Dosimetric Predictors of Acute and Chronic Alopecia in Primary Brain Cancer Patients Treated With Volumetric Modulated Arc Therapy

Abstract

Purpose: To determine dose constraints that correlate with alopecia in patients treated with photon-based Volumetric Modulated Arc Therapy (VMAT) for primary brain tumors.Methods: During the treatment planning process, the scalp was drawn as a region of interest. Dose received by 0.1 cc (D 0.1cc ), mean dose (D mean ), absolute volumes receiving different doses (V 16Gy , V 20Gy , V 25Gy , V 30Gy , V 35Gy , V 40Gy , and V 43Gy ) were registered for the scalp. Alopecia was assessed according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Receiver operating characteristics (ROC) curve analysis was used to identify parameters associated with hair-loss.Results: One-hundred and one patients were included in this observational study. At the end of radiotherapy (RT), 5 patients did not develop alopecia (D mean scalp 3.1 Gy). The scalp of the patients with G1 (n = 11) and G2 (n = 85) alopecia received D mean of 10.6 Gy and 11.8 Gy, respectively. At ROC analysis, V 16Gy20Gy ≥ 5.2 cc were the strongest predictors of acute alopecia risk. Chronic hair-loss assessment was available for 74 patients: median time to recovery from G2 alopecia was 5, 9 months. The actuarial rate of hair regrowth was 98.1% at 18 months after the end of RT. At ROC analysis, V 40Gy43Gy ≥2.2 cc were the strongest predictors of chronic G2-alopecia risk. V 20Gy, V 40Gy , and D 0,1cc were shown to be independent variables according to correlation coefficient r.Conclusions: V 20Gy and V 40Gy were the strongest predictors for acute and chronic G2 hair-loss, respectively. The low-dose bath typical of VMAT corresponds to large areas of acute but transient alopecia. However, the steep dose gradient of VMAT allows to reduce the areas of the scalp that receive higher doses, minimizing the risk of permanent alopecia. Scoccianti et al. Predictors of Radiotherapy-Induced AlopeciaThe application of our dosimetric findings for the scalp may help in reducing the alopecia risk and also in estimating the probability of hair-loss during patient counseling before starting radiotherapy.

Alopecia and neurocognitive dysfunction in Glioblastoma multiforme patients- Prevention feasibillity by dosimetric analysis in conformal radiotherapy techniques

“…The V20 and V40 have been proved to be strong predictors of acute and chronic radiation induced alopecia respectively. 7 Both the parameters were significantly lesser in IMRT technique. Persistent alopecia after six months of radiation affects approximately 60% of patients.…”

“…The dose constraints for OAR's were prescribed as per EORTC recommendations. 7 PRV Optic Chiasma Dmax < 55 Gy; PRV Brainstem Dmax < 54 Gy, V59 Gy < 10 cc ; PRV Cochlea Dmean < 45Gy; Lens < 6 -10 Gy; Eyes Dmax < 50 Gy, PRV Optic Nerves Dmax < 54 Gy.…”

The global regulatory logic of organ regeneration: circuitry lessons from skin and its appendages

“…In addition to loss of stem cells, the stroma cells that form the stem cell niche may also be damaged and fail to support tissue regeneration. IR may induce permanent hair loss, which is related to stem cell damage and/or collapse of the immune privilege of the HFs (Bertolini et al, 2020;Scoccianti et al, 2020). In IRinduced damage to the oral mucosa and salivary glands, the regeneration process often fails, leading to permanent xerostemia and other related symptoms (Acauan et al, 2015;Marmary et al, 2016;Rocchi & Emmerson, 2020).…”

Management of complications from brain metastasis treatment: a narrative review

“…However, in others, chronic alopecia (incomplete hair regrowth >6 months after treatment) may occur. Only patients who experience acute alopecia can develop chronic radiation-induced alopecia (33).…”

“…Patients with significant chronic alopecia can also be referred for hair prosthesis. Scalp-sparing radiation delivery techniques utilizing intensity-modulated radiation therapy (IMRT) have been developed which appear to both reduce the severity of acute alopecia and significantly reduce the likelihood of chronic alopecia (33,36,37). It should be noted that despite a reduction in scalp radiation dose with IMRT, most patients will still experience acute alopecia with >50% hair loss and this technique should therefore be reserved for patients with an expected survival of >4-6 months or for those receiving IMRT for other indications (i.e., hippocampal avoidance).…”