Higher incidence of pegfilgrastim-induced bone pain in younger patients receiving myelosuppressive chemotherapy: a real-world experience.

BACKGROUND: Pegfilgrastim is widely used for the prevention of febrile neutropenia (FN) in patients receiving myelosuppressive chemotherapy for various types of cancer. However, pegfilgrastim-induced bone pain (PIBP) is a relevant adverse event occurring during cancer treatment. Thus, we aimed to determine the risk factors for PIBP in real-world clinical practice. MAIN BODY: We retrospectively collected the clinical records of patients who received pegfilgrastim to support myelosuppressive chemotherapy with at least a 10% risk of FN between 2015 and 2018 at our center. Patients received pegfilgrastim 3.6 mg between days 2 and 7 after chemotherapy administration (day 1) for primary or secondary prophylaxis against FN. All adverse events were recorded according to the Common Terminology Criteria for Adverse Events. Patients who experienced intermittent bone pain in the back, femur, or other anatomic sites after the pegfilgrastim administration were considered to have PIBP. To evaluate the relationship between PIBP incidence and patient characteristics, we performed univariate and multivariate logistic regression analyses to calculate the odds ratios (ORs) of possible risk factors for PIBP. We analyzed the data of 305 patients (median age: 63 years), who underwent 1220 chemotherapy cycles with pegfilgrastim per cycle. Univariate analysis revealed that female sex (vs. male sex), younger age (< 55 years vs. ≥ 55 years), and solid cancers (vs. hematologic cancers) had significantly higher ORs (p < 0.05). However, only younger age (< 55 years) was an independent risk factor for PIBP on multivariate analysis (OR 3.62, 95% confidence interval 1.51-8.69, p = 0.004). CONCLUSIONS: Younger age (< 55 years) was significantly associated with a higher risk of PIBP among patients receiving chemotherapy with a ≥ 10% risk of FN. Therefore, oncologists should meticulously formulate management plan for PIBP in younger patients after administering pegfilgrastim.

Useful markers for detecting minimal residual disease in cases of neuroblastoma.

Neuroblastoma (NB), which is a malignant tumor of young children derived from neural crest cells that occurs in children, exhibits a wide range of clinical behaviors, from spontaneous regression to rapid progression. Advanced NB patients have a poor prognosis, and recently, autologous bone marrow transplantation (BMT) and autologous peripheral blood stem cell transplantation (PBSCT) have been attempted to improve the prognosis of these patients. In this study, we attempted to detect the expression of tyrosine hydroxylase (TH), neuroendocrine protein gene product (PGP) 9.5, ELAVL-4 and GD2 synthetase (GALGT), all of which are highly expressed in NBs, by the reverse transcription-polymerase chain reaction (RT-PCR) technique in order to detect minimal residual disease (MRD) in the bone marrow (BM) and peripheral blood (PB). Analysis of various tumor cell lines (Ewing's sarcoma, hepatoma, leukemias, and breast cancer cell lines in addition to NBs), and human normal samples (BM and PB cells) revealed that TH was the most specific marker for the detection of NB. On the other hand, PGP9.5 was the most sensitive marker, and was detected even when there was only one positive cell per 10(7) negative cells. We concluded that TH is a better marker before the diagnosis of NB while PGP9.5 is a better marker to detect MRD after the diagnosis. Here, we describe our results on useful markers to detect MRD in patients with NB.

Analyses of novel prognostic factors in neuroblastoma patients.

Neuroblastoma (NB) is the most common malignant solid tumor in childhood. There are well-recognized prognostic factors in NB such as age at diagnosis, organ of origin, stages, MYCN gene amplification, and expression of H-ras, trkA and survivin. Moreover, we investigated the expression of vascular endothelial growth factor (VEGF), tyrosine hydroxylase (TH), p53, stem cell factor (SCF) and c-kit of its receptor with quantitative real-time polymerase chain reaction (PCR) in 22 NBs and 4 other tumors (one malignant lymphoma, one malignant teratoma, and 2 rhabdomyosarcomas) samples. The correlation between patients' prognoses and the expression of TH or c-kit was newly recognized, particularly the good prognosis in patients in whom c-kit highly expressed and the poor prognosis contrarily associated with low or no expression, although the SCF of its ligand had no relationship with patient prognosis. It is possible that tumors without c-kit expression can not react with SCF (via the autocrine or paracrine system) and remain immature. It may be that this is a new critical clinical event in NB patients.

Significance of survivin mRNA expression in prognosis of neuroblastoma.

Neuroblastoma (NB) is the most common malignant solid tumor in childhood, and among all childhood malignancies is second in prevalence only to leukemia. In NB we need to both make an accurate diagnosis and rapidly analyze the expression of genetic prognostic factors such as MYCN, H-ras, and trkA. Moreover, it has recently become important to analyze the expression of survivin mRNA, a member of the inhibitor of apoptosis protein family. Expression of the survivin gene is related to tumorigenesis and inhibition of apoptosis in some malignant tumors. We investigated its expression by reverse transcription-polymerase chain reaction (RT-PCR) in NB cell lines (SK-N-SH, NB-39, and IMR-32), two normal blood cell samples, and 13 clinical NB tumor samples. All three NB cell lines had high levels of mRNA expression for this gene, but normal blood cells had no expression. We detected expression of survivin mRNA in 7 of the 13 NB tumor samples (54%). Two NB patients were in stage I disease, 6 in stage II, and 5 in stage IV(A). Quantitative analysis by RT-PCR revealed that the ratio between survivin mRNA and human glyceraldehyde-3-phosphate dehydrogenase (h-GAPDH) mRNA was very low in stages I and II (0-0.017). In contrast, in advanced NBs (stage IV(A)) the ratio was much higher (0-0.050). The prognoses of the three patients in the advanced stage who had high ratios of expression were poor. A high level of expression of survivin mRNA indicates a high grade of malignancy, high likelihood of recurrence, and poor prognosis.