Tuesday, February 27, 2007

SPN

79 year old female non smoker presented with hypercalcemia and a low PTH. She was pan-ct'd and all that came up was this SPN in the RML:

It's size is about 7 mm. Of note, the CT slices were 7 mm.
How would you proceed?

13 comments - CLICK HERE to read & add your own!:

Anonymous said...

How high is calcium ? If she is on HCTZ or Vit D. DC those.
Send PTHrp, alphos, calcitoriol, SPEP/UPEP, TSH, ACTH stim, ILGF-1. And change the title to Endocrine Round Table.
Lung nodule may be a red herring.

Jennings said...

The calcium was 20. How would you proceed with w/u for the nodule? Lets say the PTHrp was not detected or that it was high. Would management of the SPN be different from a patient without hypercalcemia?

Jennings said...

In other words, does the hypercalcemia change your pretest probability for a lung cancer (assuming other causes suchb as primary hypercalcemia etc, are ruled out )

Anonymous said...

I don't think it would change the w/up. Unless you had a large lung mass with the hypercalcemia...

Anonymous said...

Regardless of the hypercalcemia, unless there's a contraindication, mediastinal LAD, or extrathoracic disease suspected on PET, this nodule should come out.

The question really is whether the hypercalcemia is related to the nodule. So while treating the hypercalcemia you are looking for it's etiology and resection of that nodule would be part of that as well.

Anonymous said...

Calcium level that high usually means malignancy somewhere. And if a cancer causing hypercalcemia, it is usually advanced.
So it seems unlikely that the nodule is lung cancer although it is not impossible. Look for other sites first such as breast, head and neck, GI, myeloma, renal etc. Would consider lung bx only after other possibilities are excluded.
Given the size of nodule, hypercalcemia may slightly, increase my pretest probability that the lung nodule is malignant but not much.

Anonymous said...

A PET would help detect any extrathoracic malignancy. If the PET shows no other disease, then that nodule does not need a biopsy, it needs to be resected.

Certainly, if any malignancy can be found elsewhere, I agree in holding off on resecting the nodule. But, if definitive evidence of cancer is not found elsewhere, I think the lung nodule has to be considered malignant until proven otherwise.

Jennings said...

If you plug her numbers into a SPN calculator (I used http://www.chestx-ray.com/SPN/SPNProb.html), the probability for cancer is 21%.
Incidentally, it turns out that the PTH was 187 (high), not low as I had originally been told. Her CT was done in December, so her visit with me brings us to about 3 months so I elected to repeat the CT. If not decreased, she's be referred for resection. Would anyone still just follow it?

Anonymous said...

Are you sure that her calcium was 20? If that is the case, she should be admitted. If cacium is borderline high, given high PTH, most likely diagnosis would be primary hyperparathyroid which is common in the elderly.

Anonymous said...

I agree that, with the elevated PTH it primary hyperparathyroidism is probable, as paraneoplastic syndromes and bony metastases will typically have low PTH levels. In that light, the SPN is a bit less concerning--however a 21% probability is still not very reassuring. So, I'd still do the PET, if it's + it needs to come out, if negative, then I'd consider it a grey zone.

Raj said...

Being 79yrs old makes malignancy more likely.
Her hypercalcemia should be evaluated for other causes and no cause is identified then , go for tumor.
Fleschner Society guidelines says for SPN< 7mm and low risk patient -follow up with repeat CTscan in 3 months. PEt is usually less sensitive for tumor size less than 10 mm and so is Solitory tumor CT protocol

Jennings said...

She was indeed admitted for that Ca of 20...

Anonymous said...

The purpose of a PET in this patient would be to look for evidence of extrathoracic disease to: 1) Facilitate biopsy and 2) Exclude stage 4 disease.

If the PET is negative, the nodule should be resected.