Discussion
To our knowledge, there has no previous review of literature reporting
on mediastinal cystic teratoma with pleural effusion. We find that
mature teratoma with pleural effusion presented a high proportion in
female patients during their young adult life. However, the literature
search demonstrates the occurrence of mature teratoma with pleural
effusion in patients as young as at 25 weeks of gestation and as old as
51 years.9–62 Respiratory symptoms are predominant
and not specific which has led often to a delay in the diagnosis for as
long as 2 years.9–11,19,20,22,28,30,32–61 The
majority of studies were reported in high-income countries. The
requirement for the diagnosis to be made by CT scan and histopathology
might explain the fact that such diagnosis is mostly reported in
high-income countries. Tissues found in the tumour appeared mostly
immature and of ovarian and pancreatic origin. Except from cases that
presented complications, the duration of hospitalisation was short with
variable lengths of follow-up periods. Complications related to
infections and metastases were reported in less than 10 cases. Relapses
occurred for some cases and death was a rare outcome and was reported in
10 cases due to respiratory complications
essentially.17,22,24,32
The major strength of our study is the systematic search of the
literature and the number of the cases reported. This will allow a more
systematic assessment of the prevalence of the disease and could raise
awareness among clinician from low and middle-income countries in
particular. Our results have highlighted a substantial proportion of
cases from low-income settings. Ascertainment misclassification
following difficulties to diagnose mediastinal cystic teratoma might
preside on the wrong impression of its rarity in poor settings.
Regarding the high burden of respiratory infection diseases in such a
region, clinicians might consider mediastinal tumours after an attempt
to treat an infection disease not specified otherwise.
Although a systematic search of literature through Medline, among
limitations of our study are the non-systematic search of ≥3 databases
and the exclusion of studies without full-texts. Another limitation was
related to the nature of the study that reported only on cases thus not
representative of the populations from which the cases came from.
However, the review has highlighted the need to consider such a
differential diagnosis when assessing a patient with signs of pleural
effusion especially in early childhood or young adult life.