Chemotherapy dosing

If a patient has renal or hepatic impairment or a poor metabolizer genotype, adjust chemotherapy doses if necessary. 

Knowing how to prevent and treat adverse events from chemotherapy is an important aspect of patient care. Unmanaged events may result in excess morbidity and cause delays in chemotherapy administration and reduced chemotherapy doses and contribute to treatment failure. 

Changes in organ function adjust chemotherapy doses as indicated. 

Other studies evaluated the question of whether early delivery of radiation concurrently with chemotherapy was better than late delivery. A study performed by the C ALGB randomized patients to early (d 1, cycle 1), late (d 64, cycle 4), or no radiation therapy. The radiation therapy dose was 50 Gy over 6 wk. Chemotherapy used in this trial was cyclophosphamide, etoposide, and vincristine. The local recurrence rate for the early, late, and no radiation therapy arms was 49%, 68%, and 82%, respectively. The 2-yr progression-free survival rate was 15% for the early schedule arm vs 25% for the late schedule (p = 0.078). The 5-yr survival rate for the early, late, and no radiation therapy arms was 6.6%, 12%, and 3%, respectively (p = 0.007). The poor 5-yr survival rate for the early schedule was felt to be due to the significant decrease in chemotherapy dose needed for the early schedule group (4,49). 

Current data support the use of concurrent over sequential or alternating chemotherapy and radiation therapy. The optimal delivery of concurrent chemoradiation is still under study. Early delivery of radiation therapy may decrease dissemination by killing the chemoresistant tumor cells prior to their distant seeding. Late delivery of radiation therapy possibly reduces toxicities and full chemotherapy doses can be delivered. However, even with increased toxicity, improved survival rates help establish as standard early delivery of concurrent radiation with platinum-based chemotherapy. 

The studies of chemoradiation that have been completed in patients with carcinoma of the cervix provide little specific guidance about the importance of chemotherapy dose and schedule. 

After a meticulous review of the biomedical literature, the panel concluded that routine use of colony-stimulating factors for primary prophylaxis of febrile neutropenia in previously untreated patients is not justified by existing data. There is evidence, however, that colony-stimulation factor administration can decrease the probability of febrile neutropenia in subsequent cycles of chemotherapy after a documented occurrence in an earlier cycle. However, dose reduction after a severe episode, rather than administration of colony-stimulating factors, should be considered as a primary therapeutic option. In the absence of clinical evidence or other compelling reasons to maintain chemotherapy dose intensity, physicians should consider chemotherapy dose reduction... 

Should any adjustment be made to the chemotherapy doses based on Mr AC s laboratory results ... 

B. Dose lorazepam a few hours prior to the next chemotherapy dose. 

Encephalopathy, peripheral neuropathy, cerebellar syndromes, autonomic neuropathy, and cranial nerve toxicity represent the range of neurological complications associated with cancer chemotherapy. Dose, route of administration, age of the patient, hepatic and renal function, prior and/or concomitant use of other neurotoxic drugs, and the concurrent use of cranial or CNS radiotherapy can each influence the incidence rate and severity of neurologic symptoms associated with selected chemotherapy drugs. 

A total of 503 interventions were reported clinical consultations, correction of prescribing eiTors, and patient treatment procedures accounted for approximately two-thirds of the interventions (Table 6). In this study, all clinical interventions were related to chemotherapy-related toxicides or drug-dosing and -administration issues. The 167 documented clinical consultations were related to nausea or vomiting (29.3%), chemotherapy dosing or... 

Piccart MJ, Biganzoh L, Di Leo A. The impact of chemotherapy dose density and dose intensity on breast cancer outcome what have we learned Eur J Cancer 2000 36(Suppl 1) S4-S 10. 

Several smdies have attempted to improve treatment results by increasing chemotherapy dose (i.e., dose-intensity), shortening the interval between chemotherapy cycles (i.e., dose-density), or both. Because of the increased risk of severe neutropenia, these approaches require growth factor support. Although results of these studies have not consistently shown improved survival, encouraging results from several recently published smdies suggest that these approaches be evaluated in future randomized trials. ... 

Geh JI, Bond SJ, Bentzen SM, et al (2006) Systemic overview of preoperative (neoadjuvant) chemoradiotherapy in patients with oesophageal cancer evidence of a radiation and chemotherapy dose response. Radiother Oncol 78 236-244 Gerard J, Romestaing P, Bonnetain F, et al (2005) Preoperative chemoradiotherapy (CT-RT) improves local control in T3-4 rectal cancers results of the FFCD 9203 randomized trial (abstract). Int J Radial Oncol Biol Phys 63(suppl 1) S2-S3... 

Steel GG, Peckham MJ (1979) Exploitable mechanisms in combined radiotherapy-chemotherapy the concept of additivity. Int J Radiat Oncol Biol Phys 5 85-91 Stewart DJ, Chiritescu G, Dahrouge S, et al. (2007) Chemotherapy dose-response relationships in non-small cell lung cancer and implied resistance mechanisms. Cancer Treat Rev 33 101-137... 

Fong Y et al. (1999) Clinical score for predicting recurrence after hepatic resection for metastatic colorectal cancer analysis of 1001 consecutive cases. Ann Surg 230 309-318 Frei El, Antman K (1993) Combination chemotherapy dose and schedule. In Holland JF, Frei III E, Bast Jr RC, Morton DL, Weichselbaum RR (eds) Cancer Medicine, 3rd edn. Lea and Febiger, Philadelphia, pp 631-639 Friedman MA, Carter SK (1972) The therapy of osteogenic sarcoma current status and thoughts for the future. J Surg Oncol 4 482-510... 

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