Adjuvant therapy
adjuvant therapy
MedspeakAny therapy that increases a primary treatment’s efficacy; auxiliary therapy.
Oncology
A treatment used after failure of chemotherapy, radiotherapy or hormones as a primary treatment of a tumour to prevent metastases, or for residual malignancy after excision; AT is used after one or more of the conventional therapeutic arms has failed.
Adjuvant therapies
Breast cancer
Various combinations of cyclophosphamide, doxorubicin, docetaxel, 5-FU, MTX, paclitaxel and others have been used with some reduction in metastases.
Colorectal cancer
Adjuvant chemotherapy for colorectal cancer has not been highly successful; 5-FU might reduce micrometastases.
Melanoma
While interferon alpha 2b is FDA-approved, and various chemotherapeutics have been used against advanced melanoma, responses have been minimal and short-lived.
Adjuvant therapy for breast cancer
Recommended after breast-conserving surgery
• If Nottingham prognostic index (NPI) is > 3.0, ER +ve; possible chemotherapy if NPI > 4.4;
• ER -ve, recommend chemotherapy.
Not recommended if Nottingham prognostic index is < 3.0
ER+ hormonal therapy; ER- no hormonal therapy, but if NPI > 5.4 chemotherapy for > age 50, or > 4.4 if < age 50.
Adjuvant Therapy
Therapy that enhances a primary therapy; the addition of one or more therapeutic modalities to a primary or initial management strategy to improve survival, usually in the context of cancer care. For example, the first-line treatment for melanoma, colorectal and breast cancer is surgical, assuming that they are in early stages (ideally under stage 3), with radiotherapy and various forms of local or systemic therapy (chemotherapy, regional hyperthermia with chemotherapy, hormonal manipulation, immunotherapy—BCG, IL-2-stimulated lymphokine-activated killer cells, IFN-alpha and biological response modifiers) serving as adjuvants.Adjuvant therapy is also defined as a treatment which is used:
• After failure of the primary therapeutic modality (chemotherapy, radiotherapy, immunotherapy hormones);
• Instead of the primary modality, based on unique tumour characteristics or patient preferences;
• To prevent metastases; or
• For residual malignancy after excision.
Fives “rules” of adjuvant therapy were published in the JAMA in 1990 (264:1444), and are still relevant:
(1) There may be occult, viable tumour cells in circulation—intravascular, intralymphatic, or intraperitoneal and/or established, microscopic foci of tumour cells locally, at distant sites, or both.
(2) Therapy is most effective when tumour burden is minimal and cell kinetics are optimal.
(3) Agents with proven effectiveness against the tumour must be used.
(4) Cytotoxic therapy shows a dose-response relationship and therefore must be administered in maximally tolerated doses, and duration of therapy must be sufficient to eradicate all tumour cells.
(5) The risk-to-benefit ratio for therapy must be favourable for individuals who may remain asymptomatic for their natural life expectancy after tumour resection.
Examples, Adjuvant therapies
Breast cancer Various combinations of cyclophosphamide, doxorubicin, docetaxel, 5-FU, MTX, paclitaxel and other have been used with some reduction in metastases.
Colorectal cancer Aduvant chemotherapy for colorectal cancer has not been hugely successful; 5-FU might reduce micrometastases.
Melanoma While interferon alpha 2b is FDA-approved and various chemotherapeutics have been used for advanced melanoma, responses have been minimal and short-lived.