occurs in infants and has a good prognosis; type II has both solid and cystic components, with a median age of diagnosis of 34 months; and type III, a solid neoplasm, has a median age of diagnosis of 44 months.4 In general, PPB has a poor prognosis due to its aggressive natural course, rare nature, and high misdiagnosis rate.5

The presentation of PPB often consists of vague symptoms, including respiratory distress, pneumothorax, shortness of breath, fever, and chest pain. Early manifestations include respiratory distress due to pneumothorax in type I or dyspnoea, fever and chest pain in types II and III.6 PPB has been identified in adults with a smoking history with a large breast mass, fever, chest pain and hemoptysis. 7 Our patient was older than the typical age of diagnosis for PPB, especially for type I neoplasm.

Type I tumors require surgical resection to diagnose and treat PPB. Type II and III lesions are treated with surgical resection, chemotherapy and/or radiation therapy when possible.5 The 5-year disease-free survival is 80% to 91% in patients with type I and less than 50% in patients with type I II and III.6

patient outcome

This patient was diagnosed with PPB after a spontaneous pneumothorax. She has no previous diagnosis of cancer or any other tumor. The diagnosis was made only after pathological examination of the resected lung tissue sample. She underwent surgical resection/lobectomy of the affected area in January 2020 and was referred to pediatric oncology, but there is no record of a visit. Due to multiple interstate movements, patient follow-up was inconsistent. By the last report, she had undergone a follow-up computed tomography scan that revealed a residual lump.

References

1. Zorob RJ, Campbell JS. Acute shortness of breath in the office. Ben Family Arts. Nov 2003;68(9):1803-10. Accessed: September 26, 2019.

2. Sahn SA, Heffner JE. Spontaneous pneumothorax. N Engl J Med. March 2000; 342 (12): 868-74. doi: 10.1056/NEJM200003233421207

3. Sajadi-Ernazarova KR, Martin J, Gupta N. Acute pneumothorax evaluation and treatment. Stat Pearls Publishing; 2020.

4. Yadav MK, Singhal M, Bhatia A, Kapoor R, Gupta N, Khandelwal N. Pleuropulmonary blastoma in adolescence: a rare tumor beyond the first decade of life. Long India. 2015;32(3):281-284. doi: 10.4103/0970-2113.156255

5. Zhang N, Zeng Q, Ma X, et al. Diagnosis and treatment of childhood pleuropulmonary blastoma: a single center report of 41 cases. J pediatric surgeon. 2019:doi:10.1016/j.jpedsurg.2019.06.009

6. Mlika M, El Mezni F. Cancer, pleuropulmonary blastoma. Stat Pearls Publishing; 2019.

7. Magistrelli P, D’Ambra L, Berti S, et al. Adult pulmonary blastoma: report of an unusual malignant lung tumor. World J Clin Oncol. Dec 2014;5(5):1113-6. doi:10.5306/wjco.v5.i5.1113

Comments are closed.