“There’s no way in the world, having read the information below, that I would ever have another microchip implanted in any of my dogs again.”

“In six of the articles, between 0.8% and 10.2% of animals developed malignant tumors around or adjacent to the microchips. In almost all cases, the malignant tumors, were typically sarcomas. Given the preliminary data, it looks to me that there’s definitely a major cause for concern.”

– President – PrinceHaus Rottweilers


Microchip-Cancer Report

“Microchip-Induced Tumors in Laboratory Rodents and Dogs:
A Review of the Literature 1990–2006”

by Katherine Albrecht, Ed.D.
Released November 19, 2007

This report is a definitive review of research showing a causal link between implanted radio-frequency (RFID) microchip transponders and cancer in laboratory rodents and dogs. It was written in part to correct industry misstatements and misinformation circulating about the studies. (See bottom of this page for more.)

“Electronic microchip technology as a means of animal identification may affect animal moribundity and mortality (i.e., illness and death rates), due to the large size and rapid growth of microchip-induced tumors as well as the occurrence of metastases.”
– Elcock, et al., 2001

The report evaluates eleven articles previously published in toxicology and pathology journals. In six of the articles, between 0.8% and 10.2% of laboratory mice and rats developed malignant tumors around or adjacent to the microchips.

Two additional articles reported microchip-related cancer in dogs. See Original Research Articles section below for details.

In almost all cases, the malignant tumors, typically sarcomas, arose at the site of the implants and grew to surround and fully encase the devices. These fast-growing, malignant tumors often led to the death of the afflicted animals. In many cases, the tumors metastasized or spread to other parts of the animals. The implants were unequivocally identified as the cause of the cancers.

The report reviews the relevant research and concludes with a series of recommendations for physicians, policy makers, pet owners, and researchers, including the following:

1. Further microchipping of humans should be immediately discontinued;
2. Implanted patients should be informed in writing of the research findings and offered a procedure for microchip removal.
3. Policy makers should reverse all animal microchipping mandates!



? CASPIAN’s September 9, 2007 Press Release:
“Microchip Implants Cause Fast-Growing, Malignant Tumors in Lab Animals”
? Original AP Article:
“Chip Implants Linked to Animal Tumors,” by Todd Lewan, Associated Press
? French Bulldog is Catalyst for Investigation of Microchip-Cancer Connection:
Spychips blog entry by Liz McIntyre explains how the research first came to light


Recent Industry Misstatements about Implant-Cancer Research

“The majority of tumors [in the 1997 Tillmann study] were benign fibrosarcomas…”
– Destron Fearing, makers of the HomeAgain pet implant
Source: “Tissue Reactions to Microchip Implantation in Laboratory Animals
and Pets,” page 2, column 2, paragraph 2.

There is no such thing as a “benign fibrosarcoma.” All of the tumors found in the 1997 Tillmann study were malignant cancers. A fibrosarcoma is a type of sarcoma, a malignant tumor of soft tissue that connects, supports or surrounds other structures and organs of the body. Dr. Timothy Jennings, an expert on implant-induced cancers in humans, said he was “not aware of any nosology incorporating an entity of ‘benign fibrosarcoma'” and agreed that “any tumor classified as sarcoma should be viewed as malignant.”

Time Magazine writes: “In an exclusive interview with TIME, [Scott] Silverman [VeriChip CEO] provided [one of the studies] mentioned in the AP article, which showed that less than 1% of 4,279 chipped mice developed tumors “clearly due to the implanted microchips” but were otherwise healthy, and that “no clinical symptoms except the nodule on their backs were shown.”
– Time Magazine, “Are Microchip Tags Safe?” by Siobhan Morrissey
October 18, 2007. Online at:

The 1997 Tillmann study, to which this passage refers, reported that laboratory mice developed malignant cancers around the microchips that involved “extensive local invasion of the surrounding tissues” and “zones of necrosis and high mitotic activity.” (p. 198) These mice can hardly be referred to as “healthy.”

Time Magazine goes on to say, “The second study, conducted in France in 2006, two years after VeriChip’s FDA application was approved, found that while 4% of the 1,260 mice in the study developed tumors, none of them were malignant.”

The 2006 Le Calvez study, to which this passage refers, found that 4% of mice developed tumors surrounding or adjacent to the microchip implants. All tumors found were classified as sarcomas– a malignant form of cancer. Not only were the tumors malignant, but the often infiltrated nearby muscle tissue, and several metastasized (spread) to the lungs, liver, stomach, or pancreas. Even more disturbingly, many of the implants migrated from the original implantation site on the backs of the mice to cause cancer at other locations in the body. Nineteen percent of the cancers found involved microchips that had migrated from the back to the limbs, abdomen, or head of the mice.

Time Magazine also writes: “As for the third study, Silverman says it was conducted in mice specifically bred to produce tumors, and was therefore omitted from the sheaf of studies included in the FDA application.”

This statement was referring to genetically modified mice used in the 1999 Blanchard study. The p53+/- mouse is genetically modified to have an increased susceptibility to cancer only when exposed to genotoxins, or substances that damage genetic material. It is not known to develop spontaneous tumors in the absence of genotoxins within the first six months of life, when the microchip-induced tumors in this study arose.

The high rate of cancer development in these mice (10.2%) in just six months suggests that implanted microchips may have genotoxic attributes or give rise to the production of genotoxins in the host. The researchers stated that, “the presence of the foreign body [microchip implant] may elicit tissue reactions capable of generating genotoxic byproducts.” This raises a serious red flag about the microchip. The data from this study should have been carefully considered by the FDA during its evaluation of the microchip. It was inappropriate and negligent to omit this information from the FDA application.