In more sad news to report from the music world, influential rapper Guru (nĂ© Keith Elam) from the legendary hip-hop duo GangStarr, has passed away after succumbing to cancer. This update is the latest in a string of reports about the rapper’s health, including one from Feb. 28, when he was reported to have suffered from cardiac arrest, March 2, when he had undergone surgery and March 3, when he awoke from a subsequent coma. He was 43.

According to close friend and recent collaborator/producer Superproducer Solar, of 7Grand Records, Guru had been battling the unspecified cancer for over a year, and had finally lost his battle with the disease after trying numerous treatments and consulting numerous physicians. Solar also released a letter that had allegedly been written by Guru while on his deathbed, which gives Solar control of his name and likeness, but also gives him custody of Guru’s son.

“Solar and his family is my family and I love them dearly and I expect my family, friends, and fans to respect that, regardless to anybody’s feelings on the matter,” the letter reads. “It is my wish that counts. This being said I am survived by the love of my life, my sun [sic] KC, who I trust will be looked after by Solar and his family as their own. Any awards or tributes should be accepted, organised, approved by Solar on behalf of myself and my son until he is of age to accept on his own.

“I do not wish my ex-DJ [Premier] to have anything to do with my name likeness, events tributes etc. I had nothing to do with him in life for over seven years and want nothing to do with him in death. Solar has my life story and is well informed on my family situation, as well as the real reason for separating from my ex-DJ. As the sole founder of GangStarr, I am very proud of what GangStarr has meant to the music world and fans. I equally am proud of my Jazzmatazz series and as the father of Hip-Hop/Jazz.”

The entire letter can be found here.

Guru, while born and raised in Boston, moved to Brooklyn in the ’80s, where he collaborated with The 45 King to release a few singles, later pairing up with DJ Premier to release six studio albums over the course of fourteen years. The two had unofficially separated in 2004, due to what was cited as “creative and personal differences,” after Premier abruptly left the duo’s European tour to return to the U.S., and Guru finished the tour with a different DJ.

DJ Premier wrote on his blog site: “Guru has passed away yesterday morning [April 19] after a long battle with cancer. … According to Solar, Guru suffered from the malicious illness for over a year and after numerous special treatments under the supervision of medical specialists failed, the legendary MC succumbed to the disease. Guru always tried to keep this harrowing diagnosis in private but in early 2010 he had to admit himself to hospital due to serious effects caused by the disease.”

He later posted on Twitter, “I can’t believe it… RIP Guru.”

Yet to comment on the death is Guru’s family, who allege that Solar has been keeping them away from the ailing rapper in his final days, as well as failing to notify them of his health decline within a reasonable window of time. This allegedly got even worse after his siblings had visited him while he was in a coma, later leaking news of his health crisis to the public. “Since the information leaked,” Guru’s nephew, Justin Nicholas Elam-Ruff, said in a video posted to YouTube, “Solar has completely cut us off. My family has no way of knowing what is going on with Guru’s situation. … The doctors and the staff at the hospital will not discuss any information with Guru’s family.”