Dabrafenib, Trametinib, and Spartalizumab for the Treatment of BRAF V600E or V600K Mutation Positive Stage IIIB/C/D Melanoma

Inclusion Criteria:

* Capable of giving written informed consent, which includes compliance with the requirements and restrictions listed in the consent form
* Patients must have histologically or cytologically confirmed clinically detected, node involved Stage IIIB/C/D melanoma by American Joint Committee on Cancer (AJCC) version 8 and surgically resectable disease. The definition of resectability can be determined by the patient's surgical oncologist and verified via discussion at multidisciplinary tumor conference attended by melanoma medical and surgical oncology staff. Resectable tumors are defined as having no significant vascular, neural or bony involvement that would preclude complete resection or necessitate the use of adjuvant radiation. Only cases where a complete surgical resection with tumor- free margins can safely be achieved are defined as resectable
* BRAF mutation-positive melanoma (V600E or V600K) based on report from a Clinical Laboratory Improvement Act (CLIA) certified laboratory
* Patients must have measurable disease, defined by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1
* Patients who have been previously treated in the adjuvant setting with ipilimumab or interferon alpha or investigational vaccines for melanoma will be eligible for treatment after a 28 day wash-out period
* Patients who have previously received anti PD-1 in the adjuvant setting will be allowed if it has been six months or longer since previous drug exposure
* Eastern Cooperative Oncology Group (ECOG) performance status 0-1
* Women of childbearing potential, defined as all women physiologically capable of becoming pregnant will be required to use highly effective methods of contraception during dosing and for 150-days after stopping treatment with spartalizumab. Highly effective contraception methods include:

  * Total abstinence (when this is in line with the preferred and usual lifestyle of the subject). Periodic abstinence (e.g., calendar, ovulation, symptothermal, post-ovulation methods) and withdrawal are not acceptable methods of contraception.
  * Female sterilization (have had surgical bilateral oophorectomy with or without hysterectomy), total hysterectomy, or tubal ligation at least six weeks before taking study treatment. In case of oophorectomy alone, only when the reproductive status of the woman has been confirmed by follow up hormone level assessment.
  * Male sterilization (at least 6 months prior to screening). The vasectomized male partner should be the sole partner for that subject
  * Placement of a non-hormonal intrauterine device (IUD) or intrauterine system (IUS) with a documented failure rate of less than 1% per year
  * Notes:

    * Double-barrier contraception: condom and occlusive cap (diaphragm or cervical/vault caps) with a vaginal spermicidal agent (foam/gel/cream/suppository) are not considered highly effective methods of contraception.
    * Hormonal-based methods (e.g., oral contraceptives) are not considered as highly effective methods of contraception due to potential drug-drug interactions with dabrafenib.
* Women are considered post-menopausal and not of child bearing potential if they have had 12 months of natural (spontaneous) amenorrhea with an appropriate clinical profile (i.e. age appropriate, history of vasomotor symptoms) or have had surgical bilateral oophorectomy (with or without hysterectomy), total hysterectomy, or tubal ligation at least six weeks ago. In the case of oophorectomy alone, only when the reproductive status of the woman has been confirmed by follow up hormone level assessment is she considered not of childbearing potential
* Sexually active males must use a condom during intercourse while on treatment and for 150 days after stopping treatment with spartalizumab and should not father a child in this period. A condom is required to be used by vasectomized men as well during intercourse in order to prevent delivery of the drug via semen
* Absolute neutrophil count (ANC) \>= 1500/uL
* Platelets \>= 100,000/uL
* Hemoglobin \>= 9.0 g/dL or \>= 5.6 mmol/L

  * Criteria must be met without erythropoietin dependency and without packed red blood cell (pRBC) transfusion within last 2 weeks
* Creatinine =\< 1.5 x upper limit of normal (ULN) OR measured or calculated creatinine clearance (glomerular filtration rate \[GFR\] can also be used in place of creatinine or creatinine clearance \[CrCl\]) \>= 30 mL/min for participant with creatinine levels \> 1.5 x institutional ULN

  * Creatinine clearance (CrCl) should be calculated per institutional standard
* Total bilirubin =\< 1.5 x ULN OR direct bilirubin =\< ULN for participants with total bilirubin levels \> 1.5 x ULN
* Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase \[SGOT\]) and alanine aminotransferase (ALT) (serum glutamic pyruvic transaminase \[SGPT\]) =\< 2.5 x ULN
* International normalized ratio (INR) OR prothrombin time (PT) =\<1.5 x ULN unless participant is receiving anticoagulant therapy as long as prothrombin time (PT) or partial thromboplastin time (aPTT) is within therapeutic range of intended use of anticoagulants
* Activated partial thromboplastin time (aPTT) =\< 1.5 x ULN unless participant is receiving anticoagulant therapy as long as PT or aPTT is within therapeutic range of intended use of anticoagulants

Exclusion Criteria:

* Currently receiving cancer therapy (chemotherapy, radiation therapy, immunotherapy, or biologic therapy) or investigational anti-cancer drug within 28 days
* Evidence of metastatic melanoma or patients with only in-transit metastases without involved nodes
* Prior BRAF or MEK inhibitor use
* Prior anti PD-1 or anti PD-L1 inhibitor use in last 6 months
* Prior malignancy active within the previous 2 years except for patient's prior diagnosis of melanoma and locally curable cancers that have been apparently cured, such as basal or squamous cell skin cancer, superficial bladder cancer, or carcinoma in situ of the prostate, cervix, or breast with local control measures (surgery, radiation)
* Subjects with active, known or suspected autoimmune disease. Subjects with vitiligo, type I diabetes mellitus, residual hypothyroidism due to autoimmune condition only requiring hormone replacement, psoriasis not requiring systemic treatment, or conditions not expected to recur in the absence of an external trigger are permitted to enroll
* Subjects with a condition requiring systemic treatment with either corticosteroids (\> 10 mg daily prednisone equivalents) or other immunosuppressive medications within 14 days of study drug administration. Inhaled or topical steroids and adrenal replacement doses \> 10 mg daily prednisone equivalents are permitted in the absence of active autoimmune disease
* Any positive test result for hepatitis B or C and human immunodeficiency virus (HIV) virus indicating acute or chronic infection
* Known history of testing positive for human immunodeficiency virus or known acquired immunodeficiency syndrome
* History of severe hypersensitivity reaction to any monoclonal antibody
* History of Central serous retinopathy (CSR) or retinal vein occlusion (RVO), or predisposing factors to RVO or CSR (e.g. uncontrolled glaucoma or ocular hypertension, uncontrolled systemic disease such as hypertension, diabetes mellitus, or history of hyperviscosity or hypercoagulability syndromes)
* Presence of active gastrointestinal disease or other condition that will interfere significantly with the absorption, distribution, metabolism, or excretion of drugs
* Corrected QT (QTc) interval \>= 480 msec (\>= 500 msec for subjects with bundle branch block)
* Uncontrolled arrhythmias
* Class II, III, or IV heart failure as defined by the New York Heart Association (NYHA) functional classification system
* Pregnant or lactating female
* Unwillingness or inability to follow the procedures required in the protocol
* Uncontrolled diabetes, hypertension or other medical conditions that may interfere with assessment of toxicity
* Subjects with known glucose 6 phosphate dehydrogenase (G6PD) deficiency