Background: Low-grade endometrial carcinoma has an excellent prognosis. The risk of secondary cancer after endometrial carcinoma is moderately increased and is mostly related to the field of postoperative radiation (small intestine, colon, vagina, and urinary bladder). Anaplastic (undifferentiated) pelvic carcinoma (APC) is rare and probably under-reported. To date, only one publication has reported six cases of APC that were secondary to low-grade endometrial carcinoma.
Case report: We have analyzed the fulminant course of APC-preceded by paraneoplastic arthritis-four months after hysterectomy and adnexectomy for low-grade endometrial carcinoma (endometrioid type, moderately differentiated, tumor diameter: 2 cm, infiltration depth 3 of 15 mm). The 73-year-old patient died five weeks after the diagnosis of the second malignancy.
Conclusion: The prognosis of APC is poor and the limitations of the therapy result from aggressive tumor biology and rapid deterioration of the patients' general condition. Rheumatological symptoms can precede cancer diagnosis. Immunohistochemistry facilitates the differentiation between primary and secondary carcinoma.
Keywords: Anaplastic carcinoma; endometrial cancer; paraneoplastic arthritis; secondary cancer.