user19338: Human is subject to very short life span, sickness and death according to Buddhism Cosmology.
Suicide is somehow wrong livelihood in Buddhism.
If one very old age and with the issues below.

Diagnose with late stage of cancer
2 more operations for kidney failure and heart disease
Have financial issues and need public donation for the above 2.

If under this situation, the patient decided to end the life peacefully by taking pain killer that approved doctor. Patient wants to minimize the suffering and minimize the spread of negativity to surrounding.
Does this consider wrong livelihood ?
What this patient should do?
I saw a Buddhism teaching video before, if one suicide will decent to deepest level of hell. So, does this scenario applicable?
I understand only certain monk can do similar kinda suicide.
Anagami monk ( 3rd level attained ) or Arhant monk ( 4th level attained )

user10918: Killing oneself does not stop one to be born again to another form of life, according to Buddhism. It does not stop the fruit of karma. Suicide will only change the form of suffering you may have. If you don't want whatever illness you currently have and want to stop it, then you will still get the similar kind of suffering after the death you committed, but in another form of life.
What the patient should do? As a buddhist, he/she may try to renunciate, accept whatever happen to him/her as manifestation of the law of karma. Doing meditation may support him/her to deal with that situation.

user254: 
the patient decided to end the life peacefully

I'm not one to talk but maybe the better decision would be, "the patient decided to live the life peacefully".
A "decision to end life" sounds like "killing" -- which is not recommended in the canon, and is not the same as "dying".
Even the phrase "a peaceful suicide" in the title sounds like "describing the advantages of dying" which is a kind of action that would be considered an "offence of defeat" if done by a monk.

What this patient should do?

The canon says something about what makes a patient easy to care for -- see AN 5.123.

minimize the spread of negativity to surrounding

My wife allowed people (including me) to care for her when she was dying of cancer:

Followed doctors' prescriptions, including pain killers but no more than prescribed
Advised us on (i.e. helped us plan) what we should do after she was gone
Thanked the doctors for "saving her life"
And, as I said, allowed us to care for her

I guess that could be called a peaceful death -- more importantly an "end of life", focussing on the "life" not on the "end", i.e. on her and other people's intentions and behaviours while she was alive and with us.
If you really want to minimize people's suffering, the way to do that may be to be "enlightened" (and with them).

user21955: Better to invite monks to continuously teach, good householder, as there are a lot of possibilities to gain path toward real peace once having gained a human existance, which isn't sure at all if letting such change go. Killing, call for, encourage, agree, approve, assist... that's all killing, taking live, with it's hard consequences... short life, pains misserable existances... The wheel of suffering doesn't end by cutting of life but by seeing and understanding cause Dukkha clear, and even one short teaching could be enough.
Much place to make huge good deeds here, so good to waste no time. Death is for sure, the Gems to meet not.

19338: <p>Human is subject to very short life span, sickness and death according to Buddhism Cosmology.</p>
<p>Suicide is somehow wrong livelihood in Buddhism.</p>
<p>If one very old age and with the issues below.</p>
<ol>
<li>Diagnose with late stage of cancer</li>
<li>2 more operations for kidney failure and heart disease</li>
<li>Have financial issues and need public donation for the above 2.</li>
</ol>
<p>If under this situation, the patient decided to end the life peacefully by taking pain killer that approved doctor. Patient wants to minimize the suffering and minimize the spread of negativity to surrounding.</p>
<p>Does this consider wrong livelihood ?</p>
<p>What this patient should do?</p>
<p>I saw a Buddhism teaching video before, if one suicide will decent to deepest level of hell. So, does this scenario applicable?</p>
<p>I understand only certain <a href="https://www.youtube.com/watch?v=f05QeUJbmiI" rel="nofollow noreferrer">monk</a> can do similar kinda suicide.
Anagami monk ( 3rd level attained ) or Arhant monk ( 4th level attained )</p>
 10918: <p>Killing oneself does not stop one to be born again to another form of life, according to Buddhism. It does not stop the fruit of karma. Suicide will only change the form of suffering you may have. If you don't want whatever illness you currently have and want to stop it, then you will still get the similar kind of suffering after the death you committed, but in another form of life.</p>
<p>What the patient should do? As a buddhist, he/she may try to renunciate, accept whatever happen to him/her as manifestation of the law of karma. Doing meditation may support him/her to deal with that situation.</p>
 254: <blockquote>
<p>the patient decided to end the life peacefully</p>
</blockquote>
<p>I'm not one to talk but maybe the better decision would be, &quot;the patient decided to live the life peacefully&quot;.</p>
<p>A &quot;decision to end life&quot; sounds like &quot;killing&quot; -- which is not recommended in the canon, and is not the same as &quot;dying&quot;.</p>
<p>Even the phrase &quot;a peaceful suicide&quot; in the title sounds like &quot;<a href="https://buddhism.stackexchange.com/a/7808/254">describing the advantages of dying</a>&quot; which is a kind of action that would be considered an &quot;offence of defeat&quot; if done by a monk.</p>
<blockquote>
<p>What this patient should do?</p>
</blockquote>
<p>The canon says something about what makes a patient easy to care for -- see <a href="https://buddhism.stackexchange.com/a/44932/254">AN 5.123</a>.</p>
<blockquote>
<p>minimize the spread of negativity to surrounding</p>
</blockquote>
<p>My wife allowed people (including me) to care for her when she was dying of cancer:</p>
<ul>
<li>Followed doctors' prescriptions, including pain killers but no more than prescribed</li>
<li>Advised us on (i.e. helped us plan) what we should do after she was gone</li>
<li>Thanked the doctors for &quot;saving her life&quot;</li>
<li>And, as I said, allowed us to care for her</li>
</ul>
<p>I guess that could be called a peaceful death -- more importantly an &quot;end of life&quot;, focussing on the &quot;life&quot; not on the &quot;end&quot;, i.e. on her and other people's intentions and behaviours while she was alive and with us.</p>
<p>If you really want to minimize people's suffering, the way to do that may be to be &quot;enlightened&quot; (and with them).</p>
 21955: <p>Better to invite monks to continuously teach, good householder, as there are a lot of possibilities to gain path toward real peace once having gained a human existance, which isn't sure at all if letting such change go. Killing, call for, encourage, agree, approve, assist... that's all killing, taking live, with it's hard consequences... short life, pains misserable existances... The wheel of suffering doesn't end by cutting of life but by seeing and understanding cause Dukkha clear, and even one short teaching could be enough.</p>
<p>Much place to make huge good deeds here, so good to waste no time. Death is for sure, the Gems to meet not.</p>
