Thymoma / Thymic carcinoma 229

46. Thymoma / Thymic carcinoma

46.1 General considerations

Thymomas originate within the epithelial cells of the thymus; They also contain admixtures or (bengin) lymphocytes . Thymic carcinoma is also believed to be a tumor of the thymic epithelium, but it is associated with a paucicity of lymphocytes and often presents with more invasive or metastatic disease.

Masaoka staging system of thymomas (adapted)

Stage Description

I Macroscopically completely encapsulated with no

microscopic extracapsular invasion

IIA Microscopic invasion through the capsule

IIB Macroscopic invasion into mediastinal fat or pleura

III Macroscopic invasion into adjacent structures (i.e.

pericardium, great vessels, or lung)

IVA Pleural or pericardial metastases

IVB Lymphogenous or hematogenous metastases

For the majority of patients with localized thymomas surgery is the principal treatment . The rate of failure after complete resection of encapsulated disease is considerably low. Local control and survival seem to be improved by adjuvant radiotherapy in more advanced, but respectable disease. Chemotherapy can be offered to patients with locally advanced, recurrent, or metastatic thymoma, with responses in 50-80 % of patients and prolonged survival .

The optimal coordination of chemotherapy, radiation therapy, and surgery in a multimodality approach has yet to be defined.

Literature: for review e.g.

GIACCONE, Ann. Oncol. 11 (Supple. 3) ( 2000) : 245-246

JOHNSON et al, Oncologist 6(2001): 239- 246

LARA, Cancer Treat. Rev. 26 (2000): 127 – 131

LOEHRER and WICk, Cancer Treat Res, 105 (2001): 277 – 302

MULLER- HERMELINK and MARX, Curr. Opin. Oncol. 12 (2000):

426-433

THOMAS et al, J. Clin. Oncol. 17 (1999) : 2280 – 2289

46.2 thymoma

46.2.1 PAC

Cisplatin 50mg/m2 i.v.(1 h inf ) d 1

Doxorubicin 50mg/m2 i.v. (bolus) d 1

Cyclophosphamide 500 mg/m2 i.v. (bolus) d 1

To be repeated every 3 weeks ( 2-4 cycles, followed by radiotherapy as induction

therapy)

Literature:

LOEHRER et al, J. Clin. Oncol. 15(1997): 3093- 3099

230                                                                                                               Thymoma/ Thymic Carcinoma

46.2.2 ADOC

Doxorubicin 40mg/m2 i.v. (bolus) d 1

Cisplatin 50mg/m2 i.v. ( 1 h inf) d 1

Vincristine 0.6 mg/m2 i.v. (bolus) d 2

Cyclophosphamide 700 mg/m2 i.v. (bolus) d 4

To be repeated every 3 weeks ( 3-6 cycles as induction therapy)

Literature:

BERRUTI et al, Br. J. Cancer 81 (1999) : 841-845

46.2.3. PE

Cisplatin 60mg/m2 i.v. ( 1 h inf) d 1

Etoposide 120 mg/m2 i.v. (30 min inf) d 1-3

To be repeated every 3 weeks

Literature:

GIACCONE et al, J. Clin. Oncol. 14 (1996): 814 – 820

46.2.4 ifosfamide

Ifosfamide 1500mg/m2 i.v. (30 min inf) d 1-5

With mesna uroprotection

To be repeated every 3 weeks

Literture:

HIGHLEY et al, J. Clin. Oncol. 17 (1999): 2737 – 2744

46.3. Thymic carcinoma

Treatment can be tried with cisplatin-based regimens used in germ cell tumors (e.g. BEP).

Literature:

WEIDE et al, Cancer 71 (1993): 1219 – 1223