Intraepithelial carcinoma arising in an endodermal cyst of the posterior fossa

The imaging dynamic changes in the malignant transformation of an epidermoid cyst: a case report and literature review

Malignant transformation of epidermoid cysts is a rare complication. Most of the previously reported cases have involved postoperative malignant transformations. We present a case of malignant transformation of a nonpostoperative epidermoid tumor into squamous cell carcinoma (SCC) that occurred in a 61-year-old Chinese woman. The patient's initial cranial MRI scan showed an epidermoid cyst with marginal enhancement in the pre-pontine cistern, and the lesion gradually enlarged after 10 months. A craniotomy was performed using to remove part of the tumor via the right retrosigmoid approach, and postoperative pathology confirmed that the transformation of the epidermoid cyst was malignant. Our case study suggests that the possibility of malignant transformation of epidermoid cyst should not be ignored on the basis of enhanced imaging features, regardless of whether they are nodular, annular, or patchy, as is the case for inflammation. Strict follow-up is required for early detection of malignant transformation to prompt correspondingly early clinical treatment.

Adenocarcinoma arising in an ectopic enterogenous cyst: A rare case report and review of literature

Enterogenous cyst (EC) is a rare congenital lesion generally located in the central nervous system, such as in the cerebral hemispheres, posterior fossa, or spinal canal. They are usually benign lesions, and malignant transformation is rare. A 42-year-old woman felt an obvious pain in the lump and went to a local hospital for local lumpectomy. After 7 months, she again felt pain in the buttocks and difficulty in urinating and defecation. The computed tomography (CT) scan showed a mass in the pelvis. Sacrococcygeal cyst excision was performed 10 days later, and postoperative pathology showed epidermoid cyst. Shortly after, the patient recovered and was discharged from the hospital; the pain in the buttocks continued to recur. Puncture and drainage were performed five times. Later, the patient went to our hospital for treatment, and pelvic MRI showed multiple abnormal signal shadows in the presacral and sacrococcygeal regions, some of which were considered abscesses, and some were cystic lesions. She underwent tumor resection and was diagnosed with EC with locally moderately differentiated adenocarcinoma. Four months later, the patient's symptoms of swelling and pain recurred. MRI examination showed multiple high-signal T2 shadows in the anterior sacral and subcutaneous tissues of the buttocks, and enhanced scan showed partial marginal enhancement. After assessment, the patient was given a radiation dose of 60 Gy/25F. ECs in the anterior sacral and soft tissue of the buttocks are very rare, and the case of carcinomatous transformation has never been reported. Therefore, we discussed the clinicopathological features of ectopic ECs and reviewed the literature.

Elucidating the multiple genetic alterations involved in the malignant transformation of a KRAS mutant neurenteric cyst. A case report

Neurenteric cyst (NC) shows benign histopathology and rarely demonstrate malignant transformation. We herein describe a case of NC that exhibited malignant transformation. A 65-year-old female presented with gait disturbance due to compression by a cystic mass on the dorsal surface of the medulla oblongata. Partial resection was performed twice, leading to improvement of her symptoms. Two years after the second surgery, gadolinium-perfused T1-weighted magnetic resonance imaging revealed an invasive lesion with contrast enhancement at the trigone of the left lateral ventricle for which partial resection followed by radiotherapy was performed. However, mass regrowth was observed, with the patient eventually succumbing to her disease 11 months after her third surgery. Histopathological analyses of the first and second surgical specimens identified pseudostratified cuboidal epithelial cells, with no nuclear or cellular atypia resembling gastrointestinal mucosa, lining the inner surface of the cystic wall. Based on these findings the lesion was diagnosed as NC. The third surgical specimen exhibited apparent malignant features of the epithelial cells with elongated and hyperchromatic nuclei, several mitotic figures, small necrotic foci, and a patternless or sheet-like arrangement. Based on these findings, the lesion was diagnosed as NC with malignant transformation. Next-generation sequencing revealed KRAS p.G12D mutation in all specimens. Additionally, the third surgical specimen harbored the following 12 de novo gene alterations: ARID1A loss, BAP1 p.F170L, CDKN1B loss, CDKN2A loss, CDKN2B loss, FLCN loss, PTCH1 loss, PTEN loss, PTPRD loss, SUFU loss, TP53 loss, and TSC1 loss. The aforementioned results suggest that KRAS mutation is associated with the development of the NC, and that the additional gene alterations contribute to malignant transformation of the NC.

