What is the treatment approach for peroneal carcinomatosis?

Treatment Approach for Peritoneal Carcinomatosis

For peritoneal carcinomatosis, treatment should be tailored based on the specific clinicopathologic subtype, with platinum-based chemotherapy following optimal surgical debulking being the standard approach for females with serous histologic type adenocarcinoma, similar to FIGO III ovarian cancer. 1

Diagnostic Evaluation

Before initiating treatment, proper diagnosis and staging are essential:

1. Histopathological assessment:

   • Categorize the carcinoma into one of the following types:
     • Well or moderately differentiated adenocarcinoma
     • Poorly differentiated carcinoma
     • Squamous cell carcinoma
     • Undifferentiated neoplasm
     • Carcinoma with neuroendocrine differentiation 1

2. Immunohistochemistry:

   • Essential for poorly differentiated cases to exclude chemosensitive tumors
   • For adenocarcinoma, test for:
     • PSA in males
     • Estrogen and progesterone receptors in females with axillary node involvement
     • Keratins CK7 and CK20 to help identify possible primary site 1

3. Imaging and laboratory studies:

   • Thorough physical examination (including head, neck, rectal, pelvic, breast)
   • Basic blood work and biochemistry
   • CT scan of thorax, abdomen, and pelvis
   • Whole-body CT/FDG-PET may be beneficial, especially for single metastasis 1
   • Endoscopies should be symptom-guided

Treatment Strategy for Peritoneal Carcinomatosis

Female Patients with Peritoneal Carcinomatosis of Serous Histologic Type

1. Primary approach:

   • Optimal surgical debulking followed by platinum-based chemotherapy 1
   • Treatment should follow protocols similar to FIGO III ovarian cancer

2. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC):

   • Emerging evidence supports this approach for selected patients 1, 2
   • Best candidates have:
     • Good general health status
     • Limited intraperitoneal tumor dissemination (Peritoneal Cancer Index < 20)
     • Limited small bowel involvement
     • No extra-abdominal metastases 1

3. Patient selection criteria for CRS + HIPEC:

   • Completeness of cytoreduction is crucial for long-term benefit 3
   • Consider primary tumor location, histology, lymph node status, and response to systemic chemotherapy 1
   • Treatment should ideally be performed at specialized centers with experience in these procedures 4

Other Forms of Peritoneal Carcinomatosis

Treatment depends on the specific clinicopathologic subtype:

1. Poorly differentiated carcinoma with predominantly nodal disease:

   • Platinum-based combination chemotherapy 1

2. Poorly differentiated neuroendocrine carcinomas:

   • Platinum plus etoposide combination chemotherapy 1

3. Liver, bone or multiple-site metastases of adenocarcinoma:

   • Low toxicity palliative chemotherapy or best supportive care 1

Management of Complications

Malignant Bowel Obstruction

For patients with bowel obstruction due to peritoneal carcinomatosis:

1. Evaluate for surgical intervention or stenting based on clinical and radiological assessment 5

2. Symptomatic medications when surgery is not feasible:

   • Glucocorticoids
   • Antiemetic agents
   • Analgesics
   • Antisecretory agents (anticholinergic drugs, somatostatin analogues)
   • Consider venting gastrostomy if medications fail 5

3. Supportive care:

   • Rehydration for virtually all patients
   • Parenteral nutrition as needed
   • Pain management according to patient needs 5

Follow-up

• Response evaluation recommended after 2-3 chemotherapy cycles 1
• Imaging studies as appropriate based on treatment response
• No evidence that routine follow-up of asymptomatic patients is beneficial 1

Important Considerations

• The extent of intraperitoneal tumor dissemination and completeness of cytoreduction are the strongest predictors of outcome 2
• Peritoneal carcinomatosis was previously considered terminal, but aggressive multimodal approaches have improved survival in selected patients 6, 3
• Treatment at specialized centers with experience in cytoreductive surgery and HIPEC is recommended for optimal outcomes 4