Cancer Staging ?

Yeah...I've invoked the "y" thing in my reports.

 

It's not new.

Well, we get quite a few cases from patients who have received chemo prior to surgery. Sometimes I don't get the point of "restaging" patients cuz in some cases preop chemo actually does something. I don't see the point of downstaging patients and making a big deal out of it. But I will invoke the "yp" restaging. I don't know what significance this has for the clinicians as rarely the patient is cured by preop chemo/rad.

I dunno if this is new. Some of my attendings like the "yp" restaging whereas others don't bother to write down the stage for these patients. I can understand both perspectives. Look, the patients have been staged prior to receiving therapy. It's not like treating them is going to change their stage at that point in time. Either the chemorad works (partially) or it doesn't. The whole exercise can be kinda silly if you ask me.

 

They use ypT here for esophageal, primarily. I guess rectal cancers too but I haven't personally had to sign one of those out. We don't use it for bladder because they usually use the highest clinical or path stage that has been attained before. For nodes, we just say "nodes with therapy related changes, probably treated metastatic carcinoma, no viable tumor" or something to that effect.

 

I don't. I give them pathologic (p) staging. I leave it to the clinicians to figure out the clinical staging. With the disturbing lack of clinical information I usually get, I can't be chasing down every damn surgeon or oncologist in order to nail down the exact clinical stage of a given tumor. Thats their jobs.

It reminds me of what Keith Richards said when asked why he doesn't sing more during Rolling Stones concerts. His answer: "What would Mick do?"

 

Hrmmm Not sure I would go that far (the "no viable") unless I saw lots of necrotic tumor cells in the mucus. Otherwise, if I just saw lots of mucus and no cells, I would be concerned that viable tumor cells were still there.

 

Yeah, I dunno either. I think they basically treat it the same way though.

 

Absolutely! I had a case like that but I was able to see residual tumor cells so the pankeratin was not warranted. But especially with signet ring cancers, it's amazing what will light up on a keratin stain. I've seen deeper invasion in the tumor sections and a doubling of positive lymph nodes! Crazy stuff man.

 

The whole area of assigning TNM staging after therapy is controversial. although we assign a y for cancers treated with neoadjuvant therapy, the data regarding the clinical importance of that with regard to prognosis is just emerging.
Most commonly, rectal cancers (and esophageal tumors) that are T3 or worse clinically (usually by EUS) are the ones that get the neoadjuvant therapy, so you can end up with anything from a T1 to T3 in the resection specimen. It's ok to assign the stage based on what is in the resection specimen even if it is different than the pre-op clinical stage (the clinical stage will determine post op treatment if higher than the final pathologic stage). Lymph nodes with mucin pools in the post-neoadjuvant setting imply the presence of mets (no need to do keratin stains, particularly if the original tumor was a straightforward colon CA and not a SRC carcinoma) and most cancer centers don't even bother to assign an N stage based on their presence. (if mucin pools in a couple nodes are all that are left, we just say it in a sentence without a formal N stage).
Although more data may come out later and change everything, the most important factor that predicts outcome after neoadjuvant therapy is the tumor response. We have started including that info in our reports in accordance with a recent publication that correlated the "grade" of tumor response with outcome. Can give you the reference if interest extends beyond this thread.

 

Hey man, thanks for recommending Essentials of Anatomic Pathology. I just scored my copy yesterday and it's f****n' awesome. It's what I was hoping Differential Diagnosis in Surgical Pathology would be.

One of the reviews on Amazon states that it's "dry." No sh!t! It's a huge outline of anatomic pathology! Not exactly a taut psychological thriller, but I can tell it's going to be my constant companion for at least 3 years.

 

Interesting info. I’d be very interested to know if there is a standardized way to grade tumor reponse. To me it makes sense to have three grades:
- Complete response (no residual viable carcinoma identified)
- Partial response (microscopic foci of residual carcinoma identified)
- No significant response (residual carcinoma identified grossly)
Does anybody know if most people grade subjectively (as above), or use more objective criteria e.g. percentages, etc…?

 

It is somewhat standardized for sarcomas, post treatment. Every report here has a template which includes percent of necrosis (as a gauge on therapy effectiveness). And as to your three grade system, this is defacto how most post treatment tumors are signed out. The diagnostic line generally refers to what is left, be it most of the tumor, or microscopic foci, or just mush.

 

Yes. most common is a 5-tier system, although some people advocate for a 3-tier system. one paper in J Clin Oncol. 2005 Dec 1;23(34):8688-96 defines as follows:
Tumor Regression Grade (TRG)
TRG 0= no cellular response and no fibrosis
TRG 1=morphologically unaltered tumor mass
TRG 2=regression less than 50% of total mass
TRG 3=regression more than 50% with fibrosis outgrowing the tumor mass
TRG 4= no viable tumor cells
Five-year disease-free survival (DFS) after CRT and curative resection was 86% for TRG 4, 75% for grouped TRG 2 + 3, and 63% for grouped TRG 0 + 1 (P = .006).
Seems to me there isn't much difference between TRG 0 and TRG 1 with regard to definition and the outcomes are similar. Improved longterm outcome is associated with progressively better tumor response. Big surprise

 

can mucus become cancer?

 

Some AdenoCAs can produce significant mucus, and can sometimes be hard to identify cancer cells in the mucus. So no mucus can't become cancer. It is more like "where there is smoke there is (possible) fire"...

If that was sarcastic, the my response should have been "yeah, smart guy"!