Article
removal of the lesion. Intraoperatively it was found that the lesion was separated from the adrenal gland. This finding to- gether with the pathologic report of a neoplasia invading the capsule, not going beyond it, and images of venous invasion made the diagnosis of malignant paragan- glioma. Genetic screening of the patient demonstrated a new germinal frameshift mutation of the SDHB exon 6 [c.587- 591DelC]. There was a family history of a cousin diagnosed at 13 years of age with a dopamine producing malignant paragan- glioma, that died at 30 years of age with wide spread metastasis [cranial and lum- bar].
In the post operative period there was
a normalisation of VMA, catecholamines and metanephrines concentrations. On March 2006 routine analyses showed an elevation of catecholamines. Abdominal MRI showed a recidiva that was confirmed by MIBG cintylogram. The patient under- went a new surgical removal of the tumour. Pathologic report confirmed this to be a local metastasis of the previous paragan- glioma. Once again there was a normalisa- tion of the analytical parameters after sur- gery but 12 months after this episode she started complaining of back pain. Analyti- cal evaluation showed a new elevation of VMA and catecholamines concentrations. This time scintigraphy revealed a solitary hyperfixation on T11 [Figure 1]. CT con- firmed a lytic lesion on the body of T11 extending to the left pedicle [Figure 2]. On MRI this lesion presented low signal in T1 WI and high signal in T2 WI and enhanced after gadolinium injection. These features were suggestive of a probable metastasis [Figure 3]. The patient was referred to the Spine Group of our hospital and tumour removal was decided. She underwent an intralesional tumour excision and corpec- tomy, and replacement with an interbody spacer [Synex, Synthes], autologous graft and a lateral plate [Vantage, Medtronic] [Figure 4]. The pathologic analysis of the lesion confirmed a new recidiva of para- ganglioma. After surgery there was a fa- vorable evolution with improvement of the clinical symptoms and normalisation of the analytical parameters and imagi- ologic screening. The patient was able to resume work. She was kept under tight medical surveillance and one year later she presented with new positive image in the lumbar region, corresponding to
Figure 1. Cintigraphy revealing a solitary hyperfixation on T11.
a new image in the pedicle of T11 in the contralateral side of the surgical incision. She performed 2 treatments with MIBG [6660 MBq [180 mCi] of MIBG 131] that made the new lesion diminish and after- wards 1 cicle of radiotherapy. The patient resumed her daily living with no limita- tions, and without any present clinical or analytical evidence of new metastasis. The prevalence of catecholamines or metanephrines secreting tumours in cas- es of hereditary pheochromocytoma and paraganglioma disorders is 10–20% in pa- tients with von Hippel–Lindau disease, ap- proximately 40% in patients with multiple endocrine neoplasia type 2A and 2B, and 0.1–5.0% in patients with neurofibromato- sis type 16,7
.
The incidence of pheochromocytoma is 0.001 in the general population. There aren’t reports stating the real incidence of paragangliomas, but it is consensual that it
is far bellow the incidence of pheocromo- cytoma. The malignant diagnosis is noted according to whether metastasis or inva- sion exists.
Paragangliomas are commonly bilateral and may be multicentric. Multicentricity occurs in approximately 10% of tumours. Paragangliomas characteristically have a slow and unpredictable growth pattern, making it difficult to determine the natural history of the disease3
.
There are five types of familial para- ganglioma [PGL] syndromes that
have
been identified with mutations in the SDH genes that encode subunits of the hetero- tetrameric SDH complex. SDH is involved in oxidation of succinate to fumarate in the Krebs cycle and provides electrons to the mitochondrial electron transport chain6
.
Investigation has revealed that SDHD mutations [PGL type 1] are associated with multifocal head and neck paragangliomas,
Autumn 2012 | SpinalSurgeryNews | 21
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36