Sunday, 17 June 2018

PSAV (prostate specific antigen velocity)

Total PSA (prostate specific antigen) velocity, in ng/mL/year, is the change in total PSA values over time and it is «calculated as the running average of the rate of change during 3 consecutive visits by the equation 0.5{[(PSA2-PSA1)/(elapsed time in years)]+[(PSA3-PSA2)/(elapsed time in years)]}, where PSA1 is the first of the 3 measurements, PSA2 the second and PSA3 the third. Elapsed time refers to time between the 2 measurements [1]».
The rate of change in serum total PSA over time provides useful information and increases the specificity of PSA for cancer detection. Current recommendations for the use of PSAV include a collection of PSA levels over a period of no less than 18 months and the use of multiple values (minimum of 3) to perform the calculation. PSAV «has been best used in younger men who have elected to begin early detection programs before age 50». It «was designed to help avoid unnecessary, costly, and potentially morbid repeat biopsies in these men» [2]. «A rise in PSA of as little as 0.1 ng/ml per year is worrisome as to the long-term chance of being diagnosed with prostate cancer» [2,3]:

PSA VelocityProstate Cancer Risk by 10 Years
≤0.1 ng/ml/year3%
>0.1 ng/ml/year65%
Source: [2,3].

«Any rapid rise in PSA is worrisome both for the likelihood of developing cancer but of having more serious (high-grade prostate cancer.) A recent study [4] found that men whose PSA jumped more than 2 points in the year prior to being diagnosed had much higher death rate when treated with surgery (radical prostatectomy). Also, patients treated with radiation for prostate cancer whose PSA starts to rise do worse if the PSA doubles in less than 12 months» [2].
In patients with prostate cancer without metastases, those with a rapid PSAV and an otherwise long life expectancy should be encouraged to consider androgen deprivation therapy earlier [5].
A free online calculation can be found here: USRF - PSA Velocity [6].

Bibliographic references:
[1] Khan MA, Carter HB, Epstein JI, et al. Can prostate specific antigen derivatives and pathological parameters predict significant change in expectant management criteria for prostate cancer? J Urol. 2003 Dec;170(6 Pt 1):2274-8. Available at: https://doi.org/10.1097/01.ju.0000097124.21878.6b.
[2] PSA Velocity. Aboutcancercom. Available at: http://www.aboutcancer.com/psa_velocity.htm. Accessed June 17, 2018.
[3] Fang J, Metter EJ, Landis P, Carter HB. PSA velocity for assessing prostate cancer risk in men with PSA levels between 2.0 and 4.0 ng/ml. Urology. 2002 Jun;59(6):889-93; discussion 893-4. Available at: https://doi.org/10.1016/S0090-4295(02)01646-1.
[4] D'Amico AV, Chen MH, Roehl KA, Catalona WJ. Preoperative PSA velocity and the risk of death from prostate cancer after radical prostatectomy. N Engl J Med. 2004 Jul 8;351(2):125-35. Available at: https://doi.org/10.1056/NEJMoa032975.
[5] Mohler J, Lee R, Antonarakis E, et al. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) – Prostate Cancer – Version 2.2018 - March 8, 2018. Nccnorg. 2018. Available at: https://www.nccn.org/professionals/physician_gls/pdf/prostate.pdf. Accessed June 17, 2018.
[6] USRF - PSA Velocity. Usrforg. Available at: https://www.usrf.org/questionnaires/PSA_Velocity.html. Accessed June 17, 2018.

Tuesday, 5 June 2018

The scarcity of funding for radiotherapy trials

Characteristics of radiotherapy trials compared With other oncological clinical trials in the past 10 years.

The limited number of and the scarcity of funding for radiotherapy trials is concerning given the integral role of radiotherapy in the clinical management of patients with cancer worldwide. A multidisciplinary collaboration to promote and fund more radiotherapy research is warranted.

Liu X, Zhang Y, Tang LL, et al. JAMA Oncol. 2018 May 17. Available at: https://doi.org/10.1001/jamaoncol.2018.0887.

Sunday, 3 June 2018

Pancoast syndrome or Pancoast's syndrome

«Tumor involving the upper part of the lung, with invasion of the surrounding structures as the plexus brachialis, ribs, and extending in the nodes, possibly causing a Claude-Bernard Horner syndrome. Now currently named superior pulmonary sulcus tumor [1].»
«This is accompanied by the following: severe pain in the shoulder region radiating toward the axilla and scapula, with later extension along the ulnar aspect of the arm to the hand, atrophy of hand and arm muscles, Horner syndrome (...), and compression of the blood vessels with edema [2].»
Bibliographic references:
[1] Debois JM. The Eponyms Of Oncology. Pharmacia & Upjohn; 1996.
[2] D'Silva KJ, May SK. Pancoast Syndrome: Practice Essentials, Pathophysiology, Etiology. Medscape Drugs & Diseases. 2017. Available at: https://emedicine.medscape.com/article/284011-overview. Accessed June 3, 2018.

