What is the treatment approach for hepatic spindle cell neoplasia?

Treatment Approach for Hepatic Spindle Cell Neoplasia

Complete surgical resection is the definitive treatment for hepatic spindle cell neoplasia, as these rare tumors respond poorly to chemotherapy and require complete excision for long-term survival. 1, 2

Diagnostic Considerations

Hepatic spindle cell neoplasms represent an extremely rare and heterogeneous group of tumors that pose significant diagnostic challenges both preoperatively and pathologically. These tumors include:

• Primary spindle cell tumors of the liver with smooth muscle differentiation, which may show positive staining for muscle markers (αSMA, desmin, h-caldesmon) 1
• Desmoplastic nested spindle cell tumors, characterized by cohesive nests of bland spindle cells in desmoplastic stroma with low mitotic activity 3, 2
• Unclassified malignant spindle cell neoplasms, which may display variable immunohistochemical profiles 4

The rarity of these tumors means preoperative imaging often misidentifies them as diaphragmatic tumors, sarcomas, or other hepatic masses, making definitive diagnosis dependent on surgical pathology. 1

Primary Treatment Strategy

Surgical Resection

Complete surgical resection with negative margins (R0 resection) is the cornerstone of treatment for all hepatic spindle cell neoplasms. 1, 3, 2

• Extent of resection should be determined intraoperatively based on tumor location and involvement of adjacent structures 1
• For tumors involving the hepatic capsule or adjacent diaphragm, combined resection of liver segments with diaphragmatic resection may be necessary to achieve complete excision 1
• Anatomical hepatectomy (segmentectomy or lobectomy) is preferred over wedge resection to ensure adequate margins 1
• Pediatric cases have shown excellent outcomes with complete resection alone, with patients remaining disease-free at 5-8 years post-surgery 3

Liver Transplantation

Liver transplantation should be considered for non-resectable tumors or cases where adequate liver remnant cannot be preserved. 2

• Transplantation is indicated when tumor size or location precludes safe resection with adequate future liver remnant 2
• This approach has been successfully employed for large desmoplastic nested spindle cell tumors that cannot be completely resected by conventional hepatectomy 2
• Transplantation provides the most complete tumor clearance while preserving hepatic function 2

Role of Adjuvant Therapy

Chemotherapy has limited to no role in the treatment of hepatic spindle cell neoplasms, as these tumors demonstrate poor chemosensitivity. 2

• Even in cases of recurrence or metastasis, these tumors respond poorly to systemic chemotherapy 2
• Some pediatric patients received postoperative adjuvant therapy based on misdiagnosis as hepatoblastoma, but this did not appear to influence outcomes 3
• The decision to pursue adjuvant therapy should only be considered in cases with high-grade features or incomplete resection, though evidence supporting benefit is lacking 4

Surveillance Protocol

Long-term imaging surveillance is mandatory due to the potential for late recurrence, even many years after initial complete resection. 2

• Follow-up imaging with CT or MRI should be performed every 3-6 months for the first 2 years, then extended to every 6-12 months thereafter 2
• Surveillance should continue indefinitely, as recurrence has been documented years after initial therapy 2
• Monitor for both local recurrence and distant metastases, though metastatic spread is uncommon 2

Critical Pitfalls to Avoid

• Do not rely on preoperative imaging alone for diagnosis—these tumors are frequently mischaracterized as extrahepatic masses or other hepatic lesions 1
• Do not attempt incomplete resection—partial debulking provides no survival benefit and these tumors do not respond to chemotherapy 1, 2
• Do not assume benign behavior based on low mitotic activity or bland cytology—even low-grade appearing tumors can recur or metastasize 4, 3
• Do not discontinue surveillance after 5 years—late recurrences have been documented, necessitating lifelong follow-up 2

Special Populations

For pediatric patients with desmoplastic nested spindle cell tumors, complete surgical resection alone has resulted in excellent long-term outcomes without need for adjuvant therapy, with disease-free survival extending beyond 7 years. 3

For post-transplant patients, malignant spindle cell neoplasms arising in liver allografts require aggressive surgical management with hepatectomy when feasible. 4