Pediatric intracranial neurenteric cyst of the oculomotor nerve: a case-based review

BACKGROUND

Neurenteric cysts (NECs) of the central nervous system (CNS) are uncommon congenital entities arising from embryonal elements. Intracranial NECs in the pediatric population are rare.

METHODS

The authors describe the presentation, radiographic imaging, and pathologic findings of an 11-year-old boy with a right oculomotor nerve NEC. A literature review was performed to identify additional cases of pediatric intracranial NECs published in the English language, over the past 30 years (1990-2020). The authors discuss the presentation, investigations, management, and prognosis of this interesting entity.

RESULTS

We describe an 11-year-old boy who presented to neurosurgical attention with disconjugate gaze, anisocoria, and ptosis. Magnetic resonance imaging (MRI) demonstrated a lobulated, cystic, and peripherally enhancing mass involving the right oculomotor nerve. The patient underwent pterional craniotomy for drainage of the cyst and subtotal resection of the cyst wall. The tan-colored mass was displacing the basilar artery, compressing the cerebral peduncle, and adherent to the inferior surface of the tentorium. The lesion was within the oculomotor nerve and splitting the fibers, and the cystic contents were thick and mucinous. Histopathological examination of the specimen demonstrated a thin fibrous cyst wall with scattered inflammatory cells and lined by simple columnar epithelium containing mucin. The lining cells were immunoreactive with epithelial membrane antigen (EMA) and pan-keratin AE1/AE3. The diagnosis of a NEC was rendered. A comprehensive literature review of pediatric intracranial NECs yielded 46 additional lesions published in the literature, involving the skull base, posterior fossa, cerebral convexity, and cranial nerves. NECs present with local mass effect and less commonly, with aseptic meningitis or intracystic hemorrhage. Maximal safe GTR remains the mainstay management, although cyst drainage and marsupialization, cyst shunting, and fenestration of cystic contents into the ventricle or basal cisterns have been reported with variable success.

CONCLUSION

CNS NECs are rare congenital entities; although they occur less frequently in the intracranial components compared to the spine, their diagnosis and management should be considered for intracranial cystic lesions. Maximal safe GTR is the mainstay treatment and frequently yields favorable outcomes.

Endodermal Cysts of the Central Nervous System: Review of the Literature and a Case Report

Context

Endodermal cysts are rare benign developmental cysts lined by mucin-secreting and/or ciliated, cuboidal, or columnar epithelium of probably endodermal origin.

Aims

Endodermal cysts are rarely intracranial, frequently located in the posterior fossa. Supratentorial location is the most infrequent and only few cases are reported in the literature, included our case.

Settings and Design

The authors report a case of intracranial supratentorial endodermal cyst with a review of the literature.

Subjects and Methods

A 40-year-old woman was admitted to our department because of progressive gait disorder for 3 months due to right brachial and crural motor deficit associated to right crural sensory disorder (tactile hypesthesia) and right Babinski response at neurological examination due to an endodermal cyst located in the left frontoparietal convexity.

Discussion

Total resection of endodermal cysts is recommended, despite their location and adhesion to the surrounding structures, due to its high risk of recurrence. Fenestration of the cystic content into the subarachnoid cistern may cause obstructive hydrocephalus or chemical meningism.

Results

Although rare, surgeons should be aware that these lesions must be differentiated clinically, radiologically, and histologically from other supratentorial cystic lesions.

Neurenteric cysts at foramen magnum in children: presentation, imaging characteristics, and surgical management-case series and literature review

INTRODUCTION

Neurenteric cysts (NEC) are rare benign tumors of the central nervous system. Even more rare are the NEC at the ventral foramen magnum in children that are misdiagnosed. They cause distortion of the vertebrobasilar vascular system and cervicomedullary neural structures and are adherent to the latter. The inferior portion lies ventral to the upper most dentate ligament. This has implications in the surgical approach for complete excision.

METHODS AND CASE SERIES

We reviewed our series of five children with ventral foramen magnum NEC in the MRI era and analyzed presentation, radiological findings and surgical management. A literature review is also presented.

RESULTS

There were two females and five males. Headache and neurological deficit was present in all five; one child presented with recurrent meningitis. The NEC was present ventral to the cervicomedullary junction in all cases. The posterolateral transcondylar approach was used for complete excision with no recurrences.

