Mutual support groups that schedule virtual "meetings" via the Internet. Included are e-mail listserv groups (which distribute posted messages to participants via e-mail), bulletin/message boards (whose postings are restricted to people who register), newsgroups (whose postings are unrestricted and open) and chat groups (which permit real time discussion) that are devoted to providing support for participants around a particular issue. Internet support groups are generally available around the clock; and are convenient for people with limited mobility, serious health issues or transportation problems, who don't have time for face-to-face meetings, or who simply wish to maintain their privacy and remain anonymous. They may be the only option for individuals with rare disorders or other unusual problems who are unlikely to find enough people in their local area to form a support group. Internet support groups may be monitored by professionals, but most are not.

Mutual support groups whose members are people who have specific disabilities, illnesses or other health conditions, their families and friends. The groups meet in-person, by telephone or via the Internet; and provide an opportunity for participants to share information, resources, practical tips for daily living and encouragement about issues related to the disability or health problem.

Any of a broad group of malignant neoplasms which are either carcinomas which have their origin in epithelial tissues or sarcomas which develop from connective tissues and those structures which had their origin in mesodermal tissues (the muscular, skeletal, circulatory, lymphatic and urogenital systems and the linings of body cavities). Cancer is invasive and tends to metastasize to new sites spreading directly into surrounding tissues or through the lymphatic or circulatory systems.

People who identify as part of the gender and sexually expansive community that includes people who are lesbian, gay, bisexual, transgender, two-spirit, queer, pansexual, intersex, asexual, bigender, genderqueer, third gender, pangender, nonbinary, gender nonconforming, agender or allied, or who are in the process of coming out or questioning their sexual orientation or gender identity.