use of PET in clinical research, clinical trials, and drug discovery
use of PET/CT in assessing response to therapy
In some cases, such as Hodgkins lymphoma, quantitative PET/CT imaging may not actually be needed, as success can be defined by the complete absence of tracer uptake in the PET image following a course of standardized therapy
The utilization of PET/CT to assess response to therapy is increasing in the US related, in part, to the creation and subsequent favorable results of the National Oncologic PET Registry (NOPR)
Changes in size as a result of therapy may take many months to develop and any opportunity to make early decisions about therapy success or failure is often unduly delayed or lost altogether
measures of changes in metabolic activity via FDG PET/CT can provide an alternate approach to assess response to therapy -- often very early in the course of treatment
Current recommendations are that tumor SUVs should be reported
The true tracer uptake in a patient is composed of two components: the first being the amount of tracer uptake (e.g. FDG) associated with the disease status (the signal of interest), which can be modified by the biophysiological status of the patient. One of the more important patient parameters is the blood glucose level, which has been shown to inversely-linearly affect SUVs
A prospective study by Crippa et al.30 in eight patients showed that as blood glucose levels were increased from 92.4 ±10.2 to 158 ± 13.8 mg/100 ml by glucose loading, the average SUV of 20 liver metastases decreased from 9.4 ± 5.7 to 4.3 ± 8.3
chemotherapy can result in impaired renal function, significantly reducing the clearance of plasma FDG through the kidney and thus increasing tumor SUV relative to an initial PET scan
The second component of the true tracer uptake is biological variability
The biological variability has been estimated in several test-retest studies7,32–35 at approximately 10% for scans repeated within a few days
Studies have shown that the production of nagalase has a mutual relationship with Gc-MAF level and immunosuppression
It has been demonstrated that serum levels of nagalase are good prognosticators of some types of cancer
The nagalase level in serum correlates with tumor burden and it has been shown that Gc-MAF therapy progresses, nagalase activity decreases
It has been shown that Gc-MAF can inhibit the angiogenesis induced by pro-inflammatory prostaglandin E1
The effect of Gc-MAF on chemotaxis or activation of tumoricidal macrophages is likely the main mechanism against angiogenesis.
Administration of Gc-MAF stimulates immune-cell progenitors for extensive mitogenesis, activates macrophages and produces antibodies. “This indicates that Gc-MAF is a powerful adjuvant for immunization.”
Cancer cell lines do not develop into tumor genes in mouse models after Gc-MAF-primed immunization (29-31) and the effect of Gc-MAF has been approved for macrophage stimulation for angiogenesis, proliferation, migration and metastatic inhibition on tumors induced by MCF-7 human breast cancer cell line
The protocol included: "a high dose of second-generation Gc-MAF (0.5 ml) administered twice a week intramuscularly for a total of 21 injections.”
Yamamoto et al. showed that the administration of Gc-MAF to 16 patients with prostate cancer led to improvements in all patients without recurrence
Inui et al. reported that a 74-year-old man diagnosed with prostate cancer with multiple bone metastases was in complete remission nine months after initiation of GcMAF therapy simultaneously with hyper T/NK cell, high-dose vitamin C and alpha lipoic acid therapy
It has also been approved for non-neoplastic diseases such as autism (41), multiple sclerosis (42, 43), chronic fatigue syndrome (CFS) (40), juvenile osteoporosis (44) and systemic lupus erythematous (45).
Gc-MAF has been verified for use in colon, thyroid (38), lung (39), liver, thymus (36), pancreatic (40), bladder and ovarian cancer and tongue squamous carcinoma
Prostate, breast, colon, liver, stomach, lung (including mesothelioma), kidney, bladder, uterus, ovarian, head/neck and brain cancers, fibrosarcomas and melanomas are the types of cancer tested thus far
weekly administration of 100 ng Gc-MAF to cancer at different stages and types showed curative effects at different follow-up times
this treatment has been suggested for non-anemic patients
Studies have shown that weekly administration of 100 ng Gc-MAF to cancer patients had curative effects on a variety of cancers
Because the half-life of the activated macrophages is approximately one week, it must be administered weekly
In vivo weekly intramuscular administration of Gc-MAF (100 ng) for 16-22 weeks was used to treat patients with breast cancer
individuals harboring different VDR genotypes had different responses to Gc-MAF and that some genotypes were more responsive than others
Administration of Gc-MAF for cancer patients exclusively activates macrophages as an important cell in adaptive immunity
Gc-MAF supports humoral immunity by producing, developing and releasing large quantities of antibodies against cancer. Clinical evidence from a human model of breast cancer patients supports this hypothesis
There is also evidence that confirms the tumoricidal role of Gc-MAF via Fc-receptor mediation
It is likely that the best therapeutic responses will be observed when the nutritional and inflammatory aspects are taken together with stimulation of the immune system
it should be noted that no harmful side effects of Gc-MAF treatment have been reported, even when it was successfully administered to autistic children
The natural activation mechanism of macrophages by Gc-MAF is so natural and it should not have any side effects on humans or animal models even in cell culture
Besides the Gc-MAF efficacy on macrophage activity, it can be a potential anti-angiogenic agent (28) and an inhibitor of the migration of cancerous cells in the absence of macrophages (47).
Activating or modifying natural killer cells, dendritic cells, DC, CTL, INF and IL-2 have all been recommended for cancer immunotherapy
It has been reported that nagalase cannot deglycosylate Gc-MAF as it has specificity for Gc globulin alone
inflammation-derived macrophage activation with the participation of B and T lymphocytes is the main mechanism
macrophages highly-activated by the addition of Gc-MAF can show tumoricidal activity
Previous clinical investigations have confirmed the efficacy of Gc-MAF. In addition to activating existing macrophages, Gc-MAF is a potent mitogenic factor that can stimulate the myeloid progenitor cells to increase systemic macrophage cell counts by 40-fold in four days