PLACENTAL METASTASIS

1. From Fetal Malignancies.
• Neuroblastoma (1).
• Leukemias (2).
• Congenital giant pigmented nevi (3,4).
2. From Maternal Malignancies (transplacental).
• Leukemia / Lymphoma.
• Melanoma (about half of the malignant melanomas metastatic to the placenta are also metastatic to the fetus) (5-8).
• Sarcomas (9)
• Breast.
• Ovarian tumors (10).
3. Metastasis of malignancy to products of conception is rare.
• Malignant melanoma is the most common of these, accounting for nearly 30%.
• Leukemia, lymphoma, and breast adenocarcinoma combined account for an additional 30% (11).

4. Metastasis to the fetus occurs in only 27% of these cases in which products of conception are involved. Eighty percent of the cases are associated with malignant melanoma or hematopoietic malignancies (11).

REFERENCES

1. Perkins DG, Kopp CM, Haust MD. Placental infiltration in congenital neuroblastoma: A case study with ultrastructure. Histopathology 1980;4:383-389.
2. Fox H. Pathology of the placenta. Philadelphia, PA, Saunders 1978:362.
3. Holaday WJ, Castrow FF. Placental metastasis from a giant pigmented nevus. Arch Dermatol 1968;98:486-488.
4. Demian SDE, Donnelly WH, Frias JL et.al. Placental lesions in congenital giant pigmented nevi. J Clin Pathol 1974;61:438-442.
5. Potter JF, Schoenman M. Metastasis of maternal cancer to the placenta and fetus. Cancer 1970;25:380-388.
6. Aronsson S. A case of transplacental tumor metastasis. Acta Pediatr Scand 1963;52:123-124.
7. Russel P, Laverty CR. Malignant melanoma metastasis in the placenta: A case report. Pathology 1977;9:251-255.
8. Cavell B. Transplacental metastasis of malignant melanoma. Acta Pediatr Scand 1963 (suppl);146:37-40.
9. Weber FP, Schwartz E, Hellenschmeid R. Spontaneous inoculation of melanotic sarcoma from mother to fetus. Br Med J 1930:537.
10. Horner EN. Placental metastasis. Case report: Maternal death from ovarian cancer. Obstet Gynecol 1960;15:566.
11. Read EJ, Platzer PB. Placental metastasis from maternal carcinoma of the lung. Obstet Gynecol. 1981;38:387-391.