Robert L. Ebeling, III.

This is not really a question dealing with cancer or cancer treatment; this would be better posed to an expert in that field.

To be honest, there is little you as a patient can do other than follow any instructions your Radiation Oncologist has given you. The biggest factor in how much dose your eyes get is how the treatment is planned. It would be very reasonable for you to ask your doctor how he or she is planning on sparing your eyes from excess radiation.

I think that depends on what kind of radiation they used to locate and biopsy the growth. If the biopsy was done with ultrasound guidance (most common) there is no radiation involved, and thus no risk. If the biopsy was done in a CT scanner, there is some scatter radiation, but not much. Usually in this case there would only be a very small area that was actually scanned and there is a good distance between the area scanned (armpit) and where the fetus is (low pelvis). While there is no "safe" dose of radiation to a developing fetus, it is likely very, very low if the biopsy was done with CT guidance. If it was, you can request a report on how much radiation was used during that scan and talk to your OB-GYN and/or your Radiation Oncologist (if she has seen one) about how much the fetus actually received and the risks associated with that dose.

The short answer is highly unlikely. While there is indeed some radiation in a mammogram, the dose is quite low at 4mSv and only directed at the breast. To put that in perspective, smoking 1 pack of cigarettes per day for a year would expose your body to ~25mSv. Mammogram devices usually have a stomach shield built into the device, so that plus the distance from the mammogram head would result in a diminishingly low dose to the developing fetus. While there is no "safe" dose of radiation to a fetus, it is unlikely that there was any damage. To be on the safer side, I would ask her OB-GYN what the likely dose was and what to expect, he or she could give a better estimate than myself without knowing the individual mammogram unit, your wife's height, weight, and the gestational age of the fetus.

Stage 4 lung cancer is, by definition, incurable. That is not to say it is not treatable, and chemotherapy is the method of choice. Depending on what type of lung cancer, what mutations is has (if any), the number of sites of metastatic disease, the drugs used for chemo, his symptoms and overall health, his overall outcome and symptoms can be dramatically different.
Without knowing any of the above, the average survival of a Stage 4 lung cancer patient is about 2-8 months, but this is a great question to ask his medical oncologist who could give a much better estimate.

Short answer: Not with only one episode of pneumonia.
Longer answer: We know that chronic irritation of the lung can lead to a type of lung cancer called Squamous Cell, but by chronic, I mean years and years of nonstop irritation. And even then it would have to be in the same location as the irritation. IF the cancer was in the same spot as the pneumonia, the likely answer is that the cancer was there at the time, it just could not be seen because of the pneumonia.

The likelihood of non-cancerous lymph nodes developing into cancer just because they are enlarged is basically 0%. The nodes may be enlarged BECAUSE of cancer, and that alone is a good reason to make sure they go back down after a course of antibiotics, and if they don't you should be checked out and have them biopsied. Depending on the type of cancer (assuming they are cancerous nodes) surgery to nodes may or may not be therapeutic (curative).

If it were me, I would want the PET. It is the best modality we currently have to evaluate the spread of certain cancers (head and neck cancers is in that group). The PET can detect cancer in a lymph node before it becomes enlarged and can detect the spread of cancer to other organs before these areas become symptomatic. The rationale for imaging close after treatment is that ~80% of head and neck cancers that do recur, recur within 2 years after treatment.

Absolutely! This presentation is classic for skin cancer and should be evaluated rapidly.

Depending on the dose and type of radiation, the proximity of the field to his eyes, and the time since the end of his radiation it may have indeed caused some symptoms that can lead to blurry vision. Radiation can cause decreased tear production resulting in dry eyes - this results in your eyes getting blurry faster in between blinking (think of staring at a computer screen for hours). Radiation can also accelerate the formation of cataracts, but this happens several years after the radiation. The only way to know is to ask his Radiation Oncologist how much dose his eyes got and what side effects that dose could cause.

