EFFICACY OF SEQUENTIAL BCG AND MITOMYCIN VERSUS MITOMYCIN ALONE FOR TREATMENT OF SUPERFICIAL BLADDER CANCER

A study to compare the efficacy and local toxicity of combining anticancer drugs immunotherapy and chemotherapy (Sequential BCG and mitomycin c) versus mitomycin alone in the treatment of superficial bladder cancer after complete transurethral resection. The study was designed as a prospective study done in Al-hussain Teaching Hospital in Thiqar from July 2007 to August 2010. After transurethral resection and multiple biopsies, eighty-three patients (62m, 21f) from 38-75 years old, suffering from primary superficial (Ta-T1) TCC of the bladder, were randomly assigned to receive intravesical instillations of Mitomycin C (MMC) alone for 41 patients, and the sequential BCG and Mitomycin c, for 42 patients (81 mg BCG infused over 120 min once a week for 2 weeks, followed by 40 mg Mitomycin c once a week for four weeks. The patients evaluated for complications and recurrence and progression rate, they have follow up cystoscope every 3 months for the 1st year then every 6 months for the 2nd year and then yearly . Mean follow-up time was 36 months. The main object of the study were evaluation of recurrence and progression rate and estimate the safety with evaluation of subjective and objective side effects and clinical complications. Of the 83 randomly assigned patients, the analysis demonstrated a significant statistical difference in the recurrence rate. Patients assigned sequential BCG and Mitomycin c had lower recurrence rate 16.6 % (7 patients) versus 29.2% (12 patients) in those assigned for Mitomycin c alone, the difference between groups 12.6%; The progression rate in patients assigned sequential BCG and Mitomycin c about 7 % (3 patients) versus 17 % (7 patients) in those assigned for Mitomycin c alone, the difference between groups 10%. However the side-effects were mainly localized to the bladder, the complications after the treatment more common in patients receive sequential BCG and Mitomycin c than in those receive Mitomycin c alone. Cystitis occur in about 35 patients (83%) in those receiving sequential BCG and Mitomycin c, and two patient 4.7 % developed fever and chills. While in patients receive Mitomycin alone the complications were less cystitis in 4 patients 10%, rash in about 3 patients (7%) and myelosuppression two patients 5%. Conclusion: In this series, sequential BCG and Mitomycin c appears to be more effective than Mitomycin c alone in the treatment of superficial bladder tumors at 36-month follow-up, despite an increased but acceptable local toxicity.This probably because the BCG-induced inflammation might increase the permeability of the bladder mucosa such that Mitomycin c can reach the target tissue more easily and exert its anticancer effect.


