DISEASE CHARACTERISTICS: Histologically or cytologically proven medullary thyroid carcinoma Unresectable local-regional disease OR Distant metastases Autologous peripheral blood stem cells (PBSC) or bone marrow available Diffuse bone/marrow involvement allowed if: Autologous bone marrow or PBSC with no greater than 5% tumor involvement available Radiation dose to marrow no greater than 3000 cGy until 6 patients have been treated safely at that dose level At least 1 site confirmed by CT targeted by pretherapy indium In 111 monoclonal antibody MN-14 imaging

PATIENT CHARACTERISTICS: Age: 16 to 80 Performance status: Karnofsky 60-100% ECOG 0-2 Life expectancy: At least 3 months Hematopoietic: WBC at least 3000/mm3 Granulocyte count at least 1500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 2 mg/dL Renal: Creatinine less than 1.5 times upper limit of normal Cardiovascular: Ejection fraction at least 50% Other: No severe anorexia, nausea, or vomiting No concurrent significant medical complications that would preclude compliance Not pregnant Fertile patients must use effective contraception during and for 3 months after study

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since biologic therapy Chemotherapy: At least 4 weeks since prior chemotherapy and recovered No greater than 240 mg/m2 doxorubicin total for combination therapy with doxorubicin but no greater than 550 mg/m2 doxorubicin if radioimmunotherapy alone No prior failure on doxorubicin therapy for combination therapy but not radioimmunotherapy alone Endocrine therapy: Prior synthroid (T4) allowed Radiotherapy: See Disease Characteristics At least 4 weeks since prior radiotherapy to index lesion and recovered No prior radiotherapy to greater than 35% of red marrow Surgery: At least 4 weeks since prior major surgery