CONCLUSIONS

Neurenteric cysts at the ventral foramen magnum can be confused with other cystic lesions. Headaches are the most common presentation. The posterolateral transcondylar approach to the ventral cervicomedullary junction provides the most reliable avenue for entire resection.

Intracranial neurenteric cyst mimicking an ependymoma: imaging features, pathologic correlation and review of literature

We present a case of a 57-year-old female with four-months of diplopia and vertigo. MRI revealed a mixed cystic and solid partially enhancing lesion of the 4th ventricle, foramen of Luschka and cerebellopontine angle. Preoperative differential diagnosis favored ependymoma. Biopsy revealed a neurenteric cyst, a benign developmental lesion that rarely occurs intracranially. This case highlights several atypical manifestations of intracranial neurenteric cyst, with regions of histologically benign solid enhancement, multicompartmental extra-axial location mimicking an ependymoma, and rapid recurrence without evidence of underlying malignancy.

Mucinous adenocarcinoma arising from a residual supratentorial neurenteric cyst and expressing mutated KRAS: a case report

Malignant transformation of intracranial neurenteric cysts (NCs) has been reported in only 7 cases, but the molecular characteristics leading to malignant transformation remain unclear. A 61-year-old woman presented with headache and dizziness. Imaging revealed a 10-cm, extra-axial cystic mass in both middle fossae. A partial resection was performed, and the residual mass size gradually decreased. She had repeated ventriculoperitoneal shunts to relieve symptoms of hydrocephalus. Eight years later, follow-up images revealed marked enlargement of the mass and a newly developed lesion. After a second partial resection, a mucinous adenocarcinoma infiltrating the brain was identified. Transitions from benign-looking cuboidal cells to dysplastic cells were observed. A KRAS mutation, which might be associated with malignant NC transformation and was not present in the initial specimen, was identified in the adenocarcinoma. In conclusion, KRAS-mutant mucinous adenocarcinoma may arise in a longstanding residual NC after partial resection.

Recurrent intracranial neurenteric cyst with malignant transformation: A case report and literature review

Neurenteric cysts (NCs) are uncommon congenital cystic lesions. Malignantly transformed NCs are extremely rare. The present study reports the case of a recurrent foramen magnum NC with a malignant transformation and reviews 8 previously reported cases. A 58-year-old woman with a 5-month history of occasional headaches, dizziness and vomiting presented to the Beijing Tiantan Hospital (Beijing, China) with palsy of the left cranial IX and X nerves, decreased sensation in the limbs on the right side and an ataxic gait. Magnetic resonance imaging (MRI) scans revealed a cystic mass in the left side of the foramen magnum, positioned anteriolaterally to the medulla oblongata. Surgery using a left suboccipital retrosigmoid approach was performed. The lesion was partially resected and was histopathologically diagnosed as an NC with focal hyperplasia of the epithelial cells. Additional MRI scans that were performed 25 months later revealed a solid lesion posterior to the medullar oblongata. Therefore, surgery using a suboccipital midline approach was performed. The solid lesion was sub-totally removed and was histopathologically diagnosed as a well-differentiated papillary adenocarcinoma. At 1 month post-surgery, the patient's condition worsened, eventually resulting in mortality due to respiratory failure. Based on the findings of the present case and previous literature, strict criteria for malignant-transformed NCs were created. The location distribution of malignant-transformed NCs does not coincide with the location distribution of all NCs, and malignantly transformed NCs usually occur in adult patients and present as atypical radiological features. Surgery is the optimal treatment for malignantly transformed NCs, and the effectiveness of adjuvant therapy requires additional studies.

Non-metastatic squamous cell carcinoma within a Rathke's cleft cyst

INTRODUCTION

Primary intracranial and sellar squamous cell carcinoma is an extremely rare entity, usually caused by malignant transformation of epidermoid cysts, or very rarely other non-malignant epithelial cysts. Malignant transformation of a Rathke's cleft cyst has never been described.

CASE DESCRIPTION

We present a 49-year-old male patient who presented with a 3-month history of progressive frontotemporal headaches. Imaging revealed a 1.2 cm cystic pituitary mass consistent with a hemorrhagic Rathke's cleft cyst. The patient underwent trans-sphenoidal resection of the pituitary cyst, and pathologic analysis revealed a squamous cell carcinoma lining a Rathke's cleft cyst. Extensive imaging and otorhinolaryngologic evaluation revealed no primary source for metastasis.

