Wilms tumor
Wilms Tumor
Introduction
Wilms Tumor or otherwise nephroblastoma is a rare form of kidney cancer that is often diagnosed on children more than on adults. The medical condition was first identified and described by the German surgeon named Dr. Max Williams (1867-1918) (Nordqvist, 2010). Although the tumor is often the most malignant among children particularly during the age three to four years old, but there are cases where both kidneys are affected. In the United States, there are about 500 cases of Wilms tumor reported, with almost 90% of the sufferers survive at least five more years (Nordqvist, 2010). Even though the outlook for Wilms tumor is good due to the availability of complex medication and treatment approach, the min concern about the condition is that the target population of the disease are mostly children, which makes it most concerning. The importance of determining the symptoms, treatment, and other information about the disease will help care professionals including nurses in addressing the condition particularly among children.
Epidemiology
There are approximately 500 adolescents and children in the United States are diagnosed with Wilms Tumor with at least one diagnosed of the condition in the 20-year old population each year (Breslow et al., 1993). Statistics have not changed since the last 21 years not only in the United States, but also globally. Occurrences of the disease are found to be more prevalent among female and black children as compared to male and white children. However, data that is more recent suggests that an occurrence of the disease is equally prevalent among male and female children regardless of white or black (Breslow et al., 1993). Furthermore, it was found that children of Asian descent appeared to have lower occurrence of the disease than those of white and black children. This is because children of Caucasian descent have higher incidence of IGF2 loss imprinted in renal lesions precursor.
The tumor occurs commonly in the first two to five years of life as evident in unilateral cases of males at a mean age of 42 months as compared to females at a mean age of 47 months (Faranous et al., 2009). There are about 100% of the patients appeared to have metastatic disease during presentation with common instances of regional lymph nodes in the lungs, bones, and liver by 80% (Faranous et al., 2009). With regards to risk factors, Wilms tumor is more prevalent in children born abnormalities such as Hemihypertrophy, Aniridia, Hypospadias, and Undescended testicles. Furthermore, the disease is also likely to occur as part of rare syndromes such as Denys-Drash syndrome, Beckwith-Wiedemann syndrome, and WAGR syndrome.
Definitions and Background Data
Figure 1 Composite CT and Ultrasound images (Gamma.wustl.edu, 2006)
Figure 2 Anatomy of female urinary system (Winslow, 2010)
Figure 3 A child diagnosed with Wims tumor (facultyofmedicine1.blogspot.com, 2010)
Figure 4 Diseection of a Wilms tumor infected kidney (7sib.ir, 2010)
Therapies geared towards Wilms tumor have evolved with the help of the studies conducted by the National Wilms Tumor Study Group. Through the number of studies conducted by the group, prognostic factors were identified and with the help of the data collected from the study, treatment towards the disease were tailored according to the needs of the condition and identified factors. Based on the evidences, the re-lapsed free survival of the children diagnosed with the tumor has found to exceed 91% (Shamberger, 1999). Factors attributed to the prognostic imports were deemed less significant as more effective treatment regimes were developed. With the use of nested case-control study design, 182 matched controls were found (Shamberger, 1999). The factors found was analyzed for its associated with relative risks including the calculated made, which determined 95% confidence intervals (Shamberger, 1999;Erhlich et al., 2009). Children’s survival during local recurrence was poor with at least two years of survival rate was found, but with the help of new findings in research, the survival rate was increased by 43% (Shamberger, 1999;Erhlich et al., 2009). The data attributed to the findings in this report were obtained from previous research.
A five-year old white female visited the Pediatric department of King’s Cross hospital to see the pediatric doctor because of complains of fever, occasional coughing and lack of activity for more than six days. The mother of child stated that the little girl feels tired and refuses to eat anything. After an initial diagnosis, the patient was found to have suffered with rhinorrhea leading to loss of appetite, the parents administered the child with acetaminophen for the fever, but there seemed to be no response. No other medications were tried and the mother being the historian has denied instances of urinary difficulty, diarrhea, or constipation. Furthermore, the child has passed all preliminary tests and medical history revealed no indications of other illness even after birth and that the little girl was able to complete her immunization. The family medical background also has no indication of major illnesses. The pediatrician is worried about the condition of the child given the patient’s weakening state, but without existence of any common illness. The doctor ordered a full medical exam including an MRI to determine the cause of the problem.
