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Spontaneous regression of a posterior fossa meningioma: A case report
Maya Takada1, Kiyoyuki Yanaka1, Kazuhiro Nakamura1
1Department of Neurosurgery, Tsukuba Memorial Hospital, Tsukuba, Japan.
Background:
Since most incidentally discovered meningiomas grow or remain unchanged, spontaneous regression is extremely rare. Here, we report a case of posterior fossa meningioma showing spontaneous regression.
Case Description:
A 55-year-old female was referred to our hospital because she was diagnosed with a left posterior fossa meningioma (diameter: 1.6 cm) during a brain check-up. The patient was followed up on periodic magnetic resonance imaging studies. Tumor size remained almost unchanged for 2 years but then began to regress. Twelve years after the initial examination, the tumor diameter idiopathically decreased from 1.6 cm to 1.1 cm while the tumor volume decreased from 2.3 cm3 to 0.5 cm3 (about 1/4th the original size). Postmenopausal hormonal imbalances may have been associated with the observed spontaneous regression.
Conclusion:
Understanding the natural history of meningiomas is essential for a better selection of treatment approaches or appropriate follow-up. This case may provide new insights into the progression of meningiomas.
Insights
Spontaneous regression of posterior fossa meningioma is rare. This case study documents significant tumor shrinkage over 12 years, potentially linked to hormonal changes.
Area of Science:
- Neuro-oncology
- Neurosurgery
- Radiology
Background:
- Meningiomas are typically slow-growing tumors, with most incidentally discovered ones remaining stable or increasing in size.
- Spontaneous regression of meningiomas is an exceptionally rare phenomenon, challenging conventional understanding of their natural history.
Observation:
- A 55-year-old female presented with a left posterior fossa meningioma (1.6 cm diameter).
- Initial follow-up showed stable tumor size for two years.
- Over twelve years, the meningioma demonstrated idiopathic regression, decreasing in diameter from 1.6 cm to 1.1 cm and volume from 2.3 cm³ to 0.5 cm³.
Findings:
- The posterior fossa meningioma exhibited substantial spontaneous regression over a decade.
- Postmenopausal hormonal imbalances are hypothesized as a potential contributing factor to the observed regression.
Implications:
- This case highlights the possibility of spontaneous regression in meningiomas, even in the posterior fossa.
- Understanding such rare events can refine management strategies and follow-up protocols for meningioma patients.
- Further research into the mechanisms of meningioma regression may offer novel therapeutic insights.