CONCLUSIONS

We feel this represents the first case of a patient with a pituitary lesion in which presentation and MRI imaging were consistent with Rathke's cleft cyst, yet histology revealed squamous cell carcinoma in situ.

Malignant Transformation of a Neurenteric Cyst in the Posterior Fossa Presenting with Intracranial Metastasis: A Case Report and Literature Review

Intracranial neurenteric cysts are relatively rare and almost exclusively benign. Here we present a case of an intracranial neurenteric cyst that was histologically benign in the first surgery and later demonstrated significant growth and intracranial metastasis with malignant transformation. A 47-year-old woman presented with a headache, which had gradually worsened over 1 year. Initial magnetic resonance (MR) images revealed a solitary cystic lesion in the left cerebellopontine angle with significant mass effect. Subtotal resection leaving a small mass strongly adhered to the brainstem was achieved. Histopathological diagnosis was neurenteric cyst with no malignant features. This lesion recurred 4 years after the first surgery in the form of a cystic mass adjacent to the brainstem. In addition, histopathological examination of a specimen from the second surgery revealed malignant transformation. The patient declined to undergo radiation therapy and was conservatively managed. Three years after the second surgery, MR imaging showed recurrence of the solid mass. Although the patient had been treated with subtotal resection and radiation therapy, she died with metastatic masses in the right frontal lobe and cervical cord. A specimen from the third surgery revealed diffuse malignant features similar to mucinous adenocarcinoma. Our case and literature review indicate that, although rare, malignant transformation can occur particularly among intracranial neurentreric cysts. This finding suggests the importance of long-term follow-up for subtotally or partially resected intracranial neurenteric cysts.

Mucinous adenocarcinoma arising from supratentorial intramedullary neuroenteric cyst with broncho-pulmonary differentiation

Neuroenteric cysts are benign intradural endoderm cysts lined by gastrointestinal (GI) or tracheobronchial epithelial cells. Their malignant transformation is extremely rare and only six cases have been reported. In these cases, tissue lineage of the cystic endoderm cells giving rise to carcinoma was not clearly identified either as respiratory or as GI type. Herein, we report a case of mucinous adenocarcinoma arising from the neuroenteric cyst with broncho-pulmonary differentiation in the right cerebral hemisphere of a Japanese woman in her late 50s. The cyst wall was entirely lined by the following respiratory epithelial components: stratified bronchial ciliated columnar epithelium with basal cells positive for CK5 and p63, terminal bronchiolar Clara cells positive for thyroid transcription factor (TTF)-1, surfactant B and negative for surfactant C, type I pneumocytes positive for TTF-1, negative for surfactant B and C, and type II pneumocytes positive for TTF-1 and surfactant B and C. In addition, nests of hyperplastic single layered mucinous epithelial cells with bronchial goblet cell phenotype were also demonstrated, and histologic features were almost the same as the pulmonary type I congenital adenomatoid malformation (CCAM) with mucinous epithelial proliferation. The mucinous epithelial nests of type I CCAM are liable to develop mucinous adenocarcinoma and frequently accompany K-ras mutation and expression of p16. However, K-ras mutation and p-16 expression were not detected in this case.

An analysis of intracranial epidermoid tumors with malignant transformation: treatment and outcomes

OBJECTIVE

While typically benign, epidermoid tumors upon rare occasion can undergo malignant transformation, which carries a poor prognosis. Here, we reviewed treatment strategies and analyzed outcomes for every case of malignant epidermoid tumor reported since its original description in 1912.

METHODS

A comprehensive literature review identified all reported cases of malignant transformation of intracranial epidermoid tumor. Treatments were categorized as follows: palliative management, stereotactic radiosurgery (SRS), chemotherapy, and surgery plus multiple (2+) adjuvant therapies. Survival data of these groups were compared to treatment outcomes for patients receiving only surgical resection, as reported in our previous study.

RESULTS

We identified 58 cases of intracranial epidermoid tumor with malignant degeneration. Average survival regardless of therapy was 11.8 months. Mean survival outcomes for groups treated with palliative management, chemotherapy, SRS, and multiple postoperative adjuvant therapies were 5.3 months, 25.7 months, 29.2 months, and 36.3 months, respectively. Outcomes for the groups including SRS, chemotherapy, and multiple post-operative adjuvant therapies were statistically significant compared to surgical resection alone.

