agxАндрология и генитальная хирургияAndrology and Genital Surgery2070-97812412-890210.17650/2070-9781-2022-23-2-34-46agx-563Research ArticleОРИГИНАЛЬНАЯ СТАТЬЯORIGINAL REPORTСравнительный анализ малоинвазивных методов лечения локализованного рака предстательной железыComparative analysis of minimally invasive methods of treatment of localized prostate cancerhttps://orcid.org/0000-0001-9056-9791ЧиненовД. В.ChinenovD. V.

Денис Владимирович Чиненов

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Denis Vladimirovich Chinenov

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

chinenov_dv@mail.ruhttps://orcid.org/0000-0003-1121-9430ШпотьЕ. В.ShpotE. V.

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

https://orcid.org/0000-0001-8425-9017ЧерновЯ. Н.ChernovYa. N.

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

https://orcid.org/0000-0002-1846-0270ЦуккиевЗ. К.TsukkievZ. K.

119991 Москва, ул. Трубецкая, 8, стр. 2

Bld. 2, 8 Trubetskaya St., Moscow 119991

https://orcid.org/0000-0001-6767-3224ВотяковА. Ю.VotyakovA. Yu.

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

https://orcid.org/0000-0003-2489-606XКурбановА. А.KurbanovA. A.

119991 Москва, ул. Трубецкая, 8, стр. 2

Bld. 2, 8 Trubetskaya St., Moscow 119991

https://orcid.org/0000-0003-0548-190XИсмаиловХ. М.IsmailovH. M.

119991 Москва, ул. Трубецкая, 8, стр. 2

Bld. 2, 8 Trubetskaya St., Moscow 119991

https://orcid.org/0000-0001-8099-3599ЛернерЮ. В.LernerYu. V.

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

https://orcid.org/0000-0001-7787-1240РапопортЛ. М.RapoportL. M.

119435 Москва, ул. Большая Пироговская, 2, стр. 1

Bld. 1, 2 Bolshaya Pirogovskaya St., Moscow 119992

Клиника урологии им. Р.М. Фронштейна ФГАОУ ВО Первый Московский государственный медицинский университет им. И.М. Сеченова Минздрава России (Сеченовский Университет)РоссияR.M. Fronstein Urology Clinic, I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University)Russian FederationФГАОУ ВО Первый Московский государственный медицинский университет им. И.М. Сеченова Минздрава России (Сеченовский Университет)РоссияI.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenov University)Russian Federation2022230620222323446Copyright © Чиненов Д.В., Шпоть Е.В., Чернов Я.Н., Цуккиев З.К., Вотяков А.Ю., Курбанов А.А., Исмаилов Х.М., Лернер Ю.В., Рапопорт Л.М., 20222022Чиненов Д.В., Шпоть Е.В., Чернов Я.Н., Цуккиев З.К., Вотяков А.Ю., Курбанов А.А., Исмаилов Х.М., Лернер Ю.В., Рапопорт Л.М.Chinenov D.V., Shpot E.V., Chernov Y.N., Tsukkiev Z.K., Votyakov A.Y., Kurbanov A.A., Ismailov H.M., Lerner Y.V., Rapoport L.M.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://agx.elpub.ru/jour/article/view/563

Цель исследования – изучение функциональных и онкологических результатов лечения локализованного рака предстательной железы (РПЖ) с помощью малоинвазивных методов.

Материалы и методы

Материалы и методы. В нашем исследовании представлены 160 пациентов с локализованным РПЖ, которым было проведено лечение малоинвазивными методами: криобляция (n = 53), брахитерапия (n = 52), высокоинтенсивная фокусированная ультразвуковая (ВИФУ) терапия (n = 55). В качестве оценки онкологического результата использовали показатели общего простатического специфического антигена и результаты повторных трансректальных биопсий предстательной железы. Оценка функциональных показателей и качества жизни проводилась по результатам анкетирования c использованием опросников МИЭФ-5 (международный индекс эректильной функции), IPSS (International Prostate Symptom Score, международная шкала оценки симптомов при заболеваниях пред стательной железы), QoL (Quality of Life, опросник по качеству жизни), а также анализа показателя Qmax (максимальная скорость мочеиспускания).

