Hello XXXXX,

Thanks for writing in.

From the information provided, I understand you are a 40 year old lady with a history of a mass lesion involving your tibia since 6 months (there is no mention of direct bone involvement by you though). Subsequent MRI scan of the affected region shows that the mass is presently described as septated, elongated and extending to involve intramuscular septation measuring 12.5 x 2.4 cms.

Inflammation and neoplasia are the main differential diagnoses of a mass lesion involving bones and muscles. From what you have said, this cannot be definitely categorised as a cancer at the moment. There are many features peculiar to cancer and some of them can overlap with inflammatory lesions. If the bone is not at all involved, the possibility of soft tissue neoplasms needs to be thought of.

As a radiologist, I would like to go through your complete report details (both scans) if possible - to know the previous imaging features and the present ones, to know the interval growth of the lesion.

Even in cancers, there are lesions that are very fast growing, some that are moderately growing and some slow growing benign ones which show cancerous transformation later on. A biopsy from the lesion is most confirmatory to know the process going on within. The entrapment of your peroneal nerve is surely a sign that your condition needs to be investigated thoroughly before pronouncing a diagnosis.

There are many types of pathological tests available and most of them are image guided allowing little error in diagnosis. Some of them are:
1. Fine-needle aspiration cytology/ biopsy (office procedure with small needle put into lesion)
2. Core needle biopsy (office procedure with slightly bigger needle than above put into lesion)
3. Incisional biopsy (office procedure with small XXXXXXX in skin and sampling of tissue into lesion)
4. Excisional biopsy (done for small lesions during surgery)
5. Frozen section and intraoperative cytology (done during surgery)

All office procedures are done under local anaesthesia and image guidance making it an almost pain free procedure.

Once the pathological sample is taken, it is sent to the laboratory for evaluation by pathologists.With advances in molecular biology, oncogenetics, imaging techniques, immunochemistry, diagnosis is more accurate these days.

I would suggest that you proceed with your pathological tests and rule out the presence of cancer first. Please do not delay in taking this decision of getting a biopsy done.

Hope your questions have been answered.

Further questions are welcome and please do provide me the details of the type of surgery you underwent as that will help me explain better.

Wishing you good health.

Regards,
Dr Vivek

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Hello XXXXX,
Thanks for writing in again with details of previous MRI.

I will review both reports in simple language for you to understand.

MRI dated 10/12 shows:
The peroneus longus muscle runs below from the calf region to the ankle towards the lateral (outer) part of lower leg. In the report, it is mentioned that there is some watery material within the muscle correlating with your swelling. There is also mention of abnormal uptake of contrast (means some blood flow can be present). Therefore, a tear within the muscle (which was healing at that time) or a soft tissue pathology could not be excluded.

Recent MRI report shows:
An elongated 12.5 cm x 2.4 cm mass in the peroneus longus muscle which has septations (thin partitions). The doctor is sure that it is a mass and not a fluid containing area within the muscle as seen before. This is a change which has taken place over 6 months.
In six months if a fluid contatining area (as in earlier report) becomes a mass or semi solid area, there are many things that come to the mind. It could as well be an inflammation showing changes over time else (rare possibility) it could have transformed into abnormal growth which can again be benign or malignant.

Lets take a round up of the possibilities in your situation keeping both report findings in mind:

1. Muscle contusion or hematomas: This is a situation where the muscle gets torn and bleeding develops. Let me inform you that rarely, an injury is not necessary for such an event to occur. It can happen spontaneously. At first there is bleeding and the blood disintegrated and fluid appearance can be there. Later on there is organized thickening of the blood and since the exuded blood has no where to go, septations develop and can stay that way for some time.
I have seen this happen in one of my own patients and we confirmed it by doing biopsy.

2. Benign tumor: Please remember that few benign tumors can get locally aggressive or may show suspicious changes over time. They can remain benign and show features generally seen in malignant tumors. This needs to be confirmed/ excluded in your case.

3. Malignant tumor: Some malignant tumors start off as a small well defined lesion, more like a benign one. Over a time period there are changes within and it starts infiltrating. Malignant tumors can be treated best when detected early. One should not take chances even when there is a faint doubt of a malignancy.

4. Hemangioma: This is an abnormal mass of small arteries, capillaries and veins through which blood flows and this can slowly grow over a period of time. This is a benign condition with good treatment results.

5. Ruptured or enlarging Baker’s or any cyst with intramuscular extension: This is a benign finding and may not be in your case, but needs to be excluded in any patient presenting as you are.

Hope your questions have been answered.
If you do not have any questions, I request you to please close this thread and post a feedback.

Wishing you good health.

Regards,
Dr Vivek

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Hi XXXXX,

You are most welcome.

I too am hoping the best for you.

Wishing you good health.

Regards,
Dr Vivek

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