21 (Adele album) and vocal problems led to numerous alterations to the tour itinerary. The cancellation of the North American leg of the tour was due to a vocal haemorrhage on her vocal cords. The singer underwent corrective vocal surgery in November 2011 and cancelled all public appearances until February 2012. Adele performed "Rolling in the Deep" at the 2011 ECHO Awards, 2012 Grammy Awards and 2012 BRIT Awards ceremonies. "21" yielded five singles in total, including four worldwide releases. The lead single "Rolling in the Deep" was released in November 2010, and peaked the charts in the Netherlands, Germany, Belgium, Italy, and
Hitomi (singer) which was released as a digital single in September. On November 30, 2011, Hitomi released a new mini album entitled "Special", in which her songs featured in the NHK educational program "Hana Kappa" were included. This became her last release published by Avex. Hitomi also collaborated with Sfpr, fellow label mates from Maximum 10, in the song "Feeder", which was included in their debut album released on January 1, 2012. On October 10, 2012, she released her eleventh album "Möbius" (stylized as ∞). The album had no commercial singles like her previous work, although the Brian Lee-produced song "Up Down"