Результаты

Результаты. Результаты онкологического контроля по данным положительных повторных биопсий были хуже у пациентов после криоабляции (7,54 %), лучшие онкологические результаты наблюдались у пациентов после брахитерапии. Показатель по шкале IPSS был статистически значимо хуже в группе брахитерапии по сравнению с другими группами в раннем послеоперационном периоде, однако данные различия не достигают уровня статистической значимости в позднем периоде у пациентов групп брахитерапии и криоабляции. Пациенты группы криоабляции продемонстрировали худшие показатели МИЭФ-5 в раннем послеоперационном периоде, в позднем периоде наблюдения показатели эректильной функции у пациентов группы криоабляции статистически значимо не отличались от таковых у пациентов после брахитерапии. Пациенты после ВИФУ-терапии показали меньше случаев эректильной дисфункции de novo за период наблюдения в 3 года, более высокие средние показатели МИЭФ-5, более низкие показатели баллов IPSS и лучшие результаты по опроснику QoL.

Выводы

Выводы. Отдаленные онкологические результаты в целом сопоставимы, однако частота рецидивов несколько выше у пациентов после криоабляции. Частота рецидивов РПЖ была статистически значимо выше у пациентов группы ISUP 3. У пациентов группы ВИФУ-терапии показатели качества мочеиспускания были лучше, чем у пациентов других групп, что можно связать с предварительно выполненной им лазерной энуклеацией гиперплазии предстательной железы. Преимущество у пациентов после ВИФУ-терапии наблюдалось при сравнении по показателям МИЭФ-5, таким образом, ВИФУ-терапия оказала лучшее влияние на качество жизни пациентов с локализованным РПЖ. 

The purpose of this work is to study the functional and oncological results of minimally invasive methods in patients with verified prostate cancer.

Materials and methods

Materials and methods. In our study, 160 patients with identified prostate cancer were presented, treatment was carried out with minimally invasive methods (methods of cryoablation (n = 53), brachytherapy (n = 52) and HIFU therapy (n = 55)). A qualitative assessment of the oncological outcome revealed high levels of prostate-specific antigen (PSA) and the results of repeated transrectal prostate biopsies. The evaluation of functional indicators and quality of life was carried out according to the results of the IIEF-5 (International Index of Erectile Function), IPSS (International Prostate Symptom Score), QoL (Quality of Life), Qmax (maximum urination rate of function).

Results

Results. The results of oncological control according to the data of positive repeated biopsies were worse in patients after cryoablation (7.54 %), the best indicators of oncological results were observed in patients after brachytherapy. Looking at the IPSS results, it is possible to detect statistical signs of higher scores in the brachytherapy group when various signs are found in the postoperative period, however, these differences do not reach statistical signs in the late period in patients of group brachytherapy and cryoablation. Patients of the cryoablation group showed higher levels of the IIEF-5 in the postoperative period, in the late period of observation of erectile function in patients  of the cryoablation group, the statistical data did not differ from those in patients after brachytherapy. Patients after HIFU therapy showed a decrease in de novo erectile dysfunction over a 3-year follow-up period, above average IIEF5 scores, below IPSS scores, and better QoL results.

Conclusion

Conclusion. Long-term oncological results are, in general, revisions, however, the recurrence rate is slightly higher in patients after cryoablation. Prostate cancer recurrence was detected in patients of the ISUP 3 group. In patients after HIFU therapy, the quality of urination is higher than in patients of other groups, which can be associated with the laser enucleation of prostate hyperplasia performed by him. The advantage in patients after HIFU therapy was observed in the detection of IIEF-5, thus HIFU therapy had a better effect on the quality of life of patients with pathological prostate cancer.

