Primary Intracranial Epidermoid Carcinoma with Diffuse Leptomeningeal Carcinomatosis: Report of Two Cases

Malignant Transformation of an Intracranial Epidermoid Cyst 25 Years After Initial Surgery: A Case Report and Systematic Review

OBJECTIVE

We report a unique case of a suspected recurrent intracranial epidermoid cyst (EDC) that was found on pathology to have undergone malignant transformation to squamous cell carcinoma (SCC) approximately 25 years after initial resection. Additionally, we performed a systematic review including 94 studies reporting intracranial EDC to SCC transformation.

METHODS

Ninety-four studies were included in our systematic review. PubMed, Scopus, Cochrane Central, and EMBASE were searched in April 2020 for studies regarding histologically confirmed SCC arising within an EDC. Kaplan-Meier estimations were used to estimate time to event including survival, and log rank tests were used to test for significance. All analyses were conducted using STATA 14.1 (StataCorp, College Station, Texas, USA); tests were two-sided, and statistical significance was defined using the alpha threshold of 0.05.

RESULTS

The overall median time to transformation was 60 months (95% confidence interval {CI}, 12-96). Transformation time was significantly shorter in the no surgery group (10 months, 95% CI undefined) versus the other 2 groups (60 months, 95% CI, 12-72 in surgery only and 70 months, 95% CI, 9-180 in surgery + adjuvant therapy group, both P < 0.01). Overall survival was significantly longer in the surgery + adjuvant therapy group (13 months, 95% CI, 9-24) versus the other 2 groups (3 months, 95% CI, 1-7 in surgery only and 6 months, 95% CI, 1-12 in the no surgery group, both P < 0.01).

CONCLUSIONS

We report a rare case of delayed malignant transformation of an intracranial EDC to SCC, occurring nearly 25 years after initial resection. Transformation time in the no-surgery group was statistically significantly shorter as compared to the surgery only and surgery + adjuvant therapy groups. Overall survival was statistically significantly higher in the surgery + adjuvant therapy group as compared to the surgery only and no surgery groups.

Primary Squamous Cell Carcinomas Arising in Intracranial Epidermoid Cysts: A Series of Nine Cases and Systematic Review

Objective

Primary squamous cell carcinomas (PSCCs) arising in intracranial epidermoid cysts (IECs) are very rare, and their management and prognostic factors remain unclear. This study aimed to enunciate the clinical features and suggest a treatment protocol based on cases from the literature and the cases from our institution.

Methods

The clinicoradiological data were obtained from nine patients with PSCCs arising in IECs, who underwent surgical treatment at Beijing Tiantan Hospital between July 2012 and June 2018. We also searched the PubMed database using the keywords “epidermoid cyst(s)” or “epidermoid tumor(s)” combined with “malignant” or “malignancy” or “intracranial” or “brain” or “squamous cell carcinoma” between 1960 and 2020. Risk factors for overall survival (OS) were evaluated in the pooled cohort.

Results

The mean age of our cohort was 51.2 ± 8.3 years (range: 39–61 years), which included eight males and one female. Gross total resection (GTR) was achieved in three patients, while non-GTR was achieved in six patients. Radiotherapy was administered to five patients. After a median follow-up of 16.7 ± 21.6 months (range: 3–72 months), eight patients died with a mean OS time of 9.75 ± 6.6 months (range: 3–23 months). In the literature between 1965 and 2020, 45 cases of PSCCs arising in IECs were identified in 23 males and 22 females with a mean age of 55.2 ± 12.4 years. GTR, non-GTR, and biopsy were achieved in six (13.3%), 36 (80%), and three (6.7%) cases, respectively. After a mean follow-up of 12.7 ± 13.4 months (range: 0.33–60 months), 54.1% (20/37) patients died, and recurrence occurred in 53.6% (15/28) patients. A multivariate analysis demonstrated that postoperative radiotherapy (p = 0.002) was the only factor that favored OS. The Kaplan–Meier analysis showed that, compared with no radiotherapy (median survival time: 4 months), radiotherapy (median survival time: 24 months) had significantly prolonged OS (p = 0.0011), and GTR could not improve OS (p = 0.5826), compared with non-GTR. The 1-year OS of patients with or without radiotherapy was 72.5% or 18.2%, respectively.

