Carcinoid

Epidemiology

General

  • One to 6% of all lung tumors are carcinoid tumors.
  • 40-50 years average age of presentation
  • 1 or 2 cases per 100,000 annually.
  • trend of relative increase of pulmonary carcinoids.

Risk Factors

  • Most familial pulmonary carcinoids have been reported in patients with MEN1
  • Atypical and typical lung carcinois have loss of 11q-13 which harbors the MEN1 gene.

Presentation and Evaluation

Pathology

  • most indolent form neuroendocrine tumors (ex. small cell carcinoma)
  • Atypical tumors have no distinguishing gross characteristics that may be used to differentiate them from typical carcinoids.

Clinical Presentation

  • Cough
  • Dyspnea
  • Infection, fever
  • Asymptomatic

Neoplastic Syndroms

  • Serotonin syndrome is characterized by tachycardia, flushing, bronchoconstriction, hemodynamic instability, diarrhea, and acidosis, is reported in 2-12% of patients with bronchial carcinoid tumors.
  • Ectopic ACTH is the second most common neuroendocrine syndrome produced by these tumors
  • Syndrome of inappropriate secretion of ADH (SIADH) can be produced by pulmonary carcinoid tumors, although it more commonly is associated with small cell lung carcinoma.

Routes of Spread

  • Well-differentiated carcinoids are indolent with 3%-15% nodal or distant spread
  • Atypical have 30%-57% nodal and 20% distant metases risk.
  • Most common sites of distant metastasis are liver, bone adrena., brain, skin and soft tissue.

Staging

Treatment

Surgery

  • Complete resection if possible for non-metastatic disease.
  • Lymph node dissection should accompany resection

Medical Therapy

  • No medical therapy exists for the primary treatment of carcinoid tumor of the lung.
  • Chemotherapeutic agents and radiation therapy have been used in the treatment of metastatic disease but have met with virtually no success.
  • A response rate of 30-35% has been reported using a combination of 5-fluorouracil and streptozotocin.
  • Symptomatic relief of carcinoid syndrome from metastatic disease has been achieved by administration of octreotide, which can be administered subcutaneously.

Radiation Therapy

Adjuvant radiation has been used for

  • > 3 cm tumors
  • positive nodes
  • positive margins
  • atypical histology
  • residual disease
  • inoperable disease

Technique

  • PTV includes
  • gross or residual tumor and tumor bed with 1.5 to 2.0 cm margin
  • subclinical and regional lymphatics are included.

Dose
Post-op: 45-58 Gy in conventional fractionation
Gross disease: may be higher.

Outcome

Prognostic Factors

Summary

resected carcinods OS-5
All carcinoids 78% to 100%
typical carcinoids 90%-100%
atypical carcinoids 25% to 69%
metastatic carcinoids 18% to 38%
  • OS-10 are 10% to 20% lower

Studies

Bibliography
1. full source reference
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-Share Alike 2.5 License.