One of the long term effects of radiation therapy is damage to tiny blood vessels that permeate through mucosal tissue, such as that of the cheek, gums, teeth, etc. Since it is these small vessels that bring healing cells and nutrients to the gum and jaw tissue, the ability to heal in that area is reduced. What would be a normal procedure with minimal risk, might result in slow healing or even death of the tissue affected by the dental procedure.
Perhaps the most severe of which is "osteoradionecrosis". This is when the area of the jaw bone that was in the radiation treatment field cannot heal at all from the dental procedure and actually dies. This situation can require special methods to help your body heal such as hyperbaric oxygen or, in some situations, a fairly big surgery to remove part of the jaw bone.

I like to describe the side effects from radiation this way: All the changes are week-to-week changes, not day-to-day changes.
So if you are able to drive yourself to the appointments, you should be able to drive yourself back. In my practice, for breast cancer patients at least, I have not had a single woman yet be so fatigued from the radiation they cannot drive themselves.

Unfortunately, SCLC is an extremely aggressive disease. Your doctors have proposed to you what would be considered the "standard of care", and represents what newer treatments are compared against. Without any treatment the average survival is about 2-4 months; but with combined chemotherapy and radiation, this improves to 18-24 months. Your doctors are also likely to propose "prophylactic cranial irradiation" or PCI. This is treating your brain with radiation, even though you don't have any cancer there, after all the other chemotherapy treatments are completed. It may sound ridiculous, but this has been shown to improve the number of patients surviving at 3 years from 15% to 20%. Thought of another way, PCI will help 1 out of every 4 patients make it to 3 years.
While every patient is unique and there exceptions to every rule, not doing combined chemotherapy and radiation for your SCLC is likely to result in a greatly shortened life.

Without knowing the details of your radiation plan, my first instinct would be to tell you the nausea is unlikely related to the radiation unless your cancer/treatment was in the lower portions of your lung. If this is the case, I would say the nausea should be significantly reduced by 2-3 weeks, and by 8 weeks be gone.

Before I go into what the "seed" treatment is, you should know there are many factors that determine what treatment is the best for your uncle, or if he needs treatment at all. For my answer, I am going to assume: 1. he is in good health (does not have uncontrolled diabetes, heart disease, etc.); 2. he had more than 3 cores on his prostate biopsy show he had cancer; 3. the Gleason score was 6 or 7 (a scale that determines how aggressive prostate cancer is); and his PSA didn't jump from a lower number (say 3-5ish) to 7.2 in under a year.
In this context he has three options available for him: 1. Active surveillance - they will follow his PSA roughly every 6 months to make sure he remains at low risk of it causing him problems, and then treating him when/if the time comes. 2. Surgery with radical prostatectomy. 3. Radiation therapy.
Within the realm of radiation therapy there are two basic types. The most common type is "External Beam". This is where the patient lays on a table and radiation is delivered by a machine that moves around him to deliver radiation. The radiation is very much like an X-ray in that the patient does not see or feel anything during the treatment. The catch here is that for prostate cancer, external beam radiation is delivered daily, Monday thru Friday, for about 9 weeks. The other type, the kind you are talking about, is called "Brachytherapy". This is where there is an actual source of radiation placed inside the patient to deliver the treatment. You can kind of think of brachytherapy as treatment "from the inside out" versus "from the outside in" as would be the case in external beam treatments. The "seeds" you mention are actual pieces of radioactive material that are placed in the prostate to treat the cancer. This is typically done in the operating room under anesthesia and the Radiation Oncologist puts many needles into the prostate and drops the radioactive "seeds" into place. Once the seeds are in place, they give off their radiation around a very small area over a period of time and eventually decay to where they no longer give off any meaningful radiation. These seeds are permanent and left in the prostate. Here the treatment (at least from your uncle's involvement) is really only one day, rather than the roughly 9 weeks of external beam.
Each of the radiation treatment options has it's own set of side effects that is beyond the scope of this reply, but it is important to talk to the Radiation Oncologist about the pros and cons of the two treatments.