In ES-SCLC, Oncologists Often Get Ahead of Formal Risk Categories to Prevent Febrile Neutropenia

Extensive-stage small cell lung cancer (ES-SCLC) is treated almost exclusively with myelosuppressive platinum/etoposide-based chemotherapy, and the disease's pace leaves little room to delay treatment while supportive care catches up. A survey of 301 patients with breast, colorectal, and lung cancers found that 88% felt chemotherapy-induced myelosuppression (CIM) worsened their quality of life, and a retrospective study of more than 3,000 patients with ES-SCLC in the community setting found that 19% were hospitalized within the first 21 days of chemotherapy.¹ For oncologists managing this population, the question is rarely whether to intervene, but how early.

In a Case-Based Roundtable event for oncologists in the Los Angeles area, Sudarsan Kollimuttathuillam, MD, an assistant clinical professor in the Department of Medical Oncology & Therapeutics Research at City of Hope, walked participants through a patient who developed severe febrile neutropenia despite an intermediate-risk classification, using the case to frame a broader discussion of growth factor use, the CDK4/6 inhibitor trilaciclib (Cosela), and the access barriers shaping day-to-day supportive care decisions.

CASE SUMMARY

• A 51-year-old woman presented to the emergency department with coughing, chest pain, and dyspnea.
• Past medical history: thyroidectomy 5 years ago due to thyroid papillary carcinoma (T2N0M0), with subsequent long-term maintenance therapy with levothyroxine, follow-up examinations during this period revealed no particular abnormalities; otherwise healthy
• 20 pack-year history of smoking
• Physical examination: thyroid deficiency, otherwise unremarkable
• Chest CT shows 1.5 cm × 1 cm mass on the right pleural side, associated with pleural thickening and adhesion, and scattered satellite lesions; a minimal right pleural effusion; several mediastinal lymph nodes (largest measuring 1 cm × 1.8 cm; pericardial effusion); no evident anomalies in the left thoracic cavity
• Fine-needle aspiration biopsy of the tumor confirms small cell lung cancer
• Imaging shows no signs of distant metastasis
• Diagnosis: ES-SCLC (right pleura, pericardium involvement)
• ECOG performance status: 1
• Carboplatin/etoposide/atezolizumab (Tecentriq) is initiated.

Platinum/etoposide regimens for ES-SCLC fall into an intermediate-risk category for febrile neutropenia, carrying a 10% to 20% risk that, per ASCO, European Organisation for Research and Treatment of Cancer, and NCCN guidance, warrants primary prophylactic granulocyte colony-stimulating factor (G-CSF) only with at least 1 additional risk factor, such as age over 65, frailty, poor nutritional status, bone marrow involvement, organ dysfunction, or comorbidities including heart failure or chronic obstructive pulmonary disease.^2,3 At 51 years old with none of those factors, this patient would not automatically have qualified. Two weeks after her first cycle, she called reporting chest pain, cough, and fever; workup confirmed febrile neutropenia, with an absolute neutrophil count of 100, alongside sepsis and pneumonia.

The case exposed a gap between guideline categories and clinic-floor practice, with several participants saying they push for primary G-CSF prophylaxis more often than an intermediate-risk classification alone would require. "It's a very myelosuppressive first-line regimen, so I'm very proactive about trying to prevent it," said Anthony Lam, MD, who dose reduces after a first cycle if grade 4 neutropenia develops despite growth factor support. Robert Hsu, MD, noted that hematologic toxicity also complicates trial referral, since many frontline studies require the first cycle of chemotherapy to start inpatient and not every protocol accommodates that. Access, not clinical appetite, emerged as the recurring obstacle: Arati Chand, MD, said reimbursement for branded G-CSF often falls short of acquisition cost, pushing her toward biosimilars that offer similar efficacy for less.

Kollimuttathuillam reviewed trilaciclib, an intravenous CDK4/6 inhibitor that transiently arrests hematopoietic stem and progenitor cells in G1 phase before chemotherapy, protecting neutrophil, erythrocyte, and platelet lineages without shielding the CDK4/6-independent tumor cells of ES-SCLC, an option both NCCN and ASCO guidelines endorse.^4-6 Pooled data from 3 randomized phase 2 trials, G1T28-05 (NCT03041311), G1T28-02 (NCT02499770), and G1T28-03 (NCT02514447),⁷ showed grade 3/4 neutropenia in 32% of patients receiving trilaciclib vs 69% with placebo, and febrile neutropenia in 3% vs 9%. Hospitalizations for CIM or sepsis fell from 13.6% to 4.1% (P =.0088), dose reductions dropped from roughly a quarter of patients to single digits, and treatment delays fell from 58.5% to 34.6%, without compromising antitumor efficacy (progression-free survival HR, 0.80; 95% CI, 0.61-1.06; overall survival HR, 1.00; 95% CI, 0.75-1.35).

Despite that data, only 3 of 14 polled attendees had used trilaciclib before the event. "I've never used this drug, but we obviously have limited time, and we all want what's best for our patients," Lam said, describing a plan to reserve it for older or frailer patients while trying growth factor support alone first in younger ones. Kollimuttathuillam argued the case is more straightforward from the patient's chair than the prior-authorization queue: "If I told them less neutropenia, less infection, less hospitalization, less transfusions, that's a sell," he said.

By the end of the case, 79% of attendees said they were likely to change their approach to febrile neutropenia prophylaxis for a similar patient, evidence that unfamiliarity, not the underlying data, remains the larger barrier to broader trilaciclib use in ES-SCLC.

REFERENCES

1. Hart L, Ogbonnaya A, Boykin K, et al. Burden of chemotherapy-induced myelosuppression among patients with extensive-stage small cell lung cancer: A retrospective study from community oncology practices. Cancer Med. 2023 Apr;12(8):10020-10030. doi: 10.1002/cam4.5738

2. Blayney DW, Schwartzberg L. Chemotherapy-induced neutropenia and emerging agents for prevention and treatment: A review. Cancer Treat Rev. 2022 Sep;109:102427. doi: 10.1016/j.ctrv.2022.102427.

3. Baden LR, Swaminathan S, Almyroudis NG, et al. Prevention and Treatment of Cancer-Related Infections, Version 3.2024, NCCN Clinical Practice Guidelines in Oncology. J Natl Compr Canc Netw. 2024 Nov;22(9):617-644. doi: 10.6004/jnccn.2024.0056

4. Hematopoietic Growth Factors version 3.2026. NCCN Guidelines. Accessed August 18, 2026. https://tinyurl.com/388ausmz

5. Ganti AKP, Loo BW Jr, Badiyan S, et al. NCCN Guidelines® Insights: Small Cell Lung Cancer, Version 2.2026. J Natl Compr Canc Netw. 2026 Jan;24(1):e260002. doi: 10.6004/jnccn.2026.0002.

6. Khurshid H, Ismaila N, Bian J, et al. Systemic Therapy for Small-Cell Lung Cancer: ASCO-Ontario Health (Cancer Care Ontario) Guideline. J Clin Oncol. 2023 Dec 10;41(35):5448-5472. doi: 10.1200/JCO.23.01435.

7. Weiss J, Goldschmidt J, Andric Z, et al. Effects of Trilaciclib on Chemotherapy-Induced Myelosuppression and Patient-Reported Outcomes in Patients with Extensive-Stage Small Cell Lung Cancer: Pooled Results from Three Phase II Randomized, Double-Blind, Placebo-Controlled Studies. Clin Lung Cancer. 2021 Sep;22(5):449-460. doi: 10.1016/j.cllc.2021.03.010