брахитерапиякриоабляциявысокоинтенсивная фокусированная ультразвуковая терапиялокализованный рак предстательной железыbrachytherapycryoablationhigh-intensity focused ultrasound therapyprostate cancer detectionReferencesPettersson A., Robinson D., Garmo H. et al. Age at diagnosis and prostate cancer treatment and prognosis: a population-based cohort study. Ann Oncol 2018;29(2):377–85. DOI: 10.1093/annonc/mdx742.Pettersson A., Robinson D., Garmo H. et al. Age at diagnosis and prostate cancer treatment and prognosis: a population-based cohort study. Ann Oncol 2018;29(2):377–85. DOI: 10.1093/annonc/mdx742.Wilt T.J., MacDonald R., Rutks I. et al. Systematic review: comparative effectiveness and harms of treatments for clinically localized prostate cancer. Ann Intern Med 2008;148(6):435–48. DOI: 10.7326/0003-4819-148-6200803180-00209.Wilt T.J., MacDonald R., Rutks I. et al. Systematic review: comparative effectiveness and harms of treatments for clinically localized prostate cancer. Ann Intern Med 2008;148(6):435–48. DOI: 10.7326/0003-4819-148-6200803180-00209.Ficarra V., Novara G., Rosen R.C. et al. Systematic review and metaanalysis of studies reporting urinary continence recovery after robotassisted radical prostatectomy. Eur Urol 2012;62(3):405–17. DOI: 10.1016/j.eururo.2012.05.045.Ficarra V., Novara G., Rosen R.C. et al. Systematic review and metaanalysis of studies reporting urinary continence recovery after robotassisted radical prostatectomy. Eur Urol 2012;62(3):405–17. DOI: 10.1016/j.eururo.2012.05.045.Morash C., Tey R., Agbassi C. et al. Active surveillance for the management of localized prostate cancer: guideline recommendations. Can Urol Assoc J 2015;9(5–6):171–78. DOI: 10.5489/cuaj.2806.Morash C., Tey R., Agbassi C. et al. Active surveillance for the management of localized prostate cancer: guideline recommendations. Can Urol Assoc J 2015;9(5–6):171–78. DOI: 10.5489/cuaj.2806.Richard P.O., Alibhai S.M., Panzarella T. et al. The uptake of active surveillance for the management of prostate cancer: a population-based analysis. Can Urol Assoc J 2016;10(9–10):333–8. DOI: 10.5489/cuaj.3684.Richard P.O., Alibhai S.M., Panzarella T. et al. The uptake of active surveillance for the management of prostate cancer: a population-based analysis. Can Urol Assoc J 2016;10(9–10):333–8. DOI: 10.5489/cuaj.3684.Sankar A., Johnson S.R., Beattie W.S. et al. Reliability of the American Society of Anesthesiologists physical status scale in clinical practice. Br J Anaesth 2014;113(3):424–32. DOI: 10.1093/bja/aeu100.Sankar A., Johnson S.R., Beattie W.S. et al. Reliability of the American Society of Anesthesiologists physical status scale in clinical practice. Br J Anaesth 2014;113(3):424–32. DOI: 10.1093/bja/aeu100.Cordeiro E.R., Cathelineau X., Thüroff S. et al. High-intensity focused ultra-sound (HIFU) for definitive treatment of prostate cancer. BJU Int 2012;110(9):1228–42. DOI: 10.1111/j.1464-410X.2012.11262.x.Cordeiro E.R., Cathelineau X., Thüroff S. et al. High-intensity focused ultra-sound (HIFU) for definitive treatment of prostate cancer. BJU Int 2012;110(9):1228–42. DOI: 10.1111/j.1464-410X.2012.11262.x.Wilt T.J., Brawer M.K., Jones K.M. et al. Radical prostatectomy versus observation for localized prostate cancer. N Engl J Med 2012;367(3):203–3. DOI: 10.1056/NEJMoa1113162.Wilt T.J., Brawer M.K., Jones K.M. et al. Radical prostatectomy versus observation for localized prostate cancer. N Engl J Med 2012;367(3):203–3. DOI: 10.1056/NEJMoa1113162.Bill-Axelson A., Holmberg L., Garmo H. et. al. Radical prostatectomy or watchful waiting