In group 3 , the absorption dose per gram tumor tissue was 277 cGy , and 30 % tumor enlargement , 20 % died ; the remaining 50 % symptomatic improvement without any change in tumor size
Malignancy requires evidence of metastases at non-chromaffin sites distant from that of the primary tumor.
Metastatic disease in pheochromocytoma may be present at the time of initial diagnosis or may only became evident after surgical removal of the primary tumor, usually within 5 years, but sometimes 16 or more years later.
Literature Report
Therapy of Malignant Pheochromocytoma 恶性嗜铬细胞瘤的治疗
Introduction
rule of 10s for pheochromocytoma (PCC)
10% bilateral
10% extra-adrenal
10% extra-abdomen
Due to the rarity of the tumor, clinical studies about pheochromocytoma suffer from a fragmented nature and usually involve too small a number of cases to reach conclusive results.
Malignant vs. Benign
Currently, there is no effective cure for malignant pheochromocytoma.
There are also no reliable histopathological methods for distinguishing benign from malignant tumors.
Size does not reliably predict malignancy in pheochromocytomas with local disease only
Tumor size (mean ± SD) <2 cm 2.0-3.9 cm 4.0-5.9 cm 6.0-7.9 cm 8.0-9.9 cm ≥10 cm
Without treatment, the 5-year survival is generally less than 50%.
The course, however, can be highly variable with occasional patients living more than 20 years after diagnosis.
Primary surgical resection is the treatment of choice whenever possible
Limited disease: curative intention
Extended disease: still to be considered in the first place for debulking and as palliative treatment
10% malignant
10% familial来自10% children
10% normal blood pressure
Introduction
The most frequent site of metastases is the skeleton
Additional sites are liver, retroperitoneum with lymph nodes, CNS, pleura, and kidney
Should pheochromocytoma size influence surgical approach?
A comparison of 90 malignant and 60 benign pheochromocytomas
(Wen T. Shen et al.2004)
Comparison of tumor size for benign pheochromocytomas and malignant pheochromocytomas with local disease only
Once malignancy is diagnosed, therapy is generally directed at controlling blood pressure, but may also include tumor debulking.
Alternative of Current Therapy
Because there is currently no effective cure for malignant pheochromocytoma, most treatment are palliative, but in some cases may reduce tumor burden and prolong survival.
131 I-MIBG is of certain therapeutic effectiveness of symptomatic improvement
Complete tumor mass disappearance has only been found in small tumors
Treatment with 131 I-MIBG should be instituted immediately after surgical resection to eradicate the residual tumor cells and to prevent recurrences
Malignant (n = 29)
6.1 ± 3.1 cm 0 9 6 5 5 4
Benign (n = 55)
5.3 ± 2.3 cm 1 10 25 13 3 3
Malignant PCCs presenting with only local disease cannot be discriminated from benign PCCs by size alone.
Laparoscopic adrenalectomy for pheochromocytoma should be converted to open adrenalectomy for difficult dissection, invasion, adhesions, or surgeon inexperience
Surgical approach
Transabdominal approach is necessary minimally invasive procedures retroperitoneal approaches should be
abandoned to definitely preserve the tumor capsule and
(ZHU Ruisen et al. 1999)
Patients were classified into 3 groups according to their tumor size
< 8 cm3 (11 cases) , 8～20cm3 (21 cases) , > 20 cm3 (26 cases)
In group 1, the mean absorption dose per gram of tumor was above 1 000 cGy. After treatment ,tumors disappeared or shrinked in all patients
In group 2 , the absorption dose was similar to that of group 1, but the mean absorption dose per gram was 717.6 cGy , and tumor mass regression was 36 % ;76 % reduced urinary catecholamine
impossible Other treatment modalities have to be
considered
Alternative of Current Therapy
Surgery Radiopharmaceuticals Combined Chemotherapy Arterial Embolization
Surgery Radiopharmaceuticals Combined Chemotherapy Arterial Embolization
Alternative of Current Therapy
Surgery Radiopharmaceuticals Combined Chemotherapy Arterial Embolization
Bone marrow suppression is temporary and not dosage related
In 1997, Loh et al. published a review of the worldwide experience involving 116 patients treated with 131I-MIBG for malignant pheochromocytoma.