Jonathan C. Trent, MD, PhD: Additional Chemotherapy in This Patient

How has the availability of targeted therapies influenced treatment options for patients with leiomyosarcoma?

This patient has received first-, second-, and third-line chemotherapy regimens that are standard of care for patients with advanced leiomyosarcoma. A newer agent, termed trabectedin, has been shown in a randomized study to be superior to dacarbazine in terms of progression-free survival.

In this patient, I would use as the next line of therapy trabectedin, given as 1.5 m/g²continuous infusion every 3 weeks.

CASE: Soft-Tissue Sarcoma (Part 1)

Rachel F is a 58-year-old school teacher from Roanoke, Virginia. Her medical history is notable for mild hypertension and total knee replacement in 2011

• In March of 2013, she presented to her PCP with abdominal fullness and distension of several months’ duration; physical exam showed mild abdominal discomfort on palpation; she denied any recent weight loss
• Initial abdominal sonography was inconclusive; subsequent CT scan showed a heterogeneously enhancing retroperitoneal mass along segment I of the inferior vena cava (IVC) and central necrosis
• She underwent contrast-enhanced CT with coronal and sagittal reconstructions, which showed encasement of the aorta and multiple hepatic metastases
• CT guided biopsy of the mass showed leiomyosarcoma that was immunohistochemically positive for desmin, smooth muscle actin, and vimentin, with a high proliferative rate (Ki67 > 60%)
• She underwent chemotherapy with gemcitabine and docetaxel for a total of 6 cycles, and experienced a minor response. Therapy was discontinued however, in November 2013 due to cumulative toxicity

Follow-up CT scan in January 2014 showed progression at multiple sites; at the time of follow up, her ECOG performance status was 1, with renal and hepatic function within normal limits

• She underwent six cycles of chemotherapy with anthracycline and dacarbazine, and her disease stabilized

In September of 2014 she returns for follow-up, unable to work with increasing fatigue and abdominal pain, and her CT scan was consistent with progressive disease

• She received treatment with pazopanib at 800 mg daily for metastatic disease
• Patient tolerated the treatment well, with mild fatigue and diarrhea, and her symptoms improved

After 4 months of therapy, she presents with worsening abdominal pain and declining performance status

• CT showed extensive progression of the primary tumor and hepatic metastases
• At progression, CBC, liver, and renal function were within normal limits, ECOG performance status was 2