Cancer therapy complications and supportive care: Case

This boy presents three overlapping toxicities of the high emetogenic induction regimen that the supportive care is built to manage. The breakthrough vomiting despite the ondansetron alone signals the antiemetic combination that is underpowered for the risk, because the cyclophosphamide above one gram per square metre is a high emetogenic agent. The extensive oral ulceration that stops the eating and the drinking is the severe mucositis of the WHO grade 3 or 4. The single temperature of 38.7 degrees with the absolute neutrophil count of 120 is the febrile neutropenia that needs the antibiotic within the hour. The heart rate of 140 and the daunorubicin exposure frame the cardiac risk that the dexrazoxane protects across the treatment. [1][9]

Interpretation of the three problems

The three problems are the breakthrough chemotherapy-induced nausea and vomiting, the severe oral mucositis, and the febrile neutropenia, and each has a specific interpretation. The cyclophosphamide above one gram per square metre is a high emetogenic agent, and the vomiting despite the ondansetron alone is the predictable consequence of the underpowered prophylaxis, because the high risk demands the three-drug combination. The extensive ulceration of the tongue and the buccal mucosa with the bleeding and the refusal of all food and fluid meets the WHO grade 3, the ulcers with the liquid diet only, and the grade 4 if the oral intake is impossible. [1][4]

The single temperature of 38.7 degrees with the absolute neutrophil count of 120 is the febrile neutropenia, because the threshold is the single oral temperature at or above 38.3 degrees with the count under 500. The heart rate of 140 with the capillary refill of two seconds and the normal blood pressure places the boy in the compensated rather than the decompensated state, but the neutropenic sepsis can deteriorate rapidly, and the well appearance is deceptive. The daunorubicin in the regimen frames the anthracycline exposure that the dexrazoxane must protect across the induction and the maintenance, and the cumulative dose is tracked from the start. [9]

Management: the fever first

The immediate priority is the febrile neutropenia, because the delay kills the neutropenic child. The blood cultures are taken from each lumen of the central line plus a peripheral sample when feasible, and the empiric antipseudomonal beta-lactam such as cefepime, piperacillin with tazobactam, or meropenem is given within one hour. The heart rate of 140 and the count of 120 warrant the close monitoring for the haemodynamic deterioration, and the vancomycin is added if the line infection is suspected or the boy becomes unstable. The resuscitation is prepared with the isotonic fluid and the escalation to the intensive care, because the neutropenic sepsis can progress to the shock within the hours. [9]

The work-up adds the full blood count, the electrolytes, the C-reactive protein, and the lactate, and the urinalysis and the chest radiograph. The mouth swab and the blood culture are taken for the secondary Candida or herpes that complicate the broken mucosal barrier, because the oral bacteria seed the bloodstream when the child is neutropenic. The boy is admitted to the ward or the high-dependency unit for the intravenous antibiotic and the monitoring, and the reassessment at the 48 to 72 hours determines the low-risk step-down. [4][9]

Management: the vomiting and the mouth

The antiemetic regimen is escalated to the three-drug combination for the high emetogenic risk. The ondansetron at 0.15 mg per kg per dose to a maximum of 8 mg per dose is continued as the backbone, and the dexamethasone and the NK1 antagonist aprepitant are added, with the aprepitant continued through the days two and three for the delayed nausea. The mediators of the vomiting are the 5-hydroxytryptamine and the substance P, and the two receptors, the 5-HT3 and the neurokinin-1, are the targets of the two main classes of the antiemetic. The matched prophylaxis is planned for the next cycle to prevent the breakthrough that the single agent allowed. [1]

The mucositis is managed by the grade and the pain. The WHO grade 3 with the refusal of the food and the fluid receives the opioid by the continuous infusion or the patient-controlled analgesia, and the intravenous or the nasogastric nutrition is started early because the oral intake is impossible. The mouth is kept clean with the basic oral care, the Candida and the herpes are treated when the swab confirms them, and the healing is watched for the regeneration of the mucosa over the second week. The prevention for the high-risk cycles rests on the MASCC and ISOO evidence of the cryotherapy, the photobiomodulation, and the palifermin at 60 microg per kg per day for the stem-cell transplant conditioning. [4]

Protecting the heart across the treatment

The daunorubicin in the regimen is the anthracycline that threatens the heart, and the dexrazoxane is the primary cardioprotection. The 2022 harmonisation guideline of de Baat and the International Late Effects of Childhood Cancer Guideline Harmonization Group recommends the dexrazoxane for the child who is expected to receive the anthracycline, given at a ten-to-one ratio with the doxorubicin dose, so that 300 mg per square metre of the dexrazoxane accompanies 30 mg per square metre of the doxorubicin. The dexrazoxane chelates the iron and interrupts the free-radical cascade that scars the cardiomyocyte, and the boy is among the youngest and the most vulnerable, because the child treated under the age of five carries the highest risk of the late heart failure. [6]

The surveillance is the second pillar, with the baseline echocardiogram before the first anthracycline and the serial echocardiogram and the troponin through the treatment. The Chow study of the childhood cancer survivors confirmed that the dexrazoxane preserves the long-term heart function without compromising the cancer control, and the boy enters the survivorship with the periodic echocardiogram through the decades, the cumulative dose capped, and the heart-healthy lifestyle reinforced. The boy who receives the dexrazoxane and the surveillance from the start is the boy who enters the adulthood with the preserved heart, and the supportive care delivered in the childhood is the foundation of the cardiac health of the survivor. [6][9]