Integral dose (ID)

This is the total energy absorbed/deposited by ionizing radiation, within a body/in the treated volume (in J = kg × Gy) [1]. It is «one way of comparing dose distributions for different-quality beams. (...) If a mass of tissue receives a uniform dose, then the integral dose is simply the product of mass and dose. However, in practice, the absorbed dose in the tissue is nonuniform so rather complex mathematical formulas are required to calculate it. For a single beam of x- or γ radiation, Mayneord formulated the following expression:

Σ=1.44 D₀  A d_1⁄2 (1 - e^(0.693 d/d_1⁄2))  (1 + (2.88 d_1⁄2)/SSD)

where ∑ is the integral dose, D₀ is the peak dose along the central axis, A is the geometric area of the field, d is the total thickness of the patient in the path of the beam, d_1⁄2 is the half-value depth or the depth of 50% depth dose, and SSD is the source to surface distance. The term (1 + (2.88 d_1⁄2)/SSD) is a correction for the geometric divergence of the beam. Because the integral dose is basically the product of mass and dose, its unit is the kilogram-gray or simply joule (since 1 Gy = 1 J/kg). (...) It is generally believed that the probability of damage to normal tissue increases with the increase in the integral dose, (...) [2].»

Bibliographic references:

[1] Beyzadeoglu, M., Ozyigit, G. and Ebruli, C., 2010. Basic radiation oncology. 1st ed. Berlin: Springer, p.23.

[2] Khan, F. and Gibbons, J., 2016. Khan's the physics of radiation therapy. 5th ed. Philadelphia: Wolters Kluwer, p.181.

IASLC (International Association for the Study of Lung Cancer)

International Association for the Study of Lung Cancer

Bibliographic reference: International Association for the Study of Lung Cancer | IASLC [Internet]. Iaslc.org. [cited 20 April 2020]. Available from: https://www.iaslc.org/.

Image-guided radiation therapy (IGRT)

IGRT is the «radiotherapy that uses image guidance procedures for target localization before and during treatment. These procedures use imaging technology to identify and correct problems arising from inter- and intrafractional variations in patient setup and anatomy, including shapes and volumes of the treatment target(s), organs at risk, and surrounding normal tissues. The goal of IGRT is to reduce the geometrical uncertainty in a given treatment fraction by evaluating the patient geometry at the time of treatment and either altering the patient position or adapting the treatment plan with respect to anatomical changes that occur during the radiotherapy treatment course.»

Bibliographic reference: Xiao Y. Image-Guided Radiation Therapy (IGRT): kV Imaging. In: Brady LW, Yaeger TE (Eds), Encyclopedia of Radiation Oncology. Berlin, Heidelberg: Springer, Berlin, Heidelberg; 2013. p. 343.

Intraepithelial neoplasia (IEN)

It «is the development of a benign neoplasia or high-grade dysplasia in an epithelium. The exact dividing line between dysplasia and neoplasia has been very difficult to draw throughout the era of medical science. It varies between persons. (...). It is not cancer, but it is associated with higher risk for developing cancer in future. It is thus sometimes a precancerous condition [1].» «The changes in the cells may be low grade or high grade, (...) [2].»  «Dysplasia can be low-grade or high-grade. High-grade dysplasia may also be referred to as carcinoma in situ [3].» It is «an in situ carcinoma confined to an epithelium that may superficially penetrate adnexal glands, measuring < either 3 mm or 5 mm depending on the criteria used. Abnormal cell growth that is found within epithelial cells but has not yet spread to neighboring, underlying, or distant tissues [4].» It is «a proliferation of malignant-appearing cells without evidence of invasion through the epithelial basement membrane [5].»

Evolution of cancer:

Source: Oncology (Cancer) - Health Facts [Internet]. Ndhealthfacts.org. 2017 [cited 2019 Jul 7]. Available from: http://www.ndhealthfacts.org/wiki/Oncology_%28Cancer%29.