Introduction
ladder cancer is the second most common cancer of the genitourinary tract. It accounts for 7% of new cancer cases in men and 2% of new cancer cases in women 1 . Patients typically present with either microscopic or gross hematuria. Bleeding from a bladder tumor is generally intermittent. Therefore resolution, either spontaneously or after antibiotic treatment for presumed bladder infection, does not reduce the need for urologic evaluation 2 . The average age at diagnosis is 65 years. At diagnosis, 60-80% of bladder tumors are non-muscle invasive (NMIBC) and confined to the urothelium and/or lamina propria. These B include papillary tumors, Ta (confined to urothelium) and T1 (lamina propria invasion) or carcinoma in situ (CIS), a flat erythematous lesion. A transurethral resection of the bladder tumor (TURBT) is the standard treatment for Ta and T1 bladder tumors and helps in establishing the diagnosis, staging and assigning a risk profile 3,4 . For low-grade papillary (pTaG1) tumors TURBT may be the only treatment required. However, tumor recurrence is a major problem with higher grade Ta and T1 tumors. At 1 year following TURBT about 20% of patients with low-risk NMIBC and 40% of those with medium-risk NMIBC will develop tumor recurrence. Patients with high-risk NMIBC will express an even higher recurrence rate (90%) at 1-2 years following TURBT. In an effort to reduce the high recurrence rates adjuvant therapy with intravesical agents have been introduced 5,6 . Urinary bladder being an easily accessible organ is well suited for topical therapy. Hence it is not surprising that intravesical therapy has been extensively studied and utilized. The rationale for intravesical therapy is to maximize the exposure of tumors located in the bladder to therapeutic agents while limiting the systemic exposure. Depending on tumor and patient characteristics, a significant number of patients may benefit from intravesical therapy.
Immunomodulatory agents mainly intravesical BCG and chemotherapeutic agents such as Mitomycin C are among the most commonly employed intravesical agents. Perioperative installation of chemotherapy immediately after TURBT is gaining increasing acceptance 5 . The rationale for perioperative instillation includes the destruction of residual microscopic tumor at the site of TURBT and of circulating tumor cells, thereby preventing reimplantation 6,7 . Intravesical therapy can also be given as a maintenance therapy as opposed to an induction course alone to provide long-term immunostimulation or local chemotoxicity aimed at preventing tumor recurrence 7 . Two groups of intravesical therapeutic  agents  are  available.  The  immunotherapeutic agents include Bacillus Calmette-Guérin (BCG) and interferon. The most commonly used chemotherapeutic agents include Mitomycin C, Doxorubicin and more recently Gemcitabine 8 . Bacillus Calmette Guerin: BCG remains the most effective intravesical treatment for NMIBC. Intravesical BCG was introduced as a treatment for urothelial cancer of the bladder more than 30 years ago by Morales et al 10 . Since then several studies and meta-analysis have shown that TURBT followed by intravesical BCG is superior to TURBT alone as well as to TURBT plus intravesical chemotherapy for delaying time to first recurrence 9,10 . Cytotoxic chemotherapy directly kills cancer cells, while immunotherapy generally stimulates the patient's immune response. Increasing the dose of chemotherapy Results in increased cancer cell killing. However, increasing immunotherapy beyond the effective dose will begin to suppress the patient's immune response 11,12 . BCG, or bacillus Calmette-Guerin, is an attenuated form of the bacterium Mycobacterium tuberculosis, used to prevent tuberculosis. It is a potent immune stimulant. The standard dose of BCG is 81 mg for TheraCys® and 50 mg for TICE,® both in 50 cc physiologic saline. Treatment should be postponed for at least 1 to 2 weeks following tumor resection or bladder biopsy. A purified protein derivative (PPD) test may be performed as the response and side effects 13,14 . The precise mechanism of action of BCG is not fully understood. Following the initial mycobacterial adherence to the urothelium, a complex immunological cascade is initiated and leads to a vigorous cellular immune response. Urinary cytokine patterns and the intensity of bladder wall infiltration with immunecompetent cells have been studied to better define the number of doses and the time interval 15 . Zlotta et al, reported in their study that in most patients, the maximal peripheral immune response was already observed after four weekly instillations, although patients who were not previously immunized against mycobacterial antigens required six instillations to achieve maximum stimulation. It has also been shown that the urinary cytokine levels peak at the third week after an induction course 16 . A BCG induction course is typically started only after a minimum of 2 weeks following a TURBT to allow reepithelization and to reduce the risk of systemic side effects. The current view is that the available stains do not differ in efficacy 17 . The dose of intravesical BCG was determined to be 120 mg (Frappier); however, in an effort to reduce the toxicity dose reduction has been proposed. One study reported that a three-fold reduction in dose is as effective as the standard dose with significantly reduced toxicity even in high-risk NMIBC 18 . The standard dwell time for intravesical BCG is 1-2 hours to allow good mycobacterial adhesion. However, the duration can be reduced as an alternative to dose reduction in patients with significant side effects 19 . A standard induction course consists of six weekly instillations. Maintenance is typically given as three weekly instillations at 3 and 6 months and then every 6 months for up to 3 years. At least a year of maintenance is recommended by European Association of Urologists (EAU) and American Urological association (AUA) 20 24,25 . Some of the complications of intravesical BCG therapy are minor and common like dysuria and frequency if sever patient may developed hematuria. Other complications are major but rare like fever, granulomatous prostatitis, granulomatous epididymoorchitis and even BCG sepsis 26 . In summary a recent literature review by Gontero et al, reported that "BCG is the most effective intravesical agent for preventing NMIBC recurrence, but its role in progression remains controversial. In intermediate risk NMIBC, the superiority of BCG over chemotherapy is well established for recurrence but not for progression and needs to be balanced against higher toxicity. With regard to high-risk NMIBC, there is sufficient evidence to show that BCG is the most effective treatment of CIS for ablation, disease-free interval and progression, but the impact of BCG on the natural history of T1G3 tumors relies on a low level of evidence. Maintenance remains crucial for efficacy 27,28 .