CONCLUSION

While there remains a lack of consensus regarding the best approach to the management of patients with malignant epidermoid tumors, our systematic analysis characterizes and confirms the added benefit of SRS, chemotherapy, and multimodal adjuvant therapies.

Survival outcomes for radiotherapy treatment of epidermoid tumors with malignant transformation

Epidermoid tumors are intracranial lesions that may occasionally undergo malignant transformation. Although surgical resection is the first-line treatment for malignant epidermoids, postoperative radiotherapy has been intermittently reported with favorable findings. Our analysis identified all previously reported patients with malignant epidermoids treated with surgical resection alone or surgery plus radiotherapy to examine the potential role for this adjuvant therapy. Whereas patients treated with surgery only had an overall survival of 6.6 months, those treated with postoperative radiotherapy demonstrated a statistically significant increase in survival to 12.7 months (log-rank test, p<0.003). Furthermore, the mean dosage of radiation given to this patient population was 52.2 Gy, with no appreciable survival benefit for the utilization of levels of radiation greater than 50 Gy. When determining the management for malignant transformation of epidermoid tumors, the combination of surgical resection and radiotherapy may be associated with improved short-term survival.

Endoscopic transsphenoidal, transclival resection of an enterogenous cyst located ventral to the brainstem: case report

BACKGROUND AND IMPORTANCE

Enterogenous cysts are rare tumors found most commonly in the spine, but they have also been reported intracranially. Cases of enterogenous cysts located within the posterior fossa have traditionally been resected via difficult craniotomies that require prolonged retraction and risk injury to cranial nerves. We describe a method for resection of an enterogenous cyst located anterior to the brainstem via the endoscopic transsphenoidal approach.

CLINICAL PRESENTATION

A 37-year-old man was found to have a 2-cm mass anterior to the brainstem during routine screening after a trauma. The mass was located within the prepontine cistern, enhanced with gadolinium contrast, and showed no restrictive diffusion. This lesion was most consistent with an enterogenous cyst. A minimally invasive endoscopic endonasal transsphenoidal transclival approach was performed for gross total resection of the tumor.

CONCLUSION

We discuss the endoscopic transsphenoidal approach used for the resection of an enterogenous cyst in the posterior fossa anterior to the brainstem. The transsphenoidal approach provides direct access to lesions in this location using a minimally invasive technique while avoiding excessive brain retraction or injury to cranial nerves. In addition, we provide an updated review of the literature for enterogenous cysts located within the posterior fossa.

Neurenteric cyst with xanthomatous changes in the prepontine area: unusual radiological findings

Preoperative diagnosis of neurenteric cysts can be difficult because the imaging findings of a neurenteric cyst may be similar to those of an arachnoid cyst. The authors report a case of a neurenteric cyst with xanthomatous changes in the prepontine area. This 4-year-old girl was admitted to their institution with intermittent neck pain and vomiting. Computed tomography showed a hypodense mass in the prepontine area. Magnetic resonance imaging showed a cystic lesion measuring approximately 4 x 3 cm. The brainstem was displaced posteriorly, and the cisterns in both cerebellopontine angles were widened. The signal intensity of the cyst was similar to that of cerebrospinal fluid. Adjacent to the basilar artery there was a solid component of the mass that enhanced after administration of Gd. Intraoperatively, the authors found a cystic mass containing clear fluid with a yellowish solid nodule. On the basis of histopathological findings, the lesion was diagnosed as a neurenteric cyst with xanthomatous changes.

MUCINOUS LOW-GRADE ADENOCARCINOMA ARISING IN AN INTRACRANIAL ENTEROGENOUS CYST

OBJECTIVE

Enterogenous cysts (ECs) of the central nervous system are developmental malformations that occur in the spinal canal, posterior fossa, or cerebral hemispheres. They are usually benign lesions, and malignant transformation is rare. To date, only three cases of malignant transformation have been reported in the literature. We present a case of a cerebellopontine EC showing foci of epithelial dysplasia and malignant transformation into a low-grade papillary mucinous adenocarcinoma.

CLINICAL PRESENTATION

A 25 year-old man with a 6-year history of hypoacusia presented to our department with facial nerve deficit, visual disturbances, and gait instability. A magnetic resonance imaging scan demonstrated a multiloculated cerebellopontine angle cyst with supratentorial hydrocephalus.