Pathophysiology
Most of nephroblastomas are unilateral; they are usually encapsulated and do not typically cross the abdomen midline. Metastasis usually occurs in the lungs, but a rapture of Wilms tumor is likely to put the patient into greater risk of peritoneal dissemination and hemorrhage. In such cases, surgical intervention would be necessary because removing the fragile tumor is imperative to the survival of the patient. The tumor can be identified into two separated based on pathologic characteristics. The first one is favorable prognostic group, which encompasses a well-developed component and the second one is called anaplastic, which contains poorly developed cells or diffuse anaplasia.
The kidney is a pair of peritoneal structure with the left kidney that is normally more superior position than the right and the upper poles normally more oriented posteriorly and medially than the lower poles (Cheuck, 2013). The kidney’s primary function is to filter body fluids with metabolic waste products such as ammonium and urea. It also includes stimulation of the red blood cells production, regulation of electrolytes, and acid-base balance. Glucose and amino acids reabsorption is also part of the kidney’s function including vitamin D activation, calcitriol, and erythropoietin. The existence of Wilms tumor changes the structure and function of the kidney because of hyper filtration, which eventually leads to renal damage. In addition, the patient experiences non-tender abdominal mass due to tumor tissues building up in the kidney.
Clinical Presentation
Physical examination will reveal palpable abdominal mass with utmost consideration to WADR syndrome associated to aniridia, malformation, genitourinary, and signs of overgrowth. Differential diagnosis on the other hand should take into consideration mesoblastic nephroma, clear cell sarcoma, nonmalignant mass, renal cyst, renal thrombosis, rhabdoid tumor, renal cell carcinoma, dysplastic kidney, and renal hemorrhage.
Disease Progression
Primary tumor increase in size is prevalent during the preoperative chemotherapy. The tumor is significantly small at diagnosis and more often during stage III is associated to high risk histopathology. Generally, the progression of localized Wilms tumor is often difficult to determine during preoperative chemotherapy stage. However, increasing tumor size often has poor event-free survival.
Diagnostic Procedures
Wilms tumor is diagnosed through physical exam and medical history. If symptoms and signs of the disease become imminent, clinicians would have to conduct, medical history investigation to determine the time the tumor is in existence. The key findings can be found in size abnormalities in the abdomen and increased blood pressure. Blood and urine samples will be collected for laboratory testing. Imaging tests is paramount in determining the size and position of the tumor such as MRI, X-Ray, and ultrasound. In most cases, Computed tomography is required to get a clear picture of the tumor and areas in the kidney it has invaded. Contrast solutions will be injected or fed to the patient to get a clear outline of the tumor. However, in order to specifically determine the tumor, kidney biopsy/surgery is needed to acquire cytology specimens for cancer and testing biopsy.
Treatment
Specific medications can be taken to reduce tumor size and eliminate the tumor cells. Treatment of Wilms tumor depends on its stage. Stage I with tumor size less than 550 grams, chemo medication such as actinomycin D and vincristine is likely to work. In the even of surgery for patients older than two years old, the medication doxorubicin can also be administered as along with radiation therapy. Stage II with favorable histology can undergo standard surgery chemo treatment along with similar medication stated for Stage 1. Unfavorable histology with focal anaplasia radiation therapy is required over the course of several weeks followed by a chemo for six months using the aforementioned medications. Widespread analapsia on the other hand will require more intense chemotherapy using medications doxorubicin, etoposide, carboplatin together with mesna and cyclophosphamide. The higher stage tumor will require surgery, radiation, and chemotherapy. However, chemo will need to come first before surgery in order to shrink the tumor followed by the aforementioned medications (cancer.org, N.D.).
