Granulocyte colony stimulating factor (G-CSF) prophylaxis and febrile neutropenia (FN) incidence in patients with solid tumours receiving myelotoxic chemotherapy who are assessed as high risk for FN: impact solid study

Purpose: G-CSF primary prophylaxis is recommended for patients undergoing chemotherapy (CT) who are at overall větší-rovno20% risk of FN. Overall risk combines CT myelotoxicity with patient-related risk factors (eg. age). We evaluated real-world G-CSF prophylaxis and neutropenia-related outcomes in patients receiving CT for solid tumours who were assessed as high větší-rovno20%) risk for FN.
Methods: This prospective observational study was conducted in Europe, Australia and Canada. Adults with breast, ovarian, small-cell or non-small cell lung cancers (SCLC and NSCLC) initiating any CT regimen were eligible, if physicians assessed them to be at větší-rovno20% risk of FN (per EORTC guidelines). G-CSF use was recorded. The primary outcome measure was the incidence of FN in cycles 1-8.
Results: Of the 1370 patients enrolled between 12/2007 and 10/2009, 1347 were analyzed. Most patients had breast cancer (Table). The most common CT agents were taxanes in breast cancer (70%), platinum in NSCLC (79%), platinum+etoposide in SCLC (74%) and platinum+paclitaxel in ovarian cancer (55%). Breast cancer patients were relatively young with early stage disease; they received more G-CSF primary prophylaxis than those with other tumours. FN incidence was highest in the SCLC group. Relative dose intensity was lower in lung and ovarian cancers. Neutropenia was a frequent reason for dose delays in all tumours.
Conclusions: Patient factors seemed to be a key determinant of high FN risk assessment in NSCLC and ovarian cancer, whereas breast cancer patients were undergoing curative CT. Despite patients being deemed high risk for FN, G-CSF primary prophylaxis was relatively infrequent and varied by tumour. Physicians appeared more willing to accept CT dose modifications in lung and ovarian cancers than in breast cancer. Sponsor: Amgen Europe (Clinicaltrials.gov NCT00883181)

n (%) [95% CI]	Breast cancer (N=829)	NSCLC (N=224)	SCLC (N=137)	Ovarian (N=157)
Median age (range), years	52 (18-82)	62 (28-83)	62 (42-81)	62 (25-84)
Age ≥65 years	136 (16%)	96 (43%)	51 (37%)	71 (45%)
Advanced stage*	90 (11%)	126 (56%)	98 (72%)	122 (78%)
Prior CT/RT	41 (5%)	59 (26%)	35 (26%)	34 (22%)
Any G-CSF PP	457 (55%)	45 (20%)	44 (32%)	31 (20%)
Pegfilgrastim PP	393 (47%)	22 (10%)	33 (24%)	24 (15%)
Any reactive G-CSF	197 (24%)	59 (26%)	37 (27%)	44 (28%)
Reactive pegfilgrastim	101 (12%)	16 (7%)	16 (12%)	16 (10%)
No G-CSF	175 (21%)	120 (54%)	56 (41%)	82 (52%)
FN (cycles 1-8)	77 (9%) [7, 11]	18 (8%) [5, 12]	0 (15%) [10, 21]	12 (8%) [4, 13]
RDI ≥85%	714 (86%) [84, 88]	133 (59%) [53, 66]	91 (66%) [58, 74]	109 (69%) [62, 76]

*Breast cancer and NSCLC: stage IV; SCLC: extensive; ovarian: stage III-IV. PP, primary prophylaxis: G-CSF initiated in cycle 1 between days 1-7, or by day 12 if chemotherapy extended beyond day 7. Reactive G-CSF: use of G-CSF other than PP (ie. secondary prophylaxis, treatment). RDI, Relative dose intensity (vs planned). RT, radiotherapy

Disclosure: J. Maenpaa: Member of IMPACT SOLID steering committee. Member of MSD-Schering Plough advisory board on ovarian cancer (Finland); P. Sevelda, M. Smakal, A. Trojan, J. Puertas, F.L.G. Erdkamp and K. Krzemieniecki: Member of IMPACT SOLID steering committee; M. Schwenkglenks: Research funding from Amgen (Europe) GmbH. Member of Amgen advisory boards and IMPACT SOLID steering committee; Z. Szabo: Amgen employee and stock holder; K. Bendall: Amgen employee.