INTERVENTION

A retrosigmoidal approach was used to achieve cyst removal. This was followed several months later by ventriculoperitoneal shunt placement. The cyst was adherent to the brainstem, cranial nerves, and vessels, and it resembled a thin encapsulated structure filled with mucinous-like substance. No solid component was identified. Histopathological examination revealed an EC with foci of malignant transformation in a mucinous papillary adenocarcinoma. Magnetic resonance imaging was performed 5 months postoperatively due to progressive clinical worsening; this scan revealed lesion recurrence with severe brainstem compression. Emergency surgery was performed, and a large decompression was achieved. Subsequent follow-up computed tomographic scans showed progression of the residual tumor. The patient's neurological condition rapidly worsened, ultimately resulting in death.

CONCLUSION

The present report suggests that a careful histological examination of all ECs after surgery should be made to exclude dysplastic foci or carcinomatous transformation. Although the clinical behavior of ECs with malignant trasformation is unpredictable, surgery remains the treatment of choice. The use of possible adjuvant chemo- or radiotherapy has not been established.

Endodermal cyst of the cranio-cervical junction

We reviewed 36 patients with endodermal cysts occurring at the craniocervical junction. They were aged between 3 and 66 years. Headache, motor weakness, and neck pain were commonly observed symptoms. Radiographically, T1-weighted magnetic resonance imaging of the tumours demonstrated a hypointense, isointense, or hyperintense signal according to the cystic content. In most cases, the cyst walls did not enhance after gadolinium administration. Histologically, the cysts were found to be lined by a single layer of epithelium. Histochemical and immunohistochemical studies showed that almost all were reactive to periodic acid schiff stain, epithelial membrane antigen, and carcino-embryonic antigen, but negative to glial fibrillary acidic protein. Mainly, the suboccipital approach with or without a laminectomy, or the trans-oral approach were selected for surgical excision of these tumours. In 17 of the 36 patients, total or gross total resections were performed, and subtotal resections were achieved in sixteen. Three patients developed recurrences.

Endodermal Cyst of the Oculomotor Nerve: Case Report

OBJECTIVE:

Endodermal cysts are commonly found in the anterior spinal cord. Reports of intracranial cases are uncommon. We report a case of endodermal cyst located on the left oculomotor nerve.

CLINICAL PRESENTATION:

A 16-year-old female experienced diplopia followed by headache. Neurological examinations revealed left oculomotor nerve palsy. Magnetic resonance imaging scans showed a well-defined multilocular cystic mass in the proximity of the left oculomotor nerve at its exit from the midbrain.

INTERVENTION:

This patient underwent biopsy and drainage of the cyst. At surgery, the cyst seemed to be intrinsic to the oculomotor nerve and could not be totally resected. Pathological examination confirmed the diagnosis of endodermal cyst.

CONCLUSION:

Intracranial endodermal cysts are rare, particularly when associated with the cranial nerves. To our knowledge, this is the second case of endodermal cyst located on the oculomotor nerve. A detailed discussion and review of these case reports are presented.

Malignant transformation of intra-cranial epithelial cysts: systematic article review

INTRODUCTION

Epidermoid and dermoid cysts are among the most benign intra cranial tumors. Their malignant transformation into squamous cell carcinoma is rare. The authors reviewed the literature.

MATERIALS AND METHODS

MEDLINE and SCIENCE DIRECT searches, and examination of the references in the selected articles yielded 74 patients, 52 of whom fulfilled Garcia's criteria and were selected for the study. Survival analyses were performed to determine whether survival differences were of statistical significance, and P < 0.05 was considered as significant.

RESULTS

Malignant transformation is characterized by a rapid onset of symptoms, recurrence, leptomeningeal carcinomatosis (LC), and tumor enhancement at Computed Tomography Scan or Magnetic Resonance Imaging (87.8 showed this radiological feature). In this review, the SCCs were classified in five groups: (1) Initial malignant transformation of a benign cyst; (2) malignant transformation from a remnant cyst; (3) malignant transformation of a dermoid and epithelial cyst; (4) malignant transformation with leptomeningeal carcinomatosis; (5) other malignancies arising from benign cysts. The median survival was 9 months. Statistics show that LC was of poor prognosis and radiotherapy, although not statistically significant, seems effective against such lesions, with a median survival of 26 months as opposed to 3 months (P=0.077).

CONCLUSION

Although rare, malignant transformation of intracranial epithelial cysts has a poor prognosis and surgery followed by radiotherapy seems to be the best therapeutic modality.