Saturday, 2 June 2018

Horner syndrome, Horner’s syndrome, Claude-Bernard Horner syndrome, or oculosympathetic paresis

Horner syndrome «is a combination of symptoms that arises when a group of nerves known as the sympathetic trunk is damaged [1]». It «results from an interruption of the sympathetic nerve supply to the eye and is characterized by the classic triad of miosis (ie, constricted pupil [2]», by inactivation of the dilator muscle [1]), partial ptosis [2] (a weak, droopy eyelid, by inactivation of the superior tarsal muscle) [1], «loss of hemifacial sweating (ie, anhidrosis) [2]», «with apparent enophthalmos (inset eyeball) [1]». «The term Horner syndrome is commonly used in English-speaking countries, whereas the term Bernard-Horner syndrome is common in France [2]».
«The nerves of the sympathetic trunk arise from the spinal cord in the chest, and from there ascend to the neck and face. The nerves are part of the sympathetic nervous system, a division of the autonomic (or involuntary) nervous system [1].»
Bibliographic references:
[1] Horner's syndrome. Enwikipediaorg. 2018. Available at: https://en.wikipedia.org/wiki/Horner%27s_syndrome. Accessed June 2, 2018.
[2] Bardorf CM, Stavern GV, Garcia-Valenzuela E. Horner Syndrome: Overview, Anatomy, Pathophysiology. Medscape Drugs & Diseases. 2017. Available at: https://emedicine.medscape.com/article/1220091-overview. Accessed June 2, 2018.

Saturday, 28 April 2018

SABR (stereotactic ablative radiotherapy)

It is a stereotactic radiotherapy with dose by a fraction greater than 8 Gy, that allows stopping both cellular division and cellular function, overwhelms tumor repair, and is more likely to cause «late» effects.
Bibliographic reference: Timmerman RD. An overview of hypofractionation and introduction to this issue of seminars in radiation oncology. Semin Radiat Oncol. 2008 Oct;18(4):215-22. Available at: https://doi.org/10.1016/j.semradonc.2008.04.001.

Wednesday, 21 February 2018

Gleason score

«The Gleason is a grade assigned to prostate cancer specimens that reflects the degree of aggressiveness based on the tumor's resemblance to normal glandular tissue. A primary (or predominant) pattern is recorded followed by a secondary or lesser pattern. The Gleason score is the sum of the primary and secondary pattern values and can be between 2 and 10» [1].

The original Gleason grading system diagram:

Source: Gordetsky J, Epstein J. Grading of prostatic adenocarcinoma: current state and prognostic implications. Diagn Pathol. 2016 Mar 9;11:25. Available at: https://doi.org/10.1186/s13000-016-0478-2. The link to the Creative Commons Attribution 4.0 International License is http://creativecommons.org/licenses/by/4.0/.

«Grade 1: small, well-formed glands, closely packed;
Grade 2: well-formed glands, but more tissue between them;
Grade 3: darker cells, some of which have left the gland and are invading the surrounding tissue;
Grade 4: few recognizable glands with many cells invading the surrounding tissue;
Grade 5: no recognizable glands; sheets of cells throughout the surrounding tissue» [1].
The current guidelines for the Gleason grading system and recent changes from the 2014 International Society of Urological Pathology (ISUP) consensus conference on Gleason grading of prostatic carcinoma include five distinct grade groups based on the modified Gleason score groups. Grade Group 1 = Gleason score ≤6, Grade Group 2 = Gleason score 3 + 4 = 7, Grade Group 3 = Gleason score 4 + 3 = 7, Grade Group 4 = Gleason score 8, Grade Group 5 = Gleason scores 9 and 10. This new ISUP grading system is simpler and more accurately reflects prostate cancer biology, and it is recommended by the World Health Organization (WHO) to be used in conjunction with Gleason grading [10].
Bibliographic references:
[1] Shah A. 53 - Low-Risk Prostate Cancer. In: Hristov B, Lin S, Christodouleas J. Radiation Oncology. 2nd ed. Philadelphia, USA: Wolters Klumer Health; 2015:364.
[2] Gordetsky J, Epstein J. Grading of prostatic adenocarcinoma: current state and prognostic implications. Diagn Pathol. 2016 Mar 9;11:25. Available at: https://doi.org/10.1186/s13000-016-0478-2The link to the Creative Commons Attribution 4.0 International License is http://creativecommons.org/licenses/by/4.0/.

Ratio of free to total PSA (prostate-specific antigen)

«The end product of normal PSA (prostate-specific antigen) biosynthesis within the prostate epithelium and ducts is inactive "free PSA", a fraction of which diffuses into circulation. In prostate cancer, tumors disrupt the prostate basement membrane and allow precursor forms of PSA to leak into the circulation, which decreases the relative proportion of free PSA. Hence, the ratio of free-to-total PSA will be lower in men with prostate cancer. A ratio of <7% is highly suspicious for prostate cancer, whereas a ratio of >25% is rarely associated with malignancy.»
Bibliographic reference: Shah A. 53 - Low-Risk Prostate Cancer. In: Hristov B, Lin S, Christodouleas J. Radiation Oncology. 2nd ed. Philadelphia, USA: Wolters Klumer Health; 2015:366.

Sunday, 4 February 2018

Abscopal effect


Reirradiation in breast cancer

Photo by Dr. Francisco Branco, slide by Dr. Pedro Fernandes, in Breast Cancer Weekend, on January 26, 2018, Instituto Português de Oncologia - Porto - Francisco Gentil, Porto, Portugal.