Primary mediastinal germ cell tumours with high prevalence of somatic malignancy: An experience from a single tertiary care oncology centre

Ann Diagn Pathol. 2021 Aug:53:151763. doi: 10.1016/j.anndiagpath.2021.151763. Epub 2021 May 26.

Abstract

Background: Primary mediastinal germ tumours (PMGCT) constitute, a mere 3-4% of all germ cell tumours (GCT). Although they account for approximately 16% of mediastinal tumours in adults and 19-25% in children as per western literature, there is hardly any large series on PMGCT reported from the Indian subcontinent.

Design: We have retrospectively analysed clinicopathological features of 98 cases of PMGCT diagnosed over 10 years (2010-2019) from a tertiary-care oncology centre.

Results: The study group (n = 98) comprised predominantly of males (n = 92) (M:F ratio-15:1), with an age range between 3 months to 57 years (median: 25 years). The tumours were predominantly located in the anterior mediastinum (n = 96). Broadly, Non-seminomatous germ cell tumours (NSGCT) were more common (n = 73, 74%) compared to pure seminoma (n = 25, 26%). Mixed NSGCT was the most common histological subtype (n = 30) followed by pure mature teratoma (n = 18), pure Yolk sac tumour (n = 13), mixed seminoma and NSGCT (n = 5), pure immature teratoma (n = 3) and GCT; NOS (n = 4). Interestingly, all female patients had exclusive teratomas. Nine cases revealed secondary somatic malignancy (5 carcinomas and 4 sarcomas). The majority of patients received neoadjuvant chemotherapy (n = 71). Surgical excision was performed in 60 patients. Follow up was available in 68 patients. NSGCT showed a poor prognosis as compared to seminoma (p value = 0.03) and tumours with somatic malignancies had a more aggressive clinical course.

Conclusion: PMGCT was seen predominantly in young adult males and somatic malignancies were noted in as high as 9% of cases. Patient with somatic malignancy have aggressive clinical course, hence, extensive sampling and careful histopathological evaluation are recommended for the identification and definitive characterization.

Keywords: Non-seminomatous germ cell tumour; Primary Mediastinal germ cell tumour; Seminoma; Somatic malignancy.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Endodermal Sinus Tumor / diagnosis
  • Endodermal Sinus Tumor / epidemiology
  • Endodermal Sinus Tumor / pathology
  • Humans
  • India / epidemiology
  • Infant
  • Male
  • Mediastinal Neoplasms / pathology*
  • Middle Aged
  • Neoadjuvant Therapy / methods
  • Neoplasms / epidemiology
  • Neoplasms, Germ Cell and Embryonal / diagnosis*
  • Neoplasms, Germ Cell and Embryonal / epidemiology
  • Neoplasms, Germ Cell and Embryonal / pathology
  • Neoplasms, Germ Cell and Embryonal / therapy
  • Oncology Service, Hospital / organization & administration
  • Prevalence
  • Prognosis
  • Retrospective Studies
  • Seminoma / diagnosis*
  • Seminoma / epidemiology
  • Seminoma / pathology
  • Teratoma / diagnosis
  • Teratoma / epidemiology
  • Teratoma / pathology
  • Tertiary Healthcare
  • Testicular Neoplasms / diagnosis*
  • Testicular Neoplasms / epidemiology
  • Testicular Neoplasms / pathology
  • Young Adult

Supplementary concepts

  • Nonseminomatous germ cell tumor