New trends in care and treatment such as the use of multidisciplinary therapy followed by randomized trials. Furthermore, management of the disease develops protocols with neoadjuvant chemotherapy followed by nephrectomy and chemotherapy (Shortliffe, 2008). On the other hand, the National Wilms Tumor Study Group developed protocols suggests nephrectomy followed by chemotherapy regimen customized according to the pathologic tumor stage. The treatment and management goals of Wilms tumor aimed to reduce morbidity and ensure higher survival rate. Complex treatments are being developed to address complications including cardiomyopathy, increased risk, and renal failure. However, the role of laparoscopic surgery as primary management approach to Wilms tumor remained limited (Shortliffe, 2008).
References
7sib.ir (2010). Dissection of a Wilms tumor infected kidney [Photograph]. Retrieved from http://www.7sib.ir/fa/مقاله/تومور-ویلمز
Breslow, N., Olshan, A., Beckwith, J. B., & Green, D. M. (1993). Epidemiology of Wilms tumor. PubMed, 21(3), 172-81.
Cancer.org (n.d.). Treatment by type and stage of Wilms tumor. Retrieved November 27, 2013, from http://www.cancer.org/cancer/wilmstumor/detailedguide/wilms-tumor-treating-by-stage
Cheuck, L. (2013, October 4). Kidney Anatomy. Retrieved November 27, 2013, from http://emedicine.medscape.com/article/1948775-overview
Ehrlich, P. F., Ferrer, F. A., Ritchey, M. L., Anderson, J. R., Green, D. M., Grundy, P. E., . . . Shamberger, R. C. (2009). Hepatic Metastasis at Diagnosis in Patients With Wilms Tumor is not an Independent Adverse Prognostic Factor for Stage IV Wilms Tumor. Transactions of The Meeting of The American Surgical Association, 250(4), 642–648. doi:10.1097/SLA.0b013e3181b76f20
Facultyofmedicine1.blogspot.com (2010). A child diagnosed with Wilms tumor [Photograph]. Retrieved from http://facultyofmedicine1.blogspot.com/2010/10/what-is-your-medical-diagnosis-55.html
Faranous , M., Bahoush , G. R., Mehrv , A., Hejaz , S., Vossough, P., Hedayatia , A. A., Rahiminejad, M. S., Seigha, F., Ghorba , R., & Ehsani , M. A. (2009). Wilm’s Tumor: Epidemiology and Survival. Medwell Journals, 4(1), 86-89. Retrieved from ISSN: 1815-8846
Gamma.wustl.edu (2006, June 16). Diagnosis: Neuroblastoma [Composite CT and Ultrasound images]. Retrieved from http://gamma.wustl.edu/mb002te183.html
Nordqvist, C. (2010, May 8). What Is A Wilms' Tumor? What Causes A Wilms' Tumor? - Medical News Today. Retrieved November 27, 2013, from http://www.medicalnewstoday.com/articles/188130.php
Shamberger, R. C., Guthrie, K. A., Ritchey, M. L., Haase, G. M., Takashima, J., Beckwith, J. B., . . . Walsh, P. C. (1999). Surgery-Related Factors and Local Recurrence of Wilms Tumor in National Wilms Tumor Study 4. Journal of Urology, 229(2), 292–297. doi:10.1016/S0022-5347(05)68371-1
Shortliffe, S. G. (2008). Management of Wilms tumor: current standard of care. PubMed, 5(10), 551-60. doi:10.1038/ncpuro1218
Winslow, T. (2010). Anatomy of a female urinary system [Illustration]. Retrieved from http://www.cancer.gov/cancertopics/pdq/treatment/wilms/patient/
Øra, I., Tinteren, H. V., Bergeron, C., & Kraker, J. D. (2007). Progression of localised Wilms’ tumour during preoperative chemotherapy is an independent prognostic factor: A report from the SIOP 93–01 nephroblastoma trial and study. European Journal of Cancer, 43(1), 131–136. doi:10.1016/j.ejca.2006.08.033
