The patient is a girl of 5 years, weight 16,7 kg, height 114 cm. Her parents report that the patient had a growth deficit due to cow’s milk intolerance at 9 months, had her adenoids removed in ----- and she was diagnosed with a bilateral inguinal hernia during her last hospitalization in -----. The patient was brought to the emergency room on ----, ----- due to occasional left abdominal swelling.

An ultrasound showed the presence of a solid mass adhered to the top of the left kidney. After being transferred to “______” Hospital in ____, the patient had a Total Body CAT scan with contrast medium, a chest x-ray and a range of blood chemistry tests (in her urine: Vanilmandelic acid 7.2 and homovanillic acid 12.5), which allowed a diagnosis of stage I Wilms’ Tumor (the mass was contained and no metastases were found).

On -----, -----, the patient was transferred to the Oncology Unit where a catheter was installed to begin chemotherapy in accordance with the International Pediatric Oncology regimen: 4 sessions, two of which with Vincristine 1 mg and Actinomycin D 750 mcg, and 2 with only one medication prior to surgery in week 5, and then 5 more weeks of chemotherapy.

The patient’s father would like to know whether you can confirm the diagnosis and stage of the pathology, the recovery rate at this stage, whether you agree with the chemotherapy treatment prior to surgery, or if it would be best to have the surgery first in order to establish the exact histology of the tumor. The patient’s father would also like to know whether a histology test after chemotherapy would be affected by the medications and result in erroneous assessment of the type and/or degree of the condition, if the first positive sign is a reduction of the mass following chemotherapy, and if you believe that further diagnostic and/or laboratory tests should be carried out in addition to those in the appended list.

Lastly, the patient’s father would like to know whether any lifestyle, hygiene and diet requirements should be followed during and after treatment, and whether surgery should be performed by a surgical team or a urology team.


The expert’s opinion
For Medical Opinion Thank you for the referral and the copy of the medical records for the patient. This is a second opinion based on the attached clinical information. I have not performed a clinical examination of the patient. This second opinion has been requested on behalf of the patient by Medical Opinion.

The patient is a 5 years old girl with a suspected diagnosis of stage 1 Wilms´ tumor. Her history includes failure to thrive at 9 months of age due to cow´s milk intolerance, and adenoidectomy in -----. The patient was also diagnosed with bilateral inguinal hernia during her hospitalization in -----. The current girl´s presentation was an incidental finding of left abdominal swelling. Laboratory tests included complete blood count, platelet count, renal function tests, liver function tests, serum calcium and urinalysis were all normal.

The reports of the abdominal US, total body CT together with normal values of catecholamine metabolites (which rules out neuroblastoma) are in favor of stage 1 Wilms´ tumor. Looking carefully at the attached images, I do agree with the radiologist that the tumor staging is consistent with stage 1. Nevertheless, although there is a high probability that the mass is a Wilms´ tumor, the definitive diagnosis and staging could be defined only after a pathological examination of the mass and the lymph nodes.

To assess the actual pathology, the girl should have undergone surgery prior to chemotherapy. This attitude represents the American oncology system that was adopted in the late 1960s followed by 5 large studies looking for the optimal treatment for the different stages of Wilms´ tumor called National Wilms´ Tumor Study (NWTS). According to NWTS, the initial treatment in similar cases should include surgery, followed by chemotherapy after a definitive diagnosis and staging were performed. NWTS investigators recommended immediate nephrectomy because the administration of prenephrectomy chemotherapy may be associated with: 1. administration of chemotherapy to a patient with a benign disease; 2.administration of chemotherapy to a patient with a different histology type of malignant tumor; 3. modification of tumor histology; and 4. loss of staging information.

Conversely, in the early 1970s, a European group called the International Society of Pediatric Oncology (SIOP) was established. SIOP have also conducted large prospective protocols in which preoperative chemotherapy was followed by surgery. SIOP hypothises that this approach usually results in tumor shrinkage, reducing the risk of intraoperative spill (Lemerle et al., 1976). It is also postulated that the neoadjuvant therapy will treat micrometastases, leading to a more favorable stage distribution at the time of surgery. Finally, SIOP have claimed that the risk of non cancerous lesion is only 1%.

Although the National Wilms´ Tumor Study Group and the International Society of Pediatric Oncology differ philosophically regarding the merits of preoperative chemotherapy, outcomes of patients treated with either up-front nephrectomy or preoperative chemotherapy have been excellent.; children with stage 1 and a favorable histology have 4-5 years event free survival that approaches 90%.

According to SIOP 9 the patient should receive 4 weeks of prenephrectomy treatment with vincristine and dactinomycin. However, for selected patients, shorter courses of vincristine/dactinomycin or vincristine alone show equivalent results compared to current regimens (D´Angio, Curr. Opi Urol, -----).

In my opinion no further diagnostic or laboratory tests are currently needed in addition to those that have been already done.

Regarding lifestyle, hygiene and diet during and after treatment.

The chemotherapy administered to the patient usually does not cause severe side effects. Thus, we do not limit diet of any kind. Nevertheless we instruct our patients´ parents to wash carefully fresh fruits and vegetables, and to try to avoid pastries in restaurants during chemotherapy. In cases where the white cell counts are going down we recommend to avoid exposure of the child to people, but usually the patient does not need to be in isolation.

We also do not recommend performing physical effort 6-7 weeks after surgery.

Surgery should be performed by the most experienced team at the patient´s institution either by the surgeons or the urologists; I would also recommend considering to fix the patient´s hernias at the time of the nephrectomy.

If we can be of any further help to you, please contact through mdical-opinion

I wish the patient have fast and complete recovery,

Sincerely yours,

Dr. ______________