Treatment for paraganglioma with stereotactic radiotherapy

Table 1 Classification of paragangliomas

Glasscock-Jackson classification			Fisch classification		Shamblin classification
	TPG	JPG		JPG		Carotid PG
Type 1	Small mass limited to the promontory	Involves jugular bulb, middle ear, mastoid process	Type A	Limited to middle ear cleft	Type 1	Tumors are localized with minimal vascular attachments. These are easily amenable to complete resection with very little morbidity
Type 2	Tumor completely filling the middle ear	Extends under canal, with or without intracranial extension	Type B	Limited to the tympanomastoid area; cortical bone over jugular bulb intact	Type 2	Tumors partially surround the carotids. These are careful surgical excisions
Type 3	Tumor filling middle ear and mastoid	Extends into petrous apex with or without intracranial extension	Type C (C1-C2-C3)	Involving the infralabyrinthine compartment and petrous apex of the temporal bone	Type 3	Tumors encase the carotids. Surgical resection is difficult and may require major vessel reconstruction
Type 4	Further extension through the EAC or anteriorly to the carotid artery	Extends beyond petrous apex into clivus or infratemporal fossa, with or without intracranial extension	Type D (D1-D2-D3)	Glomus jugular tumors with intracranial extensions

TPG: Tympanic paraganglioma; JPG: Jugular bulb paraganglioma; PG: Paraganglioma; EAC: External auditory canal.

Table 2 Patients characteristics

Patients	Age (yr)	Site of origin	Fisch classification	Glasscock-Jackson classification	Surgery	Volume (mL)	Dose (Gy)	Isodose (%)	Fraction	Pathogenesis
1	20	TPGs	D	3	No	12.4	21	75	3	Sporadic
2	60	Cervical spine	\	\	No	20.2	20	77	5	SDHB mut
3	68	JPG	D	3	No	12.7	20	73	3	Sporadic
4	44	JPG	C	2	No	14.5	21	76	3	Sporadic
5	84	JPG	D	3	No	64.24	25	70	5	Sporadic
6	74	JPG	D	3	No	10.99	30	82.5	5	Sporadic

TPG: Tympanic paraganglioma; JPG: Jugular bulb paraganglioma.

Table 3 Summary of patient outcome

Patients	OS (months)	PFS (months)	Response treatment
1	180	144	PD
2	156	96	PR
3	72	72	PR
4	72	72	PR
5	5	5	NA
6	6	6	PR

OS: Overall survival; PFS: Progression free survival; PD: Progression disease; PR: Partial response; NA: Not available.

Table 4 Characteristics of the analyzed studies

Ref.	PGs Resectable	Embolization	Median dose (Gy)	Isodose (%)	Median fractions	Technique	Median volume (mL)/ size (cm)	Outcome
Fatima et al[45]	Yes (NA)	Yes (NA)	15	NA	1-5	CK-GKS-LINAC	8.4 mL	94.2% LC
Patel et al[47]	Yes (10/26)	Yes (1/26)	16	NA	1	GKS	7090 mL	NA
Ehret et al[48]	Yes (20/53)	Yes (8/53)	16.5	70	1	CK	4.3 mL	100% 5-year LC
Marchetti et al[31]	Yes (NA)	No	12.6	78.6	1	CK	3.6 mL	33% LC (35 months)
			25	80	5		16.1 mL
Tosun et al[49]	Yes (NA)	No	24	75	3	CK	35.5 mL	100% LC
Lieberson et al[50]	24/12		20	80	1-5	CK	4.64 mL	100% LC
Dupin et al[51]	Yes (21/81) No (60/21)	Yes (1/81)	25	\	25	60Co machine/ LINAC	30 mL	100% 5-year LC; 98.7% 10-year LC
Main et al[30]	Yes (1/1)	Yes (1/1)	\	\	\	\	93.553 mL	NA
López-Arcas et al[52]	Yes (1/1)	Yes (1/1)	14		2	CK	4 cm	NA
This study	No	No	21	75.5	4	CK	13 mL	100%

PG: Paragangliomas; NA: Not available; CK: Cyberknife System; GKS: Gamma Knife System; LINAC: Linear accelerator; LC: Local control.