Conclusion

Malignant transformation of IEC into PSCC was prevalent in elderly patients, with slight male predominance. GTR of previous benign IECs is recommended. For remnant benign IECs, close follow-up should be performed. Postoperative radiotherapy for PSCCs could bring survival benefit. GTR of these malignant intracranial tumors is difficult when they involve important brain structures. Future studies with larger cohorts are necessary to verify our findings.

Long-term surgical outcomes of intracranial epidermoid tumors: impact of extent of resection on recurrence and functional outcomes in 63 patients

OBJECTIVE

The authors' objective was to reevaluate the role of microsurgery for epidermoid tumors by examining the associations between extent of resection (EOR), tumor control, and clinical outcomes.

METHODS

This was a retrospective study of patients with microsurgically treated intracranial epidermoid tumors. The recurrence-free and intervention-free rates were calculated using the Kaplan-Meier method. EOR was graded as gross-total resection (GTR) (total resection without residual on MRI), near-total resection (NTR) (a cyst lining was left in place), subtotal resection (STR) (> 90% resection), and partial resection (PR) (any other suboptimal resection) and used to stratify outcomes.

RESULTS

Sixty-three patients with mean clinical and radiological follow-up periods of 87.3 and 81.8 months, respectively, were included. Sixteen patients underwent second resections, and 5 underwent third resections. The rates of GTR/NTR, STR, and PR were 43%, 35%, and 22%, respectively, for the initial resections; 44%, 13%, and 44% for the second resections; and 40%, 0%, and 60% for the third resections (p < 0.001). The 5- and 10-year cumulative recurrence-free rates after initial resection were 64% and 32%, respectively. When stratified according to EOR, the 10-year recurrence-free rate after GTR/NTR was marginally better than that after STR (61% vs 35%, p = 0.130) and significantly better than that after PR (61% vs 0%, p < 0.001). The recurrence-free rates after initial microsurgery were marginally better than those after second surgery (p = 0.102) and third surgery (p = 0.065). The 5- and 10-year cumulative intervention-free rates after initial resection were 91% and 58%, respectively. When stratified according to EOR, the 10-year intervention-free rate after GTR/NTR was significantly better than that after STR (100% vs 51%, p = 0.022) and PR (100% vs 27%, p < 0.001). The 5-year intervention-free rate after initial surgery was marginally better than that after second surgery (52%, p = 0.088) and significantly better than that after third surgery (0%, p = 0.004). After initial, second, and third resections, permanent neurological complications were observed in 6 (10%), 1 (6%), and 1 (20%) patients, respectively. At the last follow-up visit, 82%, 23%, and 7% of patients were free from radiological recurrence after GTR/NTR, STR, and PR as the initial surgical procedure, respectively.

CONCLUSIONS

GTR/NTR seems to contribute to better disease control without significantly impairing functional status. Initial resection offers the best chance to achieve better EOR, leading to better disease control.

Primary Intracranial Squamous Cell Carcinoma with a Fatal Course

Intracranial squamous cell carcinomas (SCCs) are extremely rare. They can be primary or represent a degeneration of an epidermoid cyst (EC). We report the case of a patient operated, with an endoscopic transnasal approach, for a primary intracranial SCC. The optimal management for patients with primary intracranial SCC or ECs which have undergone malignant degeneration has yet to be identified.

Primary Intracranial Malignant Epidermoid with Multiple Metastases in Internal Organs: A Rare Autopsy Case

Primary intracranial malignant epidermoids are rare, with most cases developing from a pre-existing benign epidermoid cyst. We report a case involving a rare autopsy finding of a primary intracranial malignant epidermoid in the brainstem with cerebellopontine angle (CPA) involvement. A 53-year-old woman with double vision was diagnosed with right abducens palsy. At her visit to our hospital 3 months after the onset of the first symptom, she presented left hypoglossal nerve paralysis and truncal ataxia in addition to right abducens palsy. Magnetic resonance imaging (MRI) revealed a mass lesion (2-cm long and 3-cm thick) in the left CPA that exhibited gadolinium enhancement. Moreover, gadolinium-enhanced magnetic resonance imaging (MRI) revealed abnormal multiple brainstem and supratentorial mass lesions with partial enhancement. Whole-body computed tomography failed to identify any possible primary lesion. Following a tentative diagnosis of an epidermoid cyst with an assumption that the tumor was highly aggressive, we performed subtotal surgical resection of the CPA tumor. Histological findings revealed a malignant epidermoid in the CPA lesion. Although the patient underwent radiation and chemotherapy after the surgical resection, she died of respiratory failure 10 months after the onset of symptoms. Herein, we report the rare clinical course and autopsy data, and discuss the characteristic features of this rare condition.