in early prostate cancer. N Engl J Med 2014:370(10):932–42. DOI: 10.1056/NEJMoa1311593.Bill-Axelson A., Holmberg L., Garmo H. et. al. Radical prostatectomy or watchful waiting in early prostate cancer. N Engl J Med 2014:370(10):932–42. DOI: 10.1056/NEJMoa1311593.Chiang P.H., Liu Y.Y. Comparisons of oncological and functional outcomes among radical retropubic prostatectomy, high dose rate brachytherapy, cryoablation and high-intensity focused ultrasound for localized prostate cancer. Springerplus 2016;5(1):1905. DOI: 10.1186/s40064-016-3584-4.Chiang P.H., Liu Y.Y. Comparisons of oncological and functional outcomes among radical retropubic prostatectomy, high dose rate brachytherapy, cryoablation and high-intensity focused ultrasound for localized prostate cancer. Springerplus 2016;5(1):1905. DOI: 10.1186/s40064-016-3584-4.Tay K.J., Amin M.B., Ghai S. et al. Surveillance after prostate focal therapy. World J Urol 2019;37(3):397–407. DOI: 10.1007/s00345-018-2363-y.Tay K.J., Amin M.B., Ghai S. et al. Surveillance after prostate focal therapy. World J Urol 2019;37(3):397–407. DOI: 10.1007/s00345-018-2363-y.Muller B.G., van den Bos W., Brausi M. et al. Role of multiparametric magnetic resonance imaging (MRI) in focal therapy for prostate cancer: a Delphi consensus project. BJU Int 2014;114(5):698–707. DOI: 10.1111/bju.12548.Muller B.G., van den Bos W., Brausi M. et al. Role of multiparametric magnetic resonance imaging (MRI) in focal therapy for prostate cancer: a Delphi consensus project. BJU Int 2014;114(5):698–707. DOI: 10.1111/bju.12548.Zimmermann J.S., MD, Osieka R., Bruns T. et al. Five-year effectiveness of low-dose-rate brachytherapy: comparisons with nomogram predictions in patients with non-metastatic prostate cancer presenting significant control of intra- and periprostatic disease. J Contemp Brachytherapy 2018;10(4):297–305. DOI: 10.5114/jcb.2018.77949.Zimmermann J.S., MD, Osieka R., Bruns T. et al. Five-year effectiveness of low-dose-rate brachytherapy: comparisons with nomogram predictions in patients with non-metastatic prostate cancer presenting significant control of intra- and periprostatic disease. J Contemp Brachytherapy 2018;10(4):297–305. DOI: 10.5114/jcb.2018.77949.Fellin G., Mirri M.A., Santoro L. et al. Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions. Br J Radiol 2016;89(1065):20150981. DOI: 10.1259/bjr.20150981.Fellin G., Mirri M.A., Santoro L. et al. Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions. Br J Radiol 2016;89(1065):20150981. DOI: 10.1259/bjr.20150981.Rodríguez S.A., Arias Fúnez F., Bueno Bravo C. et al. Cryotherapy for primary treatment of prostate cancer: intermediate term results of a prospective study from a single institution. Prostate Cancer 2014;2014:571576. DOI: 10.1155/2014/571576.Rodríguez S.A., Arias Fúnez F., Bueno Bravo C. et al. Cryotherapy for primary treatment of prostate cancer: intermediate term results of a prospective study from a single institution. Prostate Cancer 2014;2014:571576. DOI: 10.1155/2014/571576.Limani K., Aoun F., Holz S. et al. Single high intensity focused ultrasound session as a whole gland primary treatment for clinically localized prostate cancer: 10-year outcomes. Prostate Cancer 2014;2014:186782. DOI: 10.1155/2014/186782.Limani K., Aoun F., Holz S. et al. Single high intensity focused ultrasound session as a whole gland primary treatment for clinically localized prostate cancer: 10-year outcomes. Prostate Cancer 2014;2014:186782. DOI: 10.1155/2014/186782.El Fegoun A.B., Barret E., Prapotnich D. et al. Focal therapy with high-intensity