autologous blood and marrow transplantation - Blog Science ...

404 Chapter 7: Solid Tumors
chemotherapy [partial or complete response]) and their extent of disease (limited or
extensive stage) were provided in the published reports. While not part of a formal
meta-analysis, patients in these various categories were pooled for aggregated
relapse-free and overall survival characteristics.
Fifty-two patients with relapsed or refractory disease achieved complete and
partial responses in 19 and 37%, respectively, in 14 small studies. 25-38
The median
response durations and survivals were about 2-4 months. Combination
chemotherapy regimens, especially those containing multiple alkylating agents,
were slightly more effective (response rate 58%, CR 26%), but more toxic (18 vs.
6% deaths). The high complete response rate substantiates a dose-response
relationship, but was insufficient for cure.
One hundred three patients with untreated SCLC (71% limited disease) received
single- or double-cycle high-dose therapy as initial treatment. Overall and complete
response rates of 84 and 42% were achieved. 39
^ 16
Relapse free, 2-year, and overall
survivals were comparable to treatment with conventional multicycle regimens.
Seven percent achieved durable remissions. Transplantation in the newly
diagnosed SCLC setting is potentially hazardous because of the frequency of lifethreatening
complications from uncontrolled disease and the likelihood of tumor
cell contamination in untreated autografts. On the other hand, early intensification
may have greater impact on the disease.
Approximately 344 patients in response to first-line chemotherapy received
high-dose chemotherapy with autologous marrow support as consolidation. 47-63
Conversion from partial to complete response occurred in 40-50%, but without
durable effect. In patients with limited disease in complete response at the time of
high dose therapy, 35% remained progression-free at a median follow-up >3 years
at the time of publication.
One randomized trial has been reported. 60
Of 101 patients with SCLC who
received five cycles of conventional chemotherapy with prophylactic cranial
irradiation (PCI), 45 (45%) were eligible for randomization to one further cycle of
either high- or conventional-dose therapy using cyclophosphamide, etoposide, and
carmustine. 60
Dose-response was proven. Conversion from partial to complete
response occurred in 77% of évaluable patients after high-dose therapy, and in
none after conventional-dose treatment. Disease-free survival was significantly
enhanced, and a trend toward improved survival was observed with high-dose
therapy. However, overall outcomes were poor, and an 18% toxic death rate in the
autoBMT arm led the investigators to conclude that dose-intensive therapy should
not be considered a standard therapy in SCLC. Almost all patients recurred in the
chest, reflecting the fact that chest radiotherapy was not given in this trial.
High rates of relapse in sites of prior tumor involvement may be expected, due
to the greater tumor burden and/or drug-resistant clones in the chest by poorer drug
delivery and/or intratumoral resistance factors such as hypoxia in areas of bulk