Genomic profile of a primary squamous cell carcinoma arising from malignant transformation of a pineal epidermoid cyst

Malignant transformation of intracranial epidermoid cysts is a rare occurrence. We present the second case of such an event occurring in the pineal region and the first case sent for detailed genomic profiling. MRI demonstrated two lesions: a cyst in a quadrigeminal cistern with restricted diffusion on DWI-weighted images and an adjacent, peripherally enhancing tumor with cerebellar infiltration. Both the lesions were completely resected with a small residual of the epidermoid cyst. The final pathology of both lesions was consistent with epidermoid cyst and squamous cell carcinoma (SCC), respectively. The tumor specimen was sent for comprehensive genomic profiling which revealed stable microsatellite status and loss of CDKN2A/B, MTAP (exons 2-8), and PTEN (exons 6-9). Although reports of primary SCC originating from the epidermoid cyst have been previously described, this is the first description of the genomic profile of such a tumor.

Microsurgical Treatment of Epidermoids. Case Report and Literature Review

The aim of the research: study the features of surgical treatment of epidermoids.

Materials and methods. We present a literature review and the clinical case of surgical treatment of a patient with epidermoid. We have searched medical databases: Medline, Russian Science Citation Index, EMedicine, United Medical Knowledge Base. We considered the features of the clinic, diagnosis, and surgical intervention. The article presents a clinical example of successful surgical treatment of a patient with an epidermoid cyst of the posterior cranial fossa. The result of the literature review was the writing of a clinical lecture; the current state of the issue of etiopathogenesis, diagnosis and management of patients with epidermoids was studied.

Results. The authors found that total microsurgical removal is the method of choice, and the operative technique should be aimed at preventing postoperative aseptic meningitis. Although it was not possible to establish the cause of the development of aseptic meningitis, the authors assume that the mechanism of its formation lies in the self-breaking of the capsule of the epidermoid cyst, probability of which was confirmed by a number of studies. Further study of this pathology is a promising direction in neurosurgery.

Conclusion. Difficulties in the diagnosis and choice of surgical tactics point at the need for detailed preoperative planning of surgical intervention, performing a precise total removal of a lesion with compliance with preventive measures for aseptic meningitis to improve clinical results and reduce the incidence of perioperative complications.

Malignant squamous cell carcinoma arising in a previously resected cerebellopontine angle epidermoid

Background:

Malignant squamous cell differentiation of an epidermoid cyst can carry a significantly poor prognosis and very little is known about this entity.

Case Description:

We present the case of a 35-year-old lady, with primary malignant squamous cell carcinoma (SCC) arising from a previously partially resected cerebellopontine angle epidermoid cyst almost 5 years after initial resection. We also review the relevant literature.

Conclusion:

The imaging findings, histopathology, and management of a malignant SCC arising from a benign epidermoid cyst are discussed with recommendation for increased surveillance and follow-up, even for classically accepted benign lesions.

Complete endoscopic resection of a pituitary stalk epidermoid cyst using a combined infrasellar interpituitary and suprasellar endonasal approach: case report

Intracranial epidermoid cysts are benign lesions of epithelial origin that most frequently present with symptoms of mass effect. Although they are often associated with a high rate of residual tumor and recurrence, maximal safe resection usually leads to good outcomes. The authors report a complete resection of an uncommon pituitary stalk epidermoid cyst with intrasellar extension using a combined suprasellar and infrasellar interpituitary, endoscopic endonasal transsphenoidal approach. The patient, a 54-year-old woman, presented with headache, visual disturbance, and diabetes insipidus. Postoperatively, she reported improvement in her visual symptoms and well-controlled diabetes insipidus using 0.1 mg of desmopressin at bedtime and normal anterior pituitary gland function. One year later, she continues to receive the same dosage of desmopressin and is also taking 50 mcg of levothyroxine daily after developing primary hypothyroidism unrelated to the surgical procedure. A combined infrasellar interpituitary and suprasellar approach to this rare location for an epidermoid cyst can lead to a safe and complete resection with good clinical outcomes.