The results indicated that the adjuvant therapy given after the initial radical mastectomy "significantly decreased recurrence rate in pre-menopausal women with four or more positive axillary lymph nodes.
"[2] The budding theory of using additional therapies to supplement primary surgery was put into practice by Gianni Bonadonna and his colleagues from the Instituto Tumori in Italy in 1973, where they conducted a randomized trial that demonstrated more favorable survival outcomes that accompanied use of Cyclophosphamide Methotrexate Fluorouracil (CMF) after the initial mastectomy.
If no active cancer cells are present in a tissue extracted from the tumor site after neoadjuvant therapy, physicians classify a case as "pathologic complete response" or "pCR."
While response to therapy has been demonstrated to be a strong predictor of outcome, the medical community has still not reached a consensus in regard to the definition of pCR across various breast cancer subtypes.
Because the treatment is essentially for a risk, rather than for provable disease, it is accepted that a proportion of patients who receive adjuvant therapy will already have been cured by their primary surgery.
From the time of its inception, the use of adjuvant therapy has received scrutiny for its adverse effects on the quality of life of cancer patients.
[13] In such cases, physicians must weigh the cost of recurrence against more immediate consequences and consider factors, like age and relative cardiovascular health of a patient, before prescribing certain types of adjuvant therapy.
[14] For example, breast cancer patients of fertile age oftentimes have to weigh the risks and benefits associated with starting an adjuvant therapy regimen after primary treatment.
[citation needed] However, it has been found a single dose of carboplatin is as effective as EBRT in stage II testicular cancer, with only mild side effects (transient myelosuppressive action vs severe and prolonged myelosuppressive neutropenic illness in normal chemotherapy, and much less vomiting, diarrhea, mucositis, and no alopecia in 90% of cases.
This practice has led scientists to the hypothesis that the recurrence of cancer after surgery and chemo may be due to the rapidly diving cells outpacing the rate of chemotherapy administration.
In 1995 a multicenter study reported improved long-term and disease-free survival in melanoma patients using interferon alpha 2b as an adjuvant therapy.
Thus, later that year the U.S. Food and Drug Administration (FDA) approved interferon alpha 2b for melanoma patients who are currently free of disease, to reduce the risk of recurrence.
Multiple studies have shown that adjuvant radiotherapy improves local recurrence rates in high-risk melanoma patients.
A number of studies are currently underway to determine whether immunomodulatory agents which have proven effective in the metastatic setting are of benefit as adjuvant therapy for patients with resected stage 3 or 4 disease.
[22] Neoadjuvant chemotherapy (NAC) followed by a radical cystectomy (RC) and pelvic lymph node dissection is current standard of care to treat muscle-invasive bladder cancer (MIBC).
Enhanced recovery after surgery protocols have recently improved perioperative care and may make earlier time to AC administration less challenging.
[28] It has been known for at least 30 years that adjuvant chemotherapy increases the relapse-free survival rate for patients with breast cancer[29] In 2001 after a national consensus conference, a US National Institute of Health panel concluded: "Because adjuvant polychemotherapy improves survival, it should be recommended to the majority of women with localized breast cancer regardless of lymph node, menopausal, or hormone receptor status.
"[2] Agents used include: However, ethical concerns have been raised about the magnitude of benefit of this therapy since it involves further treatment of patients without knowing the possibility of relapse.
Commonly used combination chemotherapy regimens used include: Roughly 15% of ovarian cancers are detected at the early stage, at which the 5-year survival rate is 92%.
[33] A Norwegian meta-analysis of 22 randomized studies involving early-stage ovarian cancer revealed the likelihood that 8 out of 10 women treated with cisplatin after the initial surgery were overtreated.
For advanced cervical cancers, further research is needed to determine the efficacy, toxicity and effect on the quality of life of adjuvant chemotherapy.
[35] Since most early-stage endometrial cancer cases are diagnosed early and are typically very curable with surgery, adjuvant therapy is only given after surveillance and histological factors determine that a patient is at high risk for recurrence.
Adjuvant pelvic radiation therapy has received scrutiny for its use in women under 60, as studies have indicated decreased survival and increased risk of second malignancies following treatment.
[39] Patients treated with standard chemotherapy regimens can experience "second malignant neoplasms, cardiovascular disease, neurotoxicity, nephrotoxicity, pulmonary toxicity, hypogonadism, decreased fertility, and psychosocial problems.
"[40] As such to minimize overtreatment and avoid potential long-term toxicity caused by adjuvant therapy, most patients today are treated with active surveillance.
Depending on the agents used, side effects such as chemotherapy-induced peripheral neuropathy, leukoencephalopathy, bladder damage, constipation or diarrhea, hemorrhage, or post-chemotherapy cognitive impairment.
[citation needed] Radiotherapy causes radiation dermatitis and fatigue, and, depending on the area being irradiated, may have other side effects.
Adjuvant hormonal therapy for prostate cancer may cause cardiovascular disease, and other, possibly severe, side effects.