Intravesical chemotherapy
In contrast to systemic chemotherapy, where the administered dose is of primary importance, with topical intravesical chemotherapy, response is proportional to drug concentration and duration of exposure. Since duration of exposure is limited by bladder capacity, and increased urine output reduces drug concentration, overnight dehydration is recommended prior to drug instillation. Patients are generally asked to retain the instilled drug for 2 hours. Care must be taken to completely empty the bladder prior to instilling chemotherapy 29,30 . An ultrasound of the bladder after insertion of a catheter is useful in confirming complete emptying, since, surprisingly, catheterization does not reliably empty. It resulted in a protocol that required confirmation of bladder emptying with a bladder scan prior to intravesical mitomycin instillation into the bladder for all patients 31,32 . They recommend that patients lie prone for 15 minutes to displace the air bubble introduced with the catheter, thereby ensuring contact at the bladder dome 33 . The objective of intravesical chemotherapy is to eradicate microscopic residual tumor, prevent tumor recurrence and progression. An ideal intravesical agent should have minimal systemic absorption and maximum efficacy 34 . The absorption and effectiveness of the drug is determined by physiochemical properties of the drug, physiological variables in urine and tissue pharmacokinetics 35 . The absorption and efficacy can be modified by increasing the dose of the drug, decreasing dosing volume, increasing the contact time, decreasing urine production, maximizing bladder emptying and altering the pH 36 . Indications According to AUA, EAU and Société Internationale d'Urologie (SIU) guidelines, intravesical chemotherapy is recommended as single immediate instillation after a TURBT and also as 6-12 weekly prophylactic course for intermediate risk tumors 37,38 . Chemotherapeutic agents Mitomycin C: Mitomycin C is a 334-kD alkylating agent that inhibits DNA synthesis. MMC has an intracellular effect resulting in the production of an alkylating agent. The mode of action is poorly understood. The dose varies between 20 and 80 mg per instillation. It is most commonly given as 40 mg in 40 mL of saline or sterile water administered weekly for 8 weeks followed by monthly instillations for one year. The main side effects are skin rash, irritative bladder symptoms, bladder calcifications, and myelosuppression 39,40 . Contraindications of mitomycin include hypersensitivity, bladder perforation, myelosuppression & thrombocytopenia 41 . In a randomized study, recurrence was nearly cut in half by using an optimized schedule: 40 mg/20 cc (compared with 20 mg/20 cc), overnight dehydration, ultrasound-confirmed complete bladder emptying, alkalinization using 1.3 g of sodium bicarbonate the night before, morning of, and 30 minutes prior to treatment. Mitomycin C is inactivated by acid urine 42 . Recent studies also suggest that local hyperthermia, which can be obtained with a microwave applicator inserted into the bladder with a special catheter, can also enhance the efficacy of mitomycin C, albeit with a significant increase in systemic absorption. Myelosuppression is the primary systemic toxicity of mitomycin 43 . Huland et al, compared 3-year MMC instillation therapy (42 instillations of 20 mg) to no intravesical therapy in a randomized trial after complete TURBT and found a recurrence rate as low as 10.2% when compared with a control group 51%. Recently a study showed that long-term maintenance with MMC was associated with a significant reduction in recurrence rates compared to short-course therapy 52 . Malmstrom 48 .

Patients and methods
The study was designed as a prospective study done in Al-hussain teaching hospital in Thiqar from July 2007 to august 2010. After transurethral resection and multiple biopsies , eighty-three patients suffering from primary superficial (Ta-T1) TCC of the bladder, were randomly assigned to receive intravesical instillations of mitomycin C (MMC) alone for 41 patients, and the sequential BCG and mitomycin, for 42 patients(81 mg BCG infused over 120 min once a week for 2 weeks, followed by 40 mg mitomycin once a week for four weeks. The patients evaluated for complications and recurrence rate they have follow up cystoscope every 3 months for the 1st year then every 6 months for the 2nd year and then yearly average fallow up time was 36 months. The main object of the study were evaluation of recurrence and progression rate and estimate the safety with evaluation of subjective and objective side effects and clinical complications. Mean follow-up time was 36 months TaG2 TaG3 T1G1 T1G2 T1G3  BCG + mitomcine group 3  14  10  8  7  Mitomycin group  4  12  9  8  8  Total  7  26  19  16  15 Single Multiple < 3cm >3cm BCG + Mitomcin group 34  8  16  26  Mitomycin Group  32  9  15  26  Total  66  17  31  52 Patient eligible to either therapy should be evaluated thoroughly. History and physical examination to exclude any hypersensitivity to the instilled drug, recent hematuria or traumatic catheterization. History of BCG sepsis, repeated infection or any sign and symptom of immunosuppression. Investigation specially hematological assessment before every MMC session to exclude myelosuppression. A proper catheterization using 3-way catheter attached to an irrigant fluid, which kept turned off. Emptying of urinary bladder to decrease dilution effect of urine, Mitomycin c also inactivated by the acidic urine. Administer the chemotherapy agent through the main port, clamp with hemostat and attach to drainage bag. The system thus closed. Unclamp the catheter after 120 min. Run 1 liter saline through the irrigant port over next 30-60 min.
Remove and discard the Foley along with drainage bag. For BCG+MMC group 81 mg BCG infused once a week for 2 weeks, followed by 40 mg mitomycin in 40 ml normal saline or distilled water once a week for four weeks. For MMC group Mitomycin c 40mg in 40cc normal saline or distilled water, The procedure repeat weekly fro 6 weeks Patient instructed to have fallow up cystoscope every 3 months for the 1st year, every 6 months for the next year then yearly. Average fallow up 36 months

