Saggy skin after having treatment for throat cancer 6yrs ago. Is there anything that can be done for saggy neck?

I am sorry to hear of your concern. But I am happy to hear you overcame cancer. It is best to begin by consulting with a board-certified surgeon in-person. The presence of banding down the front of the #neck, and, amount of excess skin and condition of your skin are among some factors which determine if you are a #candidate for #rejuvenating the neck. Chin deficiency with the neck and jawline are also taken into consideration. A weak #chin implies a lack of chin support for the skin along the neck line. As a stand-alone procedure, chin augmentation can be performed in the office under local #anesthesia. For individuals with signs of aging in the neck, a chin implant added to one of the recommended procedures above, will provide optimal results.
Patients who desire facial rejuvenation that is affordable, quick, and effective should also consider the Lite-lift™. Like the Life-Style™ facelift, this is a modified facelift, individualized for each patient, that can be performed in the office with a local anesthetic and improve signs of aging around the neck, jawbone and lower face. These procedures are not "Thread-lifts" or "String-lifts". We do not use the "barbed" sutures employed in these other lifting operations. The Lite-lift™ uses longer lasting techniques that are discussed below. Because the incisions are limited, there is less bruising, swelling and healing time for most patients. Many patients can be back to work in one to two weeks looking rested and more youthful.
A board certified plastic surgeon should evaluate both your anatomical features and aesthetic goals to suggest which procedure best suits your needs. In some cases there may be more than one option to choose from. If you are not a candidate at the time of your #consultation, your board surgeon can recommend non-surgical alternatives to address your concern. 

It is common for the neck to age in advance of the face, signs of which can manifest in early to mid 40s. The underlying mechanisms for neck aging include laxity and descent of the platysma muscle, excess fat, and/or skin excess. A surgical neck lift is the only modality fully capable of addressing all of the components of neck aging and would certainly give you an excellent correction of the problem.

Hello and thank you for your question.  The
best advice you can receive is from an in-person consultation. In some patients, a necklift can help to tighten sagging neck skin.   Make sure you specifically look
at before and after pictures of real patients who have had this surgery
performed by your surgeon and evaluate their results.   The most
important aspect is to find a surgeon you are comfortable with. I recommend
that you seek consultation with a qualified board-certified plastic surgeon who
can evaluate you in person.
Best wishes and good luck.
Richard G. Reish, M.D.
Harvard-trained plastic surgeon