Autologous Bone Marrow Transplantation - Blog Science Connections

ABMT for Breast Cancer 493
Table 3. Treatment Results
Patient Therapy Response Duration (mo) Survival (mo)
1 Cy150 PR 4 18
2 Cy200 MR 15 19
3 Cy200 PR 8 20
4 Cy200 PR 3 9
5 Cy200 NE — 0.5
6 Cy200 NR — 2.5
7 CyBCNU PR 2 4
8 CyBCNU NR 2
9 CyBCNU CR 7 9+
10 CyBCNU CR 2 3
Abbreviations: Cy150, cyclophosphamide (150mg/kg); Cy200, cyclophosphamide
(200 mg/kg); CyBCNU, cyclophosphamide (160 mg/kg) plus BCNU (carmustine) (900
mglm 2 ); CR, complete response; PR, partial response; MR, minor response; NR, no
response; NE, not évaluable.
Because no CRs were achieved by the first six patients, cyclophosphamide
was reduced 20% and carmustine was added for patients 7 through
10. Three of the four responded, and two had clinical CRs. However, only
patient 9 had a response of significant duration, and she relapsed with
multiple brain metastases after 7.5 months. The other two patients relapsed
locally after short responses. In the entire series, six of the seven responders
relapsed locally, suggesting inadequate tumor cytoreduction rather than a
contribution by tumor-contaminated autologous marrow.
For the most part, response durations were disappointingly short. The
median duration of response was 4 months, and only three patients had
unmaintained responses in excess of 6 months.
Neither the type of pretransplant therapy nor the performance status
seemed to influence response rate in this small group of patients. Four of the
five patients who had previously received only adjuvant chemotherapy
responded, including both of those achieving CR, while three of the five
patients who had failed standard-dose combination chemotherapy for
measurable metastases achieved PRs with the high-dose regimens. Four of
five with a pretransplant performance status of 0 or 1 responded, while three
of five responded whose performance status was 2 to 4. Nevertheless,
transplant-related morbidity was greater in the patients with a poor performance
status.
DISCUSSION
Preliminary evidence suggests a steep dose-response relationship for
cytotoxic chemotherapy for metastatic breast cancer (3,4). The technique of
stem-cell autografting provides for the testing of this hypothesis without the
dose-limiting toxicity of irreversible marrow suppression. Studies using this