Results
Of the 83 randomly assigned patients, the analysis demonstrated a highly significant difference in the recurrence rate. Patients assigned sequential BCG and Mitomycin c had lower recurrence rate 16.6 % (7 patients) versus 29.2% (12 patients) in those assigned for Mitomycin c alone, the difference between groups 12.6%; The progression rate in patients assigned sequential BCG and Mitomycin c about 7% (3 patients) versus 17% (7 patients) in those assigned for Mitomycin c alone, the difference between groups 10 %.
Progression rate and recurrence in MMC group Distribution according to recurrence rate in relation to stage and grade. Therap. trial TaG2  TaG3  T1G1  T1G2  T1G3  +ve -ve  +ve  -

80%
Distribution of cases according to progression rate in relation to stage and grade of tumor. According to tumor stage and grade there is significant statistical difference between the number of cases of progression in the two different therapeutic trial (p value < 0.05). We also notice that 68 % of patients with total recurrence and 60% of total progression are from grade 3. Distribution of cases according to recurrence rate in relation to tumor multiplicity.

Discussion
It is well known from the literature that malignant cells are more sensitive to sequential immunotherapy and chemotherapy versus chemotherapy alone. This probably because the BCG-induced inflammation might increase the permeability of the bladder mucosa such that mitomycin c can reach the target tissue more easily and exert its anticancer effect. Superficial bladder tumors, due to their endocavitary location, have represented a model for the administration of local immunotherapy and chemotherapy for a long time. The present study investigated the efficacy and safety of sequential immunotherapy followed by chemotherapy regimen compared to intravesical chemotherapy alone as adjuvant treatment for superficial bladder cancer after a complete transurethral resection. Local side effects, in the form of cystitis symptoms and suprapubic pain, were more severe in patients who underwent sequential BCG with mitomycin c. However, local side effects did not influence the completion of the treatment and were transitory, asymptomatic, and self-recovering shortly after the end of therapy. We thus report a higher incidence of side effects in the combined treatment group, although they were almost uniformly moderate and transient. These results are preliminary and need to be confirmed by larger prospective, multicentric studies. The combined treatment (BCG + MMC) was slightly more expensive than the routine instillation of chemotherapeutic agents alone. There is no consensus on the mitomycin c dose a 20 mg of MMC for 1 hour may be suboptimal. However, a MEDLINE search combining the keywords "MMC" and "bladder instillation" showed a total of 120 articles, 40 of which were particularly relevant and gave sufficient details. Although few articles mention 60 mg of MMC as a possible dose for prophylactic treatment, no results are given for this dose, and a warning is given that higher doses can increase the incidence and severity of side effects 49 .
Looking only at published results, of the 40 studies, 16 studies (40%) used the 20 mg dose, eight studies (20%) used the 30 mg dose, and 16 studies (40%) used the 40 mg dose. According to the manufacture's labeling, the recommended dose is 40 mg for intravesical instillation, and the European Urological Association guidelines recommend 20 to 40 mg as the standard dose of MMC. Therefore, 40 mg is a widely accepted dose, recommended within a range of standard doses by many authorities so in our study, a dosage concentration of MMC 40 mg in 40 mL. Au et al addressed the issue of adequate drug delivery to enhance the prophylactic efficacy of MMC. They compared the efficacy of an optimized 40 mg MMC dose regimen with that of a standard regimen commonly used in their community (20 mg). They introduced different variables, such as minimizing residual urine, reducing urine production during the instillation period, and alkalinizing the urine, so that the significance of the dose factor cannot be singled out, because of the many additional factors 50 . To confirm these clinical findings, we also conducted a clinical trial designed to assess the absorption rate of MMC following BCG instillation because the inflammatory reaction enhanced by BCG instillation probably increase the absorption of mitomycin c. According to this study, a dosage concentration of MMC 40 mg in 40 mL remained strongly below the accepted threshold for MMCinduced side effects. We note that series displaying a lower recurrence rate usually have a different selection of patients, including those with good-risk cases, whereas in our study, we try to divide the patients equally between the two therapeutic trial with respect to tumor grade, stage, multiplicity and size of the tumor.

In conclusion
In our series, sequential BCG and mitomycin c appears to be more effective than mitomycin c alone in the treatment for superficial bladder tumors at 36-month follow-up, despite an increased but acceptable local toxicity. This probably because the BCG-induced inflammation might increase the permeability of the bladder mucosa such that mitomycin c can reach the target tissue more easily and exert its anticancer.