**Core Concept**
Laparoscopic cholecystectomy for cholelithiasis can occasionally lead to unexpected findings, such as gallbladder cancer. In this scenario, the patient has adenocarcinoma with muscle layer invasion, indicating a more advanced tumor. The management of gallbladder cancer depends on the stage and extent of the disease.

**Why the Correct Answer is Right**
The correct answer is B, wedge hepatic resection with lymph node dissection. This is because the tumor has invaded the muscle layer, indicating T2b or T3 disease according to the TNM staging system. For these stages, surgical resection is the primary treatment, and it involves removal of the gallbladder bed (wedge hepatic resection) and regional lymph nodes to assess for metastasis. This approach aims to achieve a R0 resection, which is crucial for improved survival in gallbladder cancer.

**Why Each Wrong Option is Incorrect**

**Option A:** Waiting and regular follow-up are not appropriate for gallbladder cancer with muscle layer invasion, as the tumor has already reached an advanced stage, and delay in treatment can lead to worse outcomes.

**Option C:** Excising all port sites is not a standard procedure for gallbladder cancer management. While port site metastases can occur, they are rare, and routine excision of port sites is not recommended.

**Option D:** Radiotherapy may be used as an adjuvant treatment in gallbladder cancer, but it is not the primary treatment for a T2b or T3 tumor. Surgery remains the mainstay of treatment for these stages.

**Clinical Pearl / High-Yield Fact**
For patients undergoing laparoscopic cholecystectomy, a frozen section biopsy should be performed if there is any suspicion of gallbladder cancer. This can help identify patients who require further surgical resection and adjuvant therapy.

**✓ Correct Answer: B. Wedge hepatic resection with lymph node dissection**