Vulval intraepithelial neoplasia (VIN):

Source: Vulval intraepithelial neoplasia (VIN) | Vulval cancer | Cancer Research UK [Internet]. Cancerresearchuk.org. 2019 [cited 2019 Jul 7]. Available from: https://www.cancerresearchuk.org/about-cancer/vulval-cancer/stages-types-grades/vulval-intraepithelial-neoplasia.

Bibliographic references:

[1] Intraepithelial neoplasia [Internet]. En.wikipedia.org. 2015 [cited 2019 Jul 7]. Available from: https://en.wikipedia.org/wiki/Intraepithelial_neoplasia.

[2] NCI Dictionary of Cancer Terms [Internet]. National Cancer Institute. [cited 2019 Jul 7]. Available from: https://www.cancer.gov/publications/dictionaries/cancer-terms/def/intraepithelial-neoplasia.
[3] Carcinoma in situ [Internet]. En.wikipedia.org. 2019 [cited 2019 Jul 7]. Available from: https://en.wikipedia.org/wiki/Carcinoma_in_situ.

[4] Intraepithelial neoplasia [Internet]. TheFreeDictionary.com. [cited 2019 Jul 7]. Available from: https://medical-dictionary.thefreedictionary.com/intraepithelial+neoplasia.

[5] Wazer DE. In Situ Carcinoma. In: Brady L. Encyclopedia of radiation oncology. Berlin: Springer; 2013. p. 373.

Immunotherapy

It uses «the body’s immune system to fight cancer cells by stimulating the immune system. (...). Immunotherapy may be used by itself or with other types of treatment. The main types of immunotherapy being used to treat cancer include: monoclonal antibodies, immune checkpoint inhibitors, and cancer vaccines [1].»
It is «a type of therapy that uses substances to stimulate or suppress the immune system to help the body fight cancer, infection, and other diseases. Some types of immunotherapy only target certain cells of the immune system. Others affect the immune system in a general way. Types of immunotherapy include cytokines, vaccines, bacillus Calmette-Guerin (BCG), and some monoclonal antibodies [2].»

It is a type of targeted therapy.

Bibliographic references: 

[1] Cancer-champions.com. (n.d.). Chemotherapy, Immunotherapy, Targeted Therapy. What's the difference? | Cancer-Champions health-care consulting. [online] Available at: https://cancer-champions.com/chemotherapy-immunotherapy-targeted-therapy-whats-the-difference/ [Accessed 29 May 2019]. 

[2] National Cancer Institute. (n.d.). NCI Dictionary of Cancer Terms. [online] Available at: https://www.cancer.gov/publications/dictionaries/cancer-terms/def/immunotherapy [Accessed 29 May 2019].

Imatinib

It «is a tyrosine-kinase inhibitor used in the treatment of multiple cancers. By preventing a tyrosine-kinase enzyme from phosphorylating subsequent proteins and initiating the signaling cascade necessary for cancer development, imatinib prevents the growth of, and leads to apoptosis in, cancer cells.»

Bibliographic reference: RadOncQuestions. Radoncquestions.com. https://www.radoncquestions.com. Published 2018. Accessed December 28, 2018.

ITV (internal target volume)

It consists of an internal margin added to the CTV to compensate for internal physiologic movement and variations in size, shape, and position of the CTV [1]. It's an expansion of CTV for internal (e.g. breathing) movement [2].

Bibliographic references:

[1] Reiff J. E. (2013). C. In: L. Brady and T. Yaeger, ed., Encyclopedia of Radiation Oncology, 1st ed. Springer-Verlag Berlin Heidelberg, pp.343-399.

[2] Balter J. Target definition (margin selection) for radiotherapy (IMRT). aapmorg. 2017. Available at: https://www.aapm.org/meetings/03SS/Presentations/Balter.pdf. Accessed September 11, 2017.

ICRU

International Commission on Radiation Units & Measurements, Inc.

Bibliographic reference: Icru.org. (2016). Home - International Commission on Radiation Units and Measurements (ICRU). [online] Available at: http://www.icru.org/ [Accessed 4 May 2016].