focused ultrasound for prostate cancer in the elderly. A feasibility study with 10 years follow-up. Int Braz J Urol 2011;37(2):213–9; discussion 220–2. DOI: 10.1590/s1677-55382011000200008.El Fegoun A.B., Barret E., Prapotnich D. et al. Focal therapy with high-intensity focused ultrasound for prostate cancer in the elderly. A feasibility study with 10 years follow-up. Int Braz J Urol 2011;37(2):213–9; discussion 220–2. DOI: 10.1590/s1677-55382011000200008.Ahmed H.U., Dickinson L., Charman S. et al. Focal ablation targeted to the index lesion in multifocal localised prostate cancer: a prospective development study. Eur Urol 2015;68(6):927–36. DOI: 10.1016/j.eururo.2015.01.030.Ahmed H.U., Dickinson L., Charman S. et al. Focal ablation targeted to the index lesion in multifocal localised prostate cancer: a prospective development study. Eur Urol 2015;68(6):927–36. DOI: 10.1016/j.eururo.2015.01.030.Feijoo E.R.C., Sivaraman A., Barret E. et al. Focal high intensity focused ultrasound targeted hemiablation for unilateral prostate cancer: a prospective evaluation of oncologic and functional outcomes. Eur Urol 2016;69(2):214–20. DOI: 10.1016/j.eururo.2015.06.018.Feijoo E.R.C., Sivaraman A., Barret E. et al. Focal high intensity focused ultrasound targeted hemiablation for unilateral prostate cancer: a prospective evaluation of oncologic and functional outcomes. Eur Urol 2016;69(2):214–20. DOI: 10.1016/j.eururo.2015.06.018.van der Poel H.G., van den Bergh R.C., Briers E. et al. Focal therapy in primary localised prostate cancer: The European Association of Urology position in 2018. Eur Urol 2018;74(1):84–91. DOI: 10.1016/j.eururo.2018.01.001.van der Poel H.G., van den Bergh R.C., Briers E. et al. Focal therapy in primary localised prostate cancer: The European Association of Urology position in 2018. Eur Urol 2018;74(1):84–91. DOI: 10.1016/j.eururo.2018.01.001.Mendez M.H., Passoni N.M., Pow-Sang J. et al. Comparison of outcomes between preoperatively potent men treated with focal versus whole gland cryotherapy in a matched population. J Endourol 2015;29(10):1193–8. DOI: 10.1089/end.2014.0881.Mendez M.H., Passoni N.M., Pow-Sang J. et al. Comparison of outcomes between preoperatively potent men treated with focal versus whole gland cryotherapy in a matched population. J Endourol 2015;29(10):1193–8. DOI: 10.1089/end.2014.0881.Valerio M., Shah T.T., Shah P. et al. Magnetic resonance imaging-transrectal ultrasound fusion focal cryotherapy of the prostate: a prospective development study. Urol Oncol 2017;35(4):150.e1–e7. DOI: 10.1016/j.urolonc.2016.11.008.Valerio M., Shah T.T., Shah P. et al. Magnetic resonance imaging-transrectal ultrasound fusion focal cryotherapy of the prostate: a prospective development study. Urol Oncol 2017;35(4):150.e1–e7. DOI: 10.1016/j.urolonc.2016.11.008.King M.T., Nguyen P.L., Boldbaatar N. et al. Long-term outcomes of partial prostate treatment with magnetic resonance imaging-guided brachytherapy for patients with favorable-risk prostate cancer. Cancer 2018;124(17):3528–35. DOI: 10.1002/cncr.31568.King M.T., Nguyen P.L., Boldbaatar N. et al. Long-term outcomes of partial prostate treatment with magnetic resonance imaging-guided brachytherapy for patients with favorable-risk prostate cancer. Cancer 2018;124(17):3528–35. DOI: 10.1002/cncr.31568.Merrick G.S., Butler W.M., Galbreath R.W. et al. Stratification of brachytherapytreated intermediate-risk prostate cancer patients into favorable and unfavorable cohorts. J Contemp Brachytherapy 2015;7(6):430–6. DOI: 10.5114/jcb.2015.56763.Merrick G.S., Butler