The rare form of the central nervous system includes a rosette forming glioneuronal tumor. The case reports and the literature is sparse regarding this cancer. The glial and neurolytic components are mixed and the rosette forming glioneuronal tumor is benign. Adult patients aged 30 years or above are diagnosed with this rare condition.
The description of rosette forming glioneuronal tumor was classified under dysembryoplastic neuroepithelial cancer, which is located in the cerebellum. Around 11 cases were reported back in 2002, which was misdiagnosed initially. Later, with the diagnostic tests, a rosette glioneuronal tumor was indicated.
In 2007, WHO classified it as a low-grade tumor that is not malignant. The pineal region, fourth ventricle, cervical spinal cord, and hypothalamus are the areas commonly affected by rosette forming glioneuronal tumors. The histogenesis of this cancer is still not clear and needs further investigation.
Rosette Forming Glioneuronal Tumor Grades
The grading system of tumors is consistently upgraded by the World health organization (WHO). Grade unknown is a new category that was updated specifically for glioneuronal tumors. However, The tumor grades are differentiated according to several factors and most importantly the patient’s condition. Other than this the morphological characteristics are important to consider, for instance,
- Mitotic activity
- Cytological Atypia
- Microvascular proliferation can also include the proliferation of endothelial cells.
These factors divide the tumor into four grades. For your convenience, we have briefly explained each grade. Keep reading further:
- GRADE 1
No criteria are met in this grade. The growth of the tumor is slow and there is no malignancy. The survival chances in this phase are highest if the tumor is diagnosed at an early stage.
- GRADE 2
Cytological atypia is the only criteria met by the tumor in grade 2. They are high-grade tumors when they recur but at the same time, the growth is not rapid. Either the tumor at this stage can be benign or malignant.
- GRADE 3
The two criteria are met by the tumors in grade 3. One is mitotic activity while the other is anaplasia. The grade 3 tumors are higher-grade cancer and they progress to malignancy.
- GRADE 4
All the criteria are fulfilled in grade 4 tumors including necrosis. They are highly malignant and aggressive forms of tumors. The treatment at this stage is perplexing.
Rosette Forming Glioneuronal Tumor Symptoms
Symptoms of rosette forming glioneuronal tumors are not specified. Ataxia and headache are the commonly seen symptoms in patients suffering from this form of cancer. Gastrointestinal disturbances that include nausea and vomiting can also be experienced.
Truth to be told, the signs and symptoms of rosette forming glioneuronal tumors vary according to the condition of the patient. It also depends on the tumor grade. A more aggressive nature can have symptoms that might reject medication therapy and deteriorate the quality of life.
Pilocytic astrocytoma is the differential diagnosis in this case and it is often confused with a rosette forming glioneuronal tumor.
Rosette Forming Glioneuronal Tumor Radiology
The solid cystic components of rosette forming glioneuronal tumors are the main features observed with the radiological exams. 40% of the tumor is solid entirely. Whereas 35% of cases can occur as mixed versions, that means solid and cystic features. However, 25% of the patients may present with cystic characteristics only.
The biphasic nature of immunohistochemistry is consistent. The identification of glial and neurolytic patterns helps to differentiate from other tumors associated with the central nervous system. The CT scan results of the tumor revealed that the appearance of the tumor is variable. In quarter cases, calcification is seen.
Moreover, the MRI scan demonstrates solid components and a high level of T2 signal. Gadolinium enhancement is commonly seen with a rosette forming glioneuronal tumors.
Rosette Forming Glioneuronal Tumor Prognosis
The local parenchymal extension is seen in the 4th ventricle region, in the case of a rosette forming glioneuronal tumor. Astrocytic and neurolytic components are commonly seen with the tumor. The prognosis of a rosette forming glioneuronal tumor is dependent on the condition of the patient.
Initially, there is a possibility that the tumor can be confused with other nervous system tumors. CT scan and MRI are most commonly used to detect rosette forming glioneuronal tumors. These midline tumors are rare and are not common among the various tumors.
Rosette Forming Glioneuronal Tumor Treatment
Additional treatment therapy is required with surgical approaches. Surgery alone will not be helpful to treat rosette forming glioneuronal tumors. The recurrence rate in the patients diagnosed with this tumor is moderate. This means that surgery can be an option but radiotherapy and chemotherapy should be considered for some time after or before surgery.
The effective management of rosette forming glioneuronal tumors is still controversial. The clinical literature is not evident regarding a single treatment. The adjuvant treatment plans include chemotherapy and radiotherapy. Proton beam therapy is also effective in a few cases.