W.M., Galbreath R.W. et al. Stratification of brachytherapytreated intermediate-risk prostate cancer patients into favorable and unfavorable cohorts. J Contemp Brachytherapy 2015;7(6):430–6. DOI: 10.5114/jcb.2015.56763.Lucan V.C., Lugnani F., Butticè S. et al. Cryotherapy for low risk prostate cancer, oncological and functional medium term outcomes: a three center prospective study. Arch Ital Urol Androl 2017;89(2):97–101. DOI: 10.4081/aiua.2017.2.97.Lucan V.C., Lugnani F., Butticè S. et al. Cryotherapy for low risk prostate cancer, oncological and functional medium term outcomes: a three center prospective study. Arch Ital Urol Androl 2017;89(2):97–101. DOI: 10.4081/aiua.2017.2.97.Schoentgen N., Marolleau J., Delage F. et al. Prospective four years of evaluation of erectile function after low-dose-rate prostate brachytherapy using baseline IIEF-5 >16. J Contemp Brachytherapy 2019;11(3):195–200. DOI: 10.5114/jcb.2019.85793.Schoentgen N., Marolleau J., Delage F. et al. Prospective four years of evaluation of erectile function after low-dose-rate prostate brachytherapy using baseline IIEF-5 >16. J Contemp Brachytherapy 2019;11(3):195–200. DOI: 10.5114/jcb.2019.85793.Liu Y.Y., Chiang P.H. Comparisons of oncological and functional outcomes between primary whole-gland cryoablation and high-intensity focused ultrasound for localized prostate cancer. Ann Surg Oncol 2016;23(1):328–34. DOI: 10.1245/s10434-015-4686-x.Liu Y.Y., Chiang P.H. Comparisons of oncological and functional outcomes between primary whole-gland cryoablation and high-intensity focused ultrasound for localized prostate cancer. Ann Surg Oncol 2016;23(1):328–34. DOI: 10.1245/s10434-015-4686-x.Wolff R.F., Ryder S., Bossi A. et al. A systematic review of randomised controlled trials of radiotherapy for localised prostate cancer. Eur J Cancer 2015;51(16):2345–67. DOI: 10.1016/j.ejca.2015.07.019.Wolff R.F., Ryder S., Bossi A. et al. A systematic review of randomised controlled trials of radiotherapy for localised prostate cancer. Eur J Cancer 2015;51(16):2345–67. DOI: 10.1016/j.ejca.2015.07.019.Hatiboglu G., Popeneciu I.V., Deppert M. et al. Quality of life and functional outcome after infravesical desobstruction and HIFU treatment for localized prostate cancer. BMC Urol 2017;17(1):5. DOI: 10.1186/s12894-017-0198-2.Hatiboglu G., Popeneciu I.V., Deppert M. et al. Quality of life and functional outcome after infravesical desobstruction and HIFU treatment for localized prostate cancer. BMC Urol 2017;17(1):5. DOI: 10.1186/s12894-017-0198-2.Onishi K., Tanaka N., Miyake M. et al. Changes in lower urinary tract symptoms after iodine-125 brachytherapy for prostate cancer. Clin Transl Radiat Oncol 2018;14:51–8. DOI: 10.1016/j.ctro.2018.11.001.Onishi K., Tanaka N., Miyake M. et al. Changes in lower urinary tract symptoms after iodine-125 brachytherapy for prostate cancer. Clin Transl Radiat Oncol 2018;14:51–8. DOI: 10.1016/j.ctro.2018.11.001.Yu Y.D., Kang M.H., Choi C.I. et al. Clinical efficacy of combination therapy with an alpha blocker and low-dose sildenafil on post-therapy lower urinary tract symptoms after low-dose-rate brachytherapy for prostate cancer. World J Urol 2016;34(9):1269–74. DOI: 10.1007/s00345-016-1777-7.Yu Y.D., Kang M.H., Choi C.I. et al. Clinical efficacy of combination therapy with an alpha blocker and low-dose sildenafil on post-therapy lower urinary tract symptoms after low-dose-rate brachytherapy for prostate cancer. World J Urol 2016;34(9):1269–74. DOI: 10.1007/s00345-016-1777-7.

The authors